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Balla H, Borsodi K, Őrsy P, Horváth B, Molnár PJ, Lénárt Á, Kosztelnik M, Ruisanchez É, Wess J, Offermanns S, Nyirády P, Benyó Z. Intracellular signaling pathways of muscarinic acetylcholine receptor-mediated detrusor muscle contractions. Am J Physiol Renal Physiol 2023; 325:F618-F628. [PMID: 37675459 DOI: 10.1152/ajprenal.00261.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 08/10/2023] [Accepted: 08/27/2023] [Indexed: 09/08/2023] Open
Abstract
Acetylcholine plays an essential role in the regulation of detrusor muscle contractions, and antimuscarinics are widely used in the management of overactive bladder syndrome. However, several adverse effects limit their application and patients' compliance. Thus, this study aimed to further analyze the signal transduction of M2 and M3 receptors in the murine urinary bladder to eventually find more specific therapeutic targets. Experiments were performed on adult male wild-type, M2, M3, M2/M3, or Gαq/11 knockout (KO), and pertussis toxin (PTX)-treated mice. Contraction force and RhoA activity were measured in the urinary bladder smooth muscle (UBSM). Our results indicate that carbamoylcholine (CCh)-induced contractions were associated with increased activity of RhoA and were reduced in the presence of the Rho-associated kinase (ROCK) inhibitor Y-27632 in UBSM. CCh-evoked contractile responses and RhoA activation were markedly reduced in detrusor strips lacking either M2 or M3 receptors and abolished in M2/M3 KO mice. Inhibition of Gαi-coupled signaling by PTX treatment shifted the concentration-response curve of CCh to the right and diminished RhoA activation. CCh-induced contractile responses were markedly decreased in Gαq/11 KO mice; however, RhoA activation was unaffected. In conclusion, cholinergic detrusor contraction and RhoA activation are mediated by both M2 and M3 receptors. Furthermore, whereas both Gαi and Gαq/11 proteins mediate UBSM contraction, the activation at the RhoA-ROCK pathway appears to be linked specifically to Gαi. These findings may aid the identification of more specific therapeutic targets for bladder dysfunctions.NEW & NOTEWORTHY Muscarinic acetylcholine receptors are of utmost importance in physiological regulation of micturition and also in the development of voiding disorders. We demonstrate that the RhoA-Rho-associated kinase (ROCK) pathway plays a crucial role in contractions induced by cholinergic stimulation in detrusor muscle. Activation of RhoA is mediated by both M2 and M3 receptors as well as by Gi but not Gq/11 proteins. The Gi-RhoA-ROCK pathway may provide a novel therapeutic target for overactive voiding disorders.
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Affiliation(s)
- Helga Balla
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Kinga Borsodi
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Petra Őrsy
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Béla Horváth
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Péter József Molnár
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
- Department of Urology, Semmelweis University, Budapest, Hungary
| | - Ádám Lénárt
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Mónika Kosztelnik
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
- HUN-REN-SE Cerebrosvascular and Neurodegenerative Disease Research Group, Budapest, Hungary
| | - Éva Ruisanchez
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
- HUN-REN-SE Cerebrosvascular and Neurodegenerative Disease Research Group, Budapest, Hungary
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, United States
| | - Stefan Offermanns
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Péter Nyirády
- Department of Urology, Semmelweis University, Budapest, Hungary
| | - Zoltán Benyó
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
- HUN-REN-SE Cerebrosvascular and Neurodegenerative Disease Research Group, Budapest, Hungary
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Aroniadou-Anderjaska V, Figueiredo TH, de Araujo Furtado M, Pidoplichko VI, Braga MFM. Mechanisms of Organophosphate Toxicity and the Role of Acetylcholinesterase Inhibition. TOXICS 2023; 11:866. [PMID: 37888716 PMCID: PMC10611379 DOI: 10.3390/toxics11100866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/11/2023] [Accepted: 10/17/2023] [Indexed: 10/28/2023]
Abstract
Organophosphorus compounds (OPs) have applications in agriculture (e.g., pesticides), industry (e.g., flame retardants), and chemical warfare (nerve agents). In high doses or chronic exposure, they can be toxic or lethal. The primary mechanism, common among all OPs, that initiates their toxic effects is the inhibition of acetylcholinesterase. In acute OP exposure, the subsequent surge of acetylcholine in cholinergic synapses causes a peripheral cholinergic crisis and status epilepticus (SE), either of which can lead to death. If death is averted without effective seizure control, long-term brain damage ensues. This review describes the mechanisms by which elevated acetylcholine can cause respiratory failure and trigger SE; the role of the amygdala in seizure initiation; the role of M1 muscarinic receptors in the early stages of SE; the neurotoxic pathways activated by SE (excitotoxicity/Ca++ overload/oxidative stress, neuroinflammation); and neurotoxic mechanisms linked to low-dose, chronic exposure (Ca++ dyshomeostasis/oxidative stress, inflammation), which do not depend on SE and do not necessarily involve acetylcholinesterase inhibition. The evidence so far indicates that brain damage from acute OP exposure is a direct result of SE, while the neurotoxic mechanisms activated by low-dose chronic exposure are independent of SE and may not be associated with acetylcholinesterase inhibition.
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Affiliation(s)
- Vassiliki Aroniadou-Anderjaska
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (V.A.-A.); (V.I.P.)
- Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Taiza H. Figueiredo
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (V.A.-A.); (V.I.P.)
| | - Marcio de Araujo Furtado
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (V.A.-A.); (V.I.P.)
| | - Volodymyr I. Pidoplichko
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (V.A.-A.); (V.I.P.)
| | - Maria F. M. Braga
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (V.A.-A.); (V.I.P.)
- Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
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Hagio H, Koyama W, Hosaka S, Song AD, Narantsatsral J, Matsuda K, Sugihara T, Shimizu T, Koyanagi M, Terakita A, Hibi M. Optogenetic manipulation of Gq- and Gi/o-coupled receptor signaling in neurons and heart muscle cells. eLife 2023; 12:e83974. [PMID: 37589544 PMCID: PMC10435233 DOI: 10.7554/elife.83974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 07/27/2023] [Indexed: 08/18/2023] Open
Abstract
G-protein-coupled receptors (GPCRs) transmit signals into cells depending on the G protein type. To analyze the functions of GPCR signaling, we assessed the effectiveness of animal G-protein-coupled bistable rhodopsins that can be controlled into active and inactive states by light application using zebrafish. We expressed Gq- and Gi/o-coupled bistable rhodopsins in hindbrain reticulospinal V2a neurons, which are involved in locomotion, or in cardiomyocytes. Light stimulation of the reticulospinal V2a neurons expressing Gq-coupled spider Rh1 resulted in an increase in the intracellular Ca2+ level and evoked swimming behavior. Light stimulation of cardiomyocytes expressing the Gi/o-coupled mosquito Opn3, pufferfish TMT opsin, or lamprey parapinopsin induced cardiac arrest, and the effect was suppressed by treatment with pertussis toxin or barium, suggesting that Gi/o-dependent regulation of inward-rectifier K+ channels controls cardiac function. These data indicate that these rhodopsins are useful for optogenetic control of GPCR-mediated signaling in zebrafish neurons and cardiomyocytes.
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Affiliation(s)
- Hanako Hagio
- Graduate School of Science, Nagoya UniversityNagoyaJapan
- Graduate School of Bioagricultural Sciences, Nagoya UniversityNagoyaJapan
- Institute for Advanced Research, Nagoya UniversityNagoyaJapan
| | - Wataru Koyama
- Graduate School of Science, Nagoya UniversityNagoyaJapan
| | - Shiori Hosaka
- Graduate School of Science, Nagoya UniversityNagoyaJapan
| | | | | | - Koji Matsuda
- Graduate School of Science, Nagoya UniversityNagoyaJapan
| | | | | | | | - Akihisa Terakita
- Graduate School of Science, Osaka Metropolitan UniversityOsakaJapan
| | - Masahiko Hibi
- Graduate School of Science, Nagoya UniversityNagoyaJapan
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Zheng F, Wess J, Alzheimer C. Long-Term-But Not Short-Term-Plasticity at the Mossy Fiber-CA3 Pyramidal Cell Synapse in Hippocampus Is Altered in M1/M3 Muscarinic Acetylcholine Receptor Double Knockout Mice. Cells 2023; 12:1890. [PMID: 37508553 PMCID: PMC10378318 DOI: 10.3390/cells12141890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/13/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023] Open
Abstract
Muscarinic acetylcholine receptors are well-known for their crucial involvement in hippocampus-dependent learning and memory, but the exact roles of the various receptor subtypes (M1-M5) are still not fully understood. Here, we studied how M1 and M3 receptors affect plasticity at the mossy fiber (MF)-CA3 pyramidal cell synapse. In hippocampal slices from M1/M3 receptor double knockout (M1/M3-dKO) mice, the signature short-term plasticity of the MF-CA3 synapse was not significantly affected. However, the rather unique NMDA receptor-independent and presynaptic form of long-term potentiation (LTP) of this synapse was much larger in M1/M3-deficient slices compared to wild-type slices in both field potential and whole-cell recordings. Consistent with its presynaptic origin, induction of MF-LTP strongly enhanced the excitatory drive onto single CA3 pyramidal cells, with the effect being more pronounced in M1/M3-dKO cells. In an earlier study, we found that the deletion of M2 receptors in mice disinhibits MF-LTP in a similar fashion, suggesting that endogenous acetylcholine employs both M1/M3 and M2 receptors to constrain MF-LTP. Importantly, such synergism was not observed for MF long-term depression (LTD). Low-frequency stimulation, which reliably induced LTD of MF synapses in control slices, failed to do so in M1/M3-dKO slices and gave rise to LTP instead. In striking contrast, loss of M2 receptors augmented LTD when compared to control slices. Taken together, our data demonstrate convergence of M1/M3 and M2 receptors on MF-LTP, but functional divergence on MF-LTD, with the net effect resulting in a well-balanced bidirectional plasticity of the MF-CA3 pyramidal cell synapse.
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Affiliation(s)
- Fang Zheng
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Biological Chemistry, NIDDK, NIH, Bethesda, MD 20892, USA
| | - Christian Alzheimer
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
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5
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Sugisaki E, Fukushima Y, Nakajima N, Aihara T. The dependence of acetylcholine on dynamic changes in the membrane potential and an action potential during spike timing-dependent plasticity induction in the hippocampus. Eur J Neurosci 2022; 56:5972-5986. [PMID: 36164804 DOI: 10.1111/ejn.15832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 09/01/2022] [Accepted: 09/16/2022] [Indexed: 12/29/2022]
Abstract
The hippocampus is an important area for memory encoding and retrieval and is the location of spike timing-dependent plasticity (STDP), a basic phenomenon of learning and memory. STDP is facilitated if acetylcholine (ACh) is released from cholinergic neurons during attentional processes. However, it is unclear how ACh influences postsynaptic changes during STDP induction and determines the STDP magnitude. To address these issues, we obtained patch clamp recordings from CA1 pyramidal neurons to evaluate the postsynaptic changes during stimuli injection in Schaffer collaterals by quantifying baseline amplitudes (i.e., the lowest values elicited by paired pulses comprising STDP stimuli) and action potentials. The results showed that baseline amplitudes were elevated if eserine was applied in the presence of picrotoxin. In addition, muscarinic ACh receptors (mAChRs) contributed more to the baseline amplitude elevation than nicotinic AChRs (nAChRs). Moreover, the magnitude of the STDP depended on the magnitude of the baseline amplitude. However, in the absence of picrotoxin, baseline amplitudes were balanced, regardless of the ACh concentration, resulting in a similar magnitude of the STDP, except under the nAChR alone-activated condition, which showed a larger STDP and lower baseline amplitude induction. This was due to broadened widths of action potentials. These results suggest that activation of mAChRs and nAChRs, which are effective for baseline amplitudes and action potentials, respectively, plays an important role in postsynaptic changes during memory consolidation.
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Affiliation(s)
- Eriko Sugisaki
- Brain Science Institute, Tamagawa University, Tokyo, Japan
| | - Yasuhiro Fukushima
- Brain Science Institute, Tamagawa University, Tokyo, Japan.,Kawasaki University of Medical Welfare, Okayama, Japan
| | - Naoki Nakajima
- Graduated School of Engineering, Tamagawa University, Tokyo, Japan
| | - Takeshi Aihara
- Brain Science Institute, Tamagawa University, Tokyo, Japan
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6
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Slater C, Liu Y, Weiss E, Yu K, Wang Q. The Neuromodulatory Role of the Noradrenergic and Cholinergic Systems and Their Interplay in Cognitive Functions: A Focused Review. Brain Sci 2022; 12:890. [PMID: 35884697 PMCID: PMC9320657 DOI: 10.3390/brainsci12070890] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 06/28/2022] [Accepted: 06/30/2022] [Indexed: 12/15/2022] Open
Abstract
The noradrenergic and cholinergic modulation of functionally distinct regions of the brain has become one of the primary organizational principles behind understanding the contribution of each system to the diversity of neural computation in the central nervous system. Decades of work has shown that a diverse family of receptors, stratified across different brain regions, and circuit-specific afferent and efferent projections play a critical role in helping such widespread neuromodulatory systems obtain substantial heterogeneity in neural information processing. This review briefly discusses the anatomical layout of both the noradrenergic and cholinergic systems, as well as the types and distributions of relevant receptors for each system. Previous work characterizing the direct and indirect interaction between these two systems is discussed, especially in the context of higher order cognitive functions such as attention, learning, and the decision-making process. Though a substantial amount of work has been done to characterize the role of each neuromodulator, a cohesive understanding of the region-specific cooperation of these two systems is not yet fully realized. For the field to progress, new experiments will need to be conducted that capitalize on the modular subdivisions of the brain and systematically explore the role of norepinephrine and acetylcholine in each of these subunits and across the full range of receptors expressed in different cell types in these regions.
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Affiliation(s)
- Cody Slater
- Department of Biomedical Engineering, Columbia University, ET 351, 500 W. 120th Street, New York, NY 10027, USA; (C.S.); (Y.L.); (E.W.); (K.Y.)
- Vagelos College of Physicians and Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, USA
| | - Yuxiang Liu
- Department of Biomedical Engineering, Columbia University, ET 351, 500 W. 120th Street, New York, NY 10027, USA; (C.S.); (Y.L.); (E.W.); (K.Y.)
| | - Evan Weiss
- Department of Biomedical Engineering, Columbia University, ET 351, 500 W. 120th Street, New York, NY 10027, USA; (C.S.); (Y.L.); (E.W.); (K.Y.)
| | - Kunpeng Yu
- Department of Biomedical Engineering, Columbia University, ET 351, 500 W. 120th Street, New York, NY 10027, USA; (C.S.); (Y.L.); (E.W.); (K.Y.)
| | - Qi Wang
- Department of Biomedical Engineering, Columbia University, ET 351, 500 W. 120th Street, New York, NY 10027, USA; (C.S.); (Y.L.); (E.W.); (K.Y.)
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Fuchsberger T, Paulsen O. Modulation of hippocampal plasticity in learning and memory. Curr Opin Neurobiol 2022; 75:102558. [PMID: 35660989 DOI: 10.1016/j.conb.2022.102558] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/15/2022] [Accepted: 04/25/2022] [Indexed: 11/17/2022]
Abstract
Synaptic plasticity plays a central role in the study of neural mechanisms of learning and memory. Plasticity rules are not invariant over time but are under neuromodulatory control, enabling behavioral states to influence memory formation. Neuromodulation controls synaptic plasticity at network level by directing information flow, at circuit level through changes in excitation/inhibition balance, and at synaptic level through modulation of intracellular signaling cascades. Although most research has focused on modulation of principal neurons, recent progress has uncovered important roles for interneurons in not only routing information, but also setting conditions for synaptic plasticity. Moreover, astrocytes have been shown to both gate and mediate plasticity. These additional mechanisms must be considered for a comprehensive mechanistic understanding of learning and memory.
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Affiliation(s)
- Tanja Fuchsberger
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Ole Paulsen
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK.
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Mackenzie-Gray Scott CA, Pelkey KA, Caccavano AP, Abebe D, Lai M, Black KN, Brown ND, Trevelyan AJ, McBain CJ. Resilient Hippocampal Gamma Rhythmogenesis and Parvalbumin-Expressing Interneuron Function Before and After Plaque Burden in 5xFAD Alzheimer's Disease Model. Front Synaptic Neurosci 2022; 14:857608. [PMID: 35645763 PMCID: PMC9131009 DOI: 10.3389/fnsyn.2022.857608] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 04/14/2022] [Indexed: 12/04/2022] Open
Abstract
Recent studies have implicated impaired Parvalbumin Fast-Spiking Interneuron (PVIN) function as a precipitating factor underlying abnormalities in network synchrony, oscillatory rhythms, and cognition associated with Alzheimer's disease (AD). However, a complete developmental investigation of potential gamma deficits, induced by commonly used carbachol or kainate in ex vivo slice preparations, within AD model mice is lacking. We examined gamma oscillations using field recordings in acute hippocampal slices from 5xFAD and control mice, through the period of developing pathology, starting at 3 months of age, when there is minimal plaque presence in the hippocampus, through to 12+ months of age, when plaque burden is high. In addition, we examined PVIN participation in gamma rhythms using targeted cell-attached recordings of genetically-reported PVINs, in both wild type and mutant mice. In parallel, a developmental immunohistochemical characterisation probing the PVIN-associated expression of PV and perineuronal nets (PNNs) was compared between control and 5xFAD mice. Remarkably, this comprehensive longitudinal evaluation failed to reveal any obvious correlations between PVIN deficits (electrical and molecular), circuit rhythmogenesis (gamma frequency and power), and Aβ deposits/plaque formation. By 6-12 months, 5xFAD animals have extensive plaque formation throughout the hippocampus. However, a deficit in gamma oscillatory power was only evident in the oldest 5xFAD animals (12+ months), and only when using kainate, and not carbachol, to induce the oscillations. We found no difference in PV firing or phase preference during kainate-induced oscillations in younger or older 5xFAD mice compared to control, and a reduction of PV and PNNs only in the oldest 5xFAD mice. The lack of a clear relationship between PVIN function, network rhythmicity, and plaque formation in our study highlights an unexpected resilience in PVIN function in the face of extensive plaque pathology associated with this model, calling into question the presumptive link between PVIN pathology and Alzheimer's progression.
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Affiliation(s)
- Connie A. Mackenzie-Gray Scott
- Section on Cellular and Synaptic Physiology, NICHD - Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, MD, United States
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Kenneth A. Pelkey
- Section on Cellular and Synaptic Physiology, NICHD - Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Adam P. Caccavano
- Section on Cellular and Synaptic Physiology, NICHD - Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Daniel Abebe
- Section on Cellular and Synaptic Physiology, NICHD - Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Mandy Lai
- Section on Cellular and Synaptic Physiology, NICHD - Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Khayla N. Black
- Section on Cellular and Synaptic Physiology, NICHD - Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Nicolette D. Brown
- Section on Cellular and Synaptic Physiology, NICHD - Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Andrew J. Trevelyan
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Chris J. McBain
- Section on Cellular and Synaptic Physiology, NICHD - Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, MD, United States
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Wang Y, Jin YK, Guo TC, Li ZR, Feng BY, Han JH, Vreugdenhil M, Lu CB. Activation of Dopamine 4 Receptor Subtype Enhances Gamma Oscillations in Hippocampal Slices of Aged Mice. Front Aging Neurosci 2022; 14:838803. [PMID: 35370600 PMCID: PMC8966726 DOI: 10.3389/fnagi.2022.838803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 02/17/2022] [Indexed: 11/26/2022] Open
Abstract
Aim Neural network oscillation at gamma frequency band (γ oscillation, 30–80 Hz) is synchronized synaptic potentials important for higher brain processes and altered in normal aging. Recent studies indicate that activation of dopamine 4 receptor (DR4) enhanced hippocampal γ oscillation of young mice and fully recovered the impaired hippocampal synaptic plasticity of aged mice, we determined whether this receptor is involved in aging-related modulation of hippocampal γ oscillation. Methods We recorded γ oscillations in the hippocampal CA3 region from young and aged C57bl6 mice and investigated the effects of dopamine and the selective dopamine receptor (DR) agonists on γ oscillation. Results We first found that γ oscillation power (γ power) was reduced in aged mice compared to young mice, which was restored by exogenous application of dopamine (DA). Second, the selective agonists for different D1- and D2-type dopamine receptors increased γ power in young mice but had little or small effect in aged mice. Third, the D4 receptor (D4R) agonist PD168077 caused a large increase of γ power in aged mice but a small increase in young mice, and its effect is blocked by the highly specific D4R antagonist L-745,870 or largely reduced by a NMDAR antagonist. Fourth, D3R agonist had no effect on γ power of either young or aged mice. Conclusion This study reveals DR subtype-mediated hippocampal γ oscillations is aging-related and DR4 activation restores the impaired γ oscillations in aged brain, and suggests that D4R is the potential target for the improvement of cognitive deficits related to the aging and aging-related diseases.
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Affiliation(s)
- Yuan Wang
- Henan International Key Laboratory for Non-invasive Neuromodulation, Department of Physiology and Pathology, Xinxiang Medical University, Xinxiang, China
| | - Yi-Kai Jin
- Henan International Key Laboratory for Non-invasive Neuromodulation, Department of Physiology and Pathology, Xinxiang Medical University, Xinxiang, China
| | - Tie-Cheng Guo
- Department of Rehabilitation Medicine, Tongji Medical College, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Zhen-Rong Li
- Henan International Key Laboratory for Non-invasive Neuromodulation, Department of Physiology and Pathology, Xinxiang Medical University, Xinxiang, China
- School of Public Health, Xinxiang Medical University, Xinxiang, China
| | - Bing-Yan Feng
- Henan International Key Laboratory for Non-invasive Neuromodulation, Department of Physiology and Pathology, Xinxiang Medical University, Xinxiang, China
| | - Jin-Hong Han
- Henan International Key Laboratory for Non-invasive Neuromodulation, Department of Physiology and Pathology, Xinxiang Medical University, Xinxiang, China
| | - Martin Vreugdenhil
- Department of Health Sciences, Birmingham City University, Birmingham, United Kingdom
- *Correspondence: Martin Vreugdenhil,
| | - Cheng-Biao Lu
- Henan International Key Laboratory for Non-invasive Neuromodulation, Department of Physiology and Pathology, Xinxiang Medical University, Xinxiang, China
- Cheng-Biao Lu,
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Klemz A, Wildner F, Tütüncü E, Gerevich Z. Regulation of Hippocampal Gamma Oscillations by Modulation of Intrinsic Neuronal Excitability. Front Neural Circuits 2022; 15:778022. [PMID: 35177966 PMCID: PMC8845518 DOI: 10.3389/fncir.2021.778022] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 12/21/2021] [Indexed: 11/16/2022] Open
Abstract
Ion channels activated around the subthreshold membrane potential determine the likelihood of neuronal firing in response to synaptic inputs, a process described as intrinsic neuronal excitability. Long-term plasticity of chemical synaptic transmission is traditionally considered the main cellular mechanism of information storage in the brain; however, voltage- and calcium-activated channels modulating the inputs or outputs of neurons are also subjects of plastic changes and play a major role in learning and memory formation. Gamma oscillations are associated with numerous higher cognitive functions such as learning and memory, but our knowledge of their dependence on intrinsic plasticity is by far limited. Here we investigated the roles of potassium and calcium channels activated at near subthreshold membrane potentials in cholinergically induced persistent gamma oscillations measured in the CA3 area of rat hippocampal slices. Among potassium channels, which are responsible for the afterhyperpolarization in CA3 pyramidal cells, we found that blockers of SK (KCa2) and KV7.2/7.3 (KCNQ2/3), but not the BK (KCa1.1) and IK (KCa3.1) channels, increased the power of gamma oscillations. On the contrary, activators of these channels had an attenuating effect without affecting the frequency. Pharmacological blockade of the low voltage-activated T-type calcium channels (CaV3.1–3.3) reduced gamma power and increased the oscillation peak frequency. Enhancement of these channels also inhibited the peak power without altering the frequency of the oscillations. The presented data suggest that voltage- and calcium-activated ion channels involved in intrinsic excitability strongly regulate the power of hippocampal gamma oscillations. Targeting these channels could represent a valuable pharmacological strategy against cognitive impairment.
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11
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Palacios-Filardo J, Udakis M, Brown GA, Tehan BG, Congreve MS, Nathan PJ, Brown AJH, Mellor JR. Acetylcholine prioritises direct synaptic inputs from entorhinal cortex to CA1 by differential modulation of feedforward inhibitory circuits. Nat Commun 2021; 12:5475. [PMID: 34531380 PMCID: PMC8445995 DOI: 10.1038/s41467-021-25280-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 07/21/2021] [Indexed: 02/08/2023] Open
Abstract
Acetylcholine release in the hippocampus plays a central role in the formation of new memory representations. An influential but largely untested theory proposes that memory formation requires acetylcholine to enhance responses in CA1 to new sensory information from entorhinal cortex whilst depressing inputs from previously encoded representations in CA3. Here, we show that excitatory inputs from entorhinal cortex and CA3 are depressed equally by synaptic release of acetylcholine in CA1. However, feedforward inhibition from entorhinal cortex exhibits greater depression than CA3 resulting in a selective enhancement of excitatory-inhibitory balance and CA1 activation by entorhinal inputs. Entorhinal and CA3 pathways engage different feedforward interneuron subpopulations and cholinergic modulation of presynaptic function is mediated differentially by muscarinic M3 and M4 receptors, respectively. Thus, our data support a role and mechanisms for acetylcholine to prioritise novel information inputs to CA1 during memory formation.
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Affiliation(s)
- Jon Palacios-Filardo
- Center for Synaptic Plasticity, School of Physiology, Pharmacology and Neuroscience, University of Bristol, University Walk, Bristol, UK
| | - Matt Udakis
- Center for Synaptic Plasticity, School of Physiology, Pharmacology and Neuroscience, University of Bristol, University Walk, Bristol, UK
| | - Giles A Brown
- Sosei Heptares, Steinmetz Building, Granta Park, Great Abingdon, Cambridge, UK
- OMass Therapeutics Ltd, The Schrödinger Building, Oxford, UK
| | - Benjamin G Tehan
- Sosei Heptares, Steinmetz Building, Granta Park, Great Abingdon, Cambridge, UK
- OMass Therapeutics Ltd, The Schrödinger Building, Oxford, UK
| | - Miles S Congreve
- Sosei Heptares, Steinmetz Building, Granta Park, Great Abingdon, Cambridge, UK
| | - Pradeep J Nathan
- Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - Alastair J H Brown
- Sosei Heptares, Steinmetz Building, Granta Park, Great Abingdon, Cambridge, UK
| | - Jack R Mellor
- Center for Synaptic Plasticity, School of Physiology, Pharmacology and Neuroscience, University of Bristol, University Walk, Bristol, UK.
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12
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Headley DB, Kyriazi P, Feng F, Nair SS, Pare D. Gamma Oscillations in the Basolateral Amygdala: Localization, Microcircuitry, and Behavioral Correlates. J Neurosci 2021; 41:6087-6101. [PMID: 34088799 PMCID: PMC8276735 DOI: 10.1523/jneurosci.3159-20.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 04/04/2021] [Accepted: 04/06/2021] [Indexed: 11/21/2022] Open
Abstract
The lateral (LA) and basolateral (BL) nuclei of the amygdala regulate emotional behaviors. Despite their dissimilar extrinsic connectivity, they are often combined, perhaps because their cellular composition is similar to that of the cerebral cortex, including excitatory principal cells reciprocally connected with fast-spiking interneurons (FSIs). In the cortex, this microcircuitry produces gamma oscillations that support information processing and behavior. We tested whether this was similarly the case in the rat (males) LA and BL using extracellular recordings, biophysical modeling, and behavioral conditioning. During periods of environmental assessment, both nuclei exhibited gamma oscillations that stopped upon initiation of active behaviors. Yet, BL exhibited more robust spontaneous gamma oscillations than LA. The greater propensity of BL to generate gamma resulted from several microcircuit differences, especially the proportion of FSIs and their interconnections with principal cells. Furthermore, gamma in BL but not LA regulated the efficacy of excitatory synaptic transmission between connected neurons. Together, these results suggest fundamental differences in how LA and BL operate. Most likely, gamma in LA is externally driven, whereas in BL it can also arise spontaneously to support ruminative processing and the evaluation of complex situations.SIGNIFICANCE STATEMENT The basolateral amygdala (BLA) participates in the production and regulation of emotional behaviors. It is thought to perform this using feedforward circuits that enhance stimuli that gain emotional significance and directs them to valence-appropriate downstream effectors. This perspective overlooks the fact that its microcircuitry is recurrent and potentially capable of generating oscillations in the gamma band (50-80 Hz), which synchronize spiking activity and modulate communication between neurons. This study found that BLA gamma supports both of these processes, is associated with periods of action selection and environmental assessment regardless of valence, and differs between BLA subnuclei in a manner consistent with their heretofore unknown microcircuit differences. Thus, it provides new mechanisms for BLA to support emotional behaviors.
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Affiliation(s)
- Drew B Headley
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, New Jersey 07102
| | - Pinelopi Kyriazi
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, New Jersey 07102
- Behavioral and Neural Sciences Graduate Program, Rutgers University, Newark, New Jersey 07102
| | - Feng Feng
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, Missouri 65211
| | - Satish S Nair
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, Missouri 65211
| | - Denis Pare
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, New Jersey 07102
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13
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Cellular Effects of Rhynchophylline and Relevance to Sleep Regulation. Clocks Sleep 2021; 3:312-341. [PMID: 34207633 PMCID: PMC8293156 DOI: 10.3390/clockssleep3020020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/25/2021] [Accepted: 06/03/2021] [Indexed: 01/06/2023] Open
Abstract
Uncaria rhynchophylla is a plant highly used in the traditional Chinese and Japanese medicines. It has numerous health benefits, which are often attributed to its alkaloid components. Recent studies in humans show that drugs containing Uncaria ameliorate sleep quality and increase sleep time, both in physiological and pathological conditions. Rhynchophylline (Rhy) is one of the principal alkaloids in Uncaria species. Although treatment with Rhy alone has not been tested in humans, observations in rodents show that Rhy increases sleep time. However, the mechanisms by which Rhy could modulate sleep have not been comprehensively described. In this review, we are highlighting cellular pathways that are shown to be targeted by Rhy and which are also known for their implications in the regulation of wakefulness and sleep. We conclude that Rhy can impact sleep through mechanisms involving ion channels, N-methyl-d-aspartate (NMDA) receptors, tyrosine kinase receptors, extracellular signal-regulated kinases (ERK)/mitogen-activated protein kinases (MAPK), phosphoinositide 3-kinase (PI3K)/RAC serine/threonine-protein kinase (AKT), and nuclear factor-kappa B (NF-κB) pathways. In modulating multiple cellular responses, Rhy impacts neuronal communication in a way that could have substantial effects on sleep phenotypes. Thus, understanding the mechanisms of action of Rhy will have implications for sleep pharmacology.
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14
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Wang Y, Tan B, Wang Y, Chen Z. Cholinergic Signaling, Neural Excitability, and Epilepsy. Molecules 2021; 26:molecules26082258. [PMID: 33924731 PMCID: PMC8070422 DOI: 10.3390/molecules26082258] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/09/2021] [Accepted: 04/11/2021] [Indexed: 11/16/2022] Open
Abstract
Epilepsy is a common brain disorder characterized by recurrent epileptic seizures with neuronal hyperexcitability. Apart from the classical imbalance between excitatory glutamatergic transmission and inhibitory γ-aminobutyric acidergic transmission, cumulative evidence suggest that cholinergic signaling is crucially involved in the modulation of neural excitability and epilepsy. In this review, we briefly describe the distribution of cholinergic neurons, muscarinic, and nicotinic receptors in the central nervous system and their relationship with neural excitability. Then, we summarize the findings from experimental and clinical research on the role of cholinergic signaling in epilepsy. Furthermore, we provide some perspectives on future investigation to reveal the precise role of the cholinergic system in epilepsy.
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Affiliation(s)
- Yu Wang
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China; (Y.W.); (B.T.)
| | - Bei Tan
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China; (Y.W.); (B.T.)
| | - Yi Wang
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China; (Y.W.); (B.T.)
- Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310058, China
- Correspondence: (Y.W.); (Z.C.); Tel.: +86-5718-661-8660 (Z.C.)
| | - Zhong Chen
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China; (Y.W.); (B.T.)
- Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310058, China
- Correspondence: (Y.W.); (Z.C.); Tel.: +86-5718-661-8660 (Z.C.)
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15
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Kargl D, Kaczanowska J, Ulonska S, Groessl F, Piszczek L, Lazovic J, Buehler K, Haubensak W. The amygdala instructs insular feedback for affective learning. eLife 2020; 9:60336. [PMID: 33216712 PMCID: PMC7679142 DOI: 10.7554/elife.60336] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 11/04/2020] [Indexed: 12/21/2022] Open
Abstract
Affective responses depend on assigning value to environmental predictors of threat or reward. Neuroanatomically, this affective value is encoded at both cortical and subcortical levels. However, the purpose of this distributed representation across functional hierarchies remains unclear. Using fMRI in mice, we mapped a discrete cortico-limbic loop between insular cortex (IC), central amygdala (CE), and nucleus basalis of Meynert (NBM), which decomposes the affective value of a conditioned stimulus (CS) into its salience and valence components. In IC, learning integrated unconditioned stimulus (US)-evoked bodily states into CS valence. In turn, CS salience in the CE recruited these CS representations bottom-up via the cholinergic NBM. This way, the CE incorporated interoceptive feedback from IC to improve discrimination of CS valence. Consequently, opto-/chemogenetic uncoupling of hierarchical information flow disrupted affective learning and conditioned responding. Dysfunctional interactions in the IC↔CE/NBM network may underlie intolerance to uncertainty, observed in autism and related psychiatric conditions.
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Affiliation(s)
- Dominic Kargl
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Joanna Kaczanowska
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Sophia Ulonska
- VRVis Zentrum für Virtual Reality und Visualisierung Forschungs-GmbH (VRVis), Vienna, Austria
| | - Florian Groessl
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Lukasz Piszczek
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Jelena Lazovic
- Preclinical Imaging Facility (pcIMAG), Vienna Biocenter Core Facilities (VBCF), Vienna, Austria
| | - Katja Buehler
- VRVis Zentrum für Virtual Reality und Visualisierung Forschungs-GmbH (VRVis), Vienna, Austria
| | - Wulf Haubensak
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
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16
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Trompoukis G, Rigas P, Leontiadis LJ, Papatheodoropoulos C. I h, GIRK, and KCNQ/Kv7 channels differently modulate sharp wave - ripples in the dorsal and ventral hippocampus. Mol Cell Neurosci 2020; 107:103531. [PMID: 32711112 DOI: 10.1016/j.mcn.2020.103531] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 07/11/2020] [Accepted: 07/16/2020] [Indexed: 12/14/2022] Open
Abstract
Sharp waves and ripples (SPW-Rs) are endogenous transient patterns of hippocampus local network activity implicated in several functions including memory consolidation, and they are diversified between the dorsal and the ventral hippocampus. Ion channels in the neuronal membrane play important roles in cell and local network function. In this study, using transverse slices and field potential recordings from the CA1 field of rat hippocampus we show that GIRK and KCNQ2/3 potassium channels play a higher role in modulating SPW-Rs in the dorsal hippocampus, while Ih and other KCNQ (presumably KCNQ5) channels, contribute to shaping SPW-R activity more in the ventral than in dorsal hippocampus. Specifically, blockade of Ih channels by ZD 7288 reduced the rate of occurrence of SPW-Rs and increased the generation of SPW-Rs in the form of clusters in both hippocampal segments, while enhanced the amplitude of SPW-Rs only in the ventral hippocampus. Most effects of ZD 7288 appeared to be independent of NMDA receptors' activity. However, the effects of blockade of NMDA receptors depended on the functional state of Ih channels in both hippocampal segments. Blockade of GIRK channels by Tertiapin-Q increased the rate of occurrence of SPW-Rs only in the dorsal hippocampus and the probability of clusters in both segments of the hippocampus. Blockade of KCNQ2/3 channels by XE 991 increased the rate of occurrence of SPW-Rs and the probability of clusters in the dorsal hippocampus, and only reduced the clustered generation of SPW-Rs in the ventral hippocampus. The blocker of KCNQ1/2 channels, that also enhances KCNQ5 channels, UCL 2077, increased the probability of clusters and the power of the ripple oscillation in the ventral hippocampus only. These results suggest that GIRK, KCNQ and Ih channels represent a key mechanism for modulation of SPW-R activity which act differently in the dorsal and ventral hippocampus, fundamentally supporting functional diversification along the dorsal-ventral axis of the hippocampus.
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Affiliation(s)
- George Trompoukis
- Laboratory of Physiology, Department of Medicine, University of Patras, Rion, Greece
| | - Pavlos Rigas
- Laboratory of Physiology, Department of Medicine, University of Patras, Rion, Greece
| | - Leonidas J Leontiadis
- Laboratory of Physiology, Department of Medicine, University of Patras, Rion, Greece
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17
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Fernández de Sevilla D, Núñez A, Buño W. Muscarinic Receptors, from Synaptic Plasticity to its Role in Network Activity. Neuroscience 2020; 456:60-70. [PMID: 32278062 DOI: 10.1016/j.neuroscience.2020.04.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 03/27/2020] [Accepted: 04/01/2020] [Indexed: 12/13/2022]
Abstract
Acetylcholine acting via metabotropic receptors plays a key role in learning and memory by regulating synaptic plasticity and circuit activity. However, a recent overall view of the effects of muscarinic acetylcholine receptors (mAChRs) on excitatory and inhibitory long-term synaptic plasticity and on circuit activity is lacking. This review focusses on specific aspects of the regulation of synaptic plasticity and circuit activity by mAChRs in the hippocampus and cortex. Acetylcholine increases the excitability of pyramidal neurons, facilitating the generation of dendritic Ca2+-spikes, NMDA-spikes and action potential bursts which provide the main source of Ca2+ influx necessary to induce synaptic plasticity. The activation of mAChRs induced Ca2+ release from intracellular IP3-sensitive stores is a major player in the induction of a NMDA independent long-term potentiation (LTP) caused by an increased expression of AMPA receptors in hippocampal pyramidal neuron dendritic spines. In the neocortex, activation of mAChRs also induces a long-term enhancement of excitatory postsynaptic currents. In addition to effects on excitatory synapses, a single brief activation of mAChRs together with short repeated membrane depolarization can induce a long-term enhancement of GABA A type (GABAA) inhibition through an increased expression of GABAA receptors in hippocampal pyramidal neurons. By contrast, a long term depression of GABAA inhibition (iLTD) is induced by muscarinic receptor activation in the absence of postsynaptic depolarizations. This iLTD is caused by an endocannabinoid-mediated presynaptic inhibition that reduces the GABA release probability at the terminals of inhibitory interneurons. This bidirectional long-term plasticity of inhibition may dynamically regulate the excitatory/inhibitory balance depending on the quiescent or active state of the postsynaptic pyramidal neurons. Therefore, acetylcholine can induce varied effects on neuronal activity and circuit behavior that can enhance sensory detection and processing through the modification of circuit activity leading to learning, memory and behavior.
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Affiliation(s)
- D Fernández de Sevilla
- Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid 28029, Spain.
| | - A Núñez
- Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid 28029, Spain
| | - W Buño
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, Madrid 28029, Spain
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18
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Crans RAJ, Wouters E, Valle-León M, Taura J, Massari CM, Fernández-Dueñas V, Stove CP, Ciruela F. Striatal Dopamine D 2-Muscarinic Acetylcholine M 1 Receptor-Receptor Interaction in a Model of Movement Disorders. Front Pharmacol 2020; 11:194. [PMID: 32231561 PMCID: PMC7083216 DOI: 10.3389/fphar.2020.00194] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 02/11/2020] [Indexed: 12/17/2022] Open
Abstract
Parkinson’s disease (PD) is a neurodegenerative disorder characterized by motor control deficits, which is associated with the loss of striatal dopaminergic neurons from the substantia nigra. In parallel to dopaminergic denervation, there is an increase of acetylcholine within the striatum, resulting in a striatal dopaminergic–cholinergic neurotransmission imbalance. Currently, available PD pharmacotherapy (e.g., prodopaminergic drugs) does not reinstate the altered dopaminergic–cholinergic balance. In addition, it can eventually elicit cholinergic-related adverse effects. Here, we investigated the interplay between dopaminergic and cholinergic systems by assessing the physical and functional interaction of dopamine D2 and muscarinic acetylcholine M1 receptors (D2R and M1R, respectively), both expressed at striatopallidal medium spiny neurons. First, we provided evidence for the existence of D2R–M1R complexes via biochemical (i.e., co-immunoprecipitation) and biophysical (i.e., BRET1 and NanoBiT®) assays, performed in transiently transfected HEK293T cells. Subsequently, a D2R–M1R co-distribution in the mouse striatum was observed through double-immunofluorescence staining and AlphaLISA® immunoassay. Finally, we evaluated the functional interplay between both receptors via behavioral studies, by implementing the classical acute reserpine pharmacological animal model of experimental parkinsonism. Reserpinized mice were administered with a D2R-selective agonist (sumanirole) and/or an M1R-selective antagonist (VU0255035), and alterations in PD-related behavioral tasks (i.e., locomotor activity) were evaluated. Importantly, VU0255035 (10 mg/kg) potentiated the antiparkinsonian-like effects (i.e., increased locomotor activity and decreased catalepsy) of an ineffective sumanirole dose (3 mg/kg). Altogether, our data suggest the existence of putative striatal D2R/M1R heteromers, which might be a relevant target to manage PD motor impairments with fewer adverse effects.
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Affiliation(s)
- René A J Crans
- Laboratory of Toxicology, Department of Bioanalysis, Ghent University, Ghent, Belgium.,Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Elise Wouters
- Laboratory of Toxicology, Department of Bioanalysis, Ghent University, Ghent, Belgium
| | - Marta Valle-León
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Jaume Taura
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Caio M Massari
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Programa de Poìs-graduação em Bioquiìmica, Centro de Ciencias Bioloìgicas, Universidade Federal de Santa Catarina, Florianoìpolis, Brazil
| | - Víctor Fernández-Dueñas
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Christophe P Stove
- Laboratory of Toxicology, Department of Bioanalysis, Ghent University, Ghent, Belgium
| | - Francisco Ciruela
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
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19
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Mysin IE, Kitchigina VF, Kazanovich YB. Phase relations of theta oscillations in a computer model of the hippocampal CA1 field: Key role of Schaffer collaterals. Neural Netw 2019; 116:119-138. [DOI: 10.1016/j.neunet.2019.04.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 03/29/2019] [Accepted: 04/02/2019] [Indexed: 02/04/2023]
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20
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Bjorefeldt A, Roshan F, Forsberg M, Zetterberg H, Hanse E, Fisahn A. Human cerebrospinal fluid promotes spontaneous gamma oscillations in the hippocampus in vitro. Hippocampus 2019; 30:101-113. [PMID: 31313871 DOI: 10.1002/hipo.23135] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 06/11/2019] [Accepted: 06/12/2019] [Indexed: 01/23/2023]
Abstract
Gamma oscillations (30-80 Hz) are fast network activity patterns frequently linked to cognition. They are commonly studied in hippocampal brain slices in vitro, where they can be evoked via pharmacological activation of various receptor families. One limitation of this approach is that neuronal activity is studied in a highly artificial extracellular fluid environment, as provided by artificial cerebrospinal fluid (aCSF). Here, we examine the influence of human cerebrospinal fluid (hCSF) on kainate-evoked and spontaneous gamma oscillations in mouse hippocampus. We show that hCSF, as compared to aCSF of matched electrolyte and glucose composition, increases the power of kainate-evoked gamma oscillations and induces spontaneous gamma activity in areas CA3 and CA1 that is reversed by washout. Bath application of atropine entirely abolished hCSF-induced gamma oscillations, indicating critical contribution from muscarinic acetylcholine receptor-mediated signaling. In separate whole-cell patch clamp recordings from rat hippocampus, hCSF increased theta resonance frequency and strength in pyramidal cells along with enhancement of h-current (Ih ) amplitude. We found no evidence of intrinsic gamma frequency resonance at baseline (aCSF) among fast-spiking interneurons, and this was not altered by hCSF. However, hCSF increased the excitability of fast-spiking interneurons, which likely contributed to gamma rhythmogenesis. Our findings show that hCSF promotes network gamma oscillations in the hippocampus in vitro and suggest that neuromodulators distributed in CSF could have significant influence on neuronal network activity in vivo.
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Affiliation(s)
- Andreas Bjorefeldt
- Department of Physiology, Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden.,Department of Neuroscience, Brown University, Providence, Rhode Island
| | - Firoz Roshan
- Neuronal Oscillations Laboratory, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - My Forsberg
- Department of Physiology, Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, Molndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Molndal, Sweden.,Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK.,UK Dementia Research Institute at UCL, London, UK
| | - Eric Hanse
- Department of Physiology, Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden
| | - André Fisahn
- Neuronal Oscillations Laboratory, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
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21
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The M 1 muscarinic acetylcholine receptor subtype is important for retinal neuron survival in aging mice. Sci Rep 2019; 9:5222. [PMID: 30914695 PMCID: PMC6435680 DOI: 10.1038/s41598-019-41425-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 03/04/2019] [Indexed: 01/19/2023] Open
Abstract
Muscarinic acetylcholine receptors have been implicated as potential neuroprotective targets for glaucoma. We tested the hypothesis that the lack of a single muscarinic receptor subtype leads to age-dependent neuron reduction in the retinal ganglion cell layer. Mice with targeted disruption of single muscarinic acetylcholine receptor subtype genes (M1 to M5) and wild-type controls were examined at two age categories, 5 and 15 months, respectively. We found no differences in intraocular pressure between individual mouse groups. Remarkably, in 15-month-old mice devoid of the M1 receptor, neuron number in the retinal ganglion cell layer and axon number in the optic nerve were markedly reduced. Moreover, mRNA expression for the prooxidative enzyme, NOX2, was increased, while mRNA expression for the antioxidative enzymes, SOD1, GPx1 and HO-1, was reduced in aged M1 receptor-deficient mice compared to age-matched wild-type mice. In line with these findings, the reactive oxygen species level was also elevated in the retinal ganglion cell layer of aged M1 receptor-deficient mice. In conclusion, M1 receptor deficiency results in retinal ganglion cell loss in aged mice via involvement of oxidative stress. Based on these findings, activation of M1 receptor signaling may become therapeutically useful to promote retinal ganglion cell survival.
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22
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van Lier B, Hierlemann A, Knoflach F. Parvalbumin expression and gamma oscillation occurrence increase over time in a neurodevelopmental model of NMDA receptor dysfunction. PeerJ 2018; 6:e5543. [PMID: 30258707 PMCID: PMC6151115 DOI: 10.7717/peerj.5543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 08/07/2018] [Indexed: 11/20/2022] Open
Abstract
Dysfunction of the N-methyl-d-aspartate receptor (NMDAR) is thought to play a role in the pathophysiology of neurodevelopmental diseases like schizophrenia. To study the effects of NMDAR dysfunction on synaptic transmission and network oscillations, we used hippocampal tissue of NMDAR subunit GluN2A knockout (KO) mice. Field excitatory postsynaptic potentials were recorded in acute hippocampal slices of adult animals. Synaptic transmission was impaired in GluN2A KO slices compared to wild-type (WT) slices. Further, to investigate whether NMDAR dysfunction would alter neurodevelopment in vitro, we used organotypic hippocampal slice cultures of WT and GluN2A KO mice. Immunostaining performed with cultures kept two, seven, 14, 25 days in vitro (DIV) revealed an increasing expression of parvalbumin (PV) over time. As a functional readout, oscillatory activity induced by the cholinergic agonist carbachol was recorded in cultures kept seven, 13, and 26 DIV using microelectrode arrays. Initial analysis focused on the occurrence of delta, theta, beta and gamma oscillations over genotype, DIV and hippocampal area (CA1, CA3, dentate gyrus (DG)). In a follow-up analysis, we studied the peak frequency and the peak power of each of the four oscillation bands per condition. The occurrence of gamma oscillations displayed an increase by DIV similar to the PV immunostaining. Unlike gamma occurrence, delta, theta, and beta occurrence did not change over time in culture. The peak frequency and peak power in the different bands of the oscillations were not different in slices of WT and GluN2A KO mice. However, the level of PV expression was lower in GluN2A KO compared to WT mice. Given the role of PV-containing fast-spiking basket cells in generation of oscillations and the decreased PV expression in subjects with schizophrenia, the study of gamma oscillations in organotypic hippocampal slices represents a potentially valuable tool for the characterization of novel therapeutic drugs.
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Affiliation(s)
- Ben van Lier
- Neuroscience Discovery, Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland.,Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Andreas Hierlemann
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Frédéric Knoflach
- Neuroscience Discovery, Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
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23
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Myslivecek J, Farar V, Valuskova P. M(4) muscarinic receptors and locomotor activity regulation. Physiol Res 2018; 66:S443-S455. [PMID: 29355372 DOI: 10.33549/physiolres.933796] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
M(4) muscarinic receptors (M(4) MR) represent a subfamily of G-protein coupled receptors serving a substantial role in spontaneous locomotor activity regulation, cognition and modulation of cholinergic system. With increasing body of literature discussing the role of M(4) MR some controversies arose. Thus, we try here to summarize the current evidence regarding the M(4) MR, with the special focus on their role in Locomotor activity control. We review the molecular function of M(4) MR in specific brain areas implicated in locomotor regulation, and shortly in other CNS processes that could be connected to locomotor activity. We also focus on brain areas implicated in locomotor activity biorhythm changes like suprachiasmatic nucleus, subparaventricular zone posterior hypothalamic area, striatum and thalamus. Gender-related aspects and differences in locomotor activity in males and females are discussed further.
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Affiliation(s)
- J Myslivecek
- Institute of Physiology, First Faculty of Medicine, Charles University, Prague, Czech Republic.
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24
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Oda S, Tsuneoka Y, Yoshida S, Adachi-Akahane S, Ito M, Kuroda M, Funato H. Immunolocalization of muscarinic M1 receptor in the rat medial prefrontal cortex. J Comp Neurol 2018; 526:1329-1350. [PMID: 29424434 PMCID: PMC5900831 DOI: 10.1002/cne.24409] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 01/23/2018] [Accepted: 01/27/2018] [Indexed: 12/20/2022]
Abstract
The medial prefrontal cortex (mPFC) has been considered to participate in many higher cognitive functions, such as memory formation and spatial navigation. These cognitive functions are modulated by cholinergic afferents via muscarinic acetylcholine receptors. Previous pharmacological studies have strongly suggested that the M1 receptor (M1R) is the most important subtype among muscarinic receptors to perform these cognitive functions. Actually, M1R is abundant in mPFC. However, the proportion of somata containing M1R among cortical cellular types, and the precise intracellular localization of M1R remain unclear. In this study, to clarify the precise immunolocalization of M1R in rat mPFC, we examined three major cellular types, pyramidal neurons, inhibitory neurons, and astrocytes. M1R immunopositivity signals were found in the majority of the somata of both pyramidal neurons and inhibitory neurons. In pyramidal neurons, strong M1R immunopositivity signals were usually found throughout their somata and dendrites including spines. On the other hand, the signal strength of M1R immunopositivity in the somata of inhibitory neurons significantly varied. Some neurons showed strong signals. Whereas about 40% of GAD67‐immunopositive neurons and 30% of parvalbumin‐immunopositive neurons (PV neurons) showed only weak signals. In PV neurons, M1R immunopositivity signals were preferentially distributed in somata. Furthermore, we found that many astrocytes showed substantial M1R immunopositivity signals. These signals were also mainly distributed in their somata. Thus, the distribution pattern of M1R markedly differs between cellular types. This difference might underlie the cholinergic modulation of higher cognitive functions subserved by mPFC.
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Affiliation(s)
- Satoko Oda
- Department of Anatomy, Faculty of Medicine, Toho University, Tokyo, 143-8540, Japan
| | - Yousuke Tsuneoka
- Department of Anatomy, Faculty of Medicine, Toho University, Tokyo, 143-8540, Japan
| | - Sachine Yoshida
- Department of Anatomy, Faculty of Medicine, Toho University, Tokyo, 143-8540, Japan.,Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency, Saitama, 332-0012, Japan
| | - Satomi Adachi-Akahane
- Department of Physiology, Faculty of Medicine, Toho University, Tokyo, 143-8540, Japan
| | - Masanori Ito
- Department of Physiology, Faculty of Medicine, Toho University, Tokyo, 143-8540, Japan
| | - Masaru Kuroda
- Department of Anatomy, Faculty of Medicine, Toho University, Tokyo, 143-8540, Japan
| | - Hiromasa Funato
- Department of Anatomy, Faculty of Medicine, Toho University, Tokyo, 143-8540, Japan.,International institute for integrative sleep medicine (IIIS), Tsukuba University, Ibaraki, 305-8575, Japan
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25
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Deckmann K, Rafiq A, Erdmann C, Illig C, Durschnabel M, Wess J, Weidner W, Bschleipfer T, Kummer W. Muscarinic receptors 2 and 5 regulate bitter response of urethral brush cells via negative feedback. FASEB J 2018; 32:2903-2910. [PMID: 29401598 DOI: 10.1096/fj.201700582r] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
We have recently identified a cholinergic chemosensory cell in the urethral epithelium, urethral brush cell (UBC), that, upon stimulation with bitter or bacterial substances, initiates a reflex detrusor activation. Here, we elucidated cholinergic mechanisms that modulate UBC responsiveness. We analyzed muscarinic acetylcholine receptor (M1-5 mAChR) expression by using RT-PCR in UBCs, recorded [Ca2+]i responses to a bitter stimulus in isolated UBCs of wild-type and mAChR-deficient mice, and performed cystometry in all involved strains. The bitter response of UBCs was enhanced by global cholinergic and selective M2 inhibition, diminished by positive allosteric modulation of M5, and unaffected by M1, M3, and M4 mAChR inhibitors. This effect was not observed in M2 and M5 mAChR-deficient mice. In cystometry, M5 mAChR-deficient mice demonstrated signs of detrusor overactivity. In conclusion, M2 and M5 mAChRs attenuate the bitter response of UBC via a cholinergic negative autocrine feedback mechanism. Cystometry suggests that dysfunction, particularly of the M5 receptor, may lead to such symptoms as bladder overactivity.-Deckmann, K., Rafiq, A., Erdmann, C., Illig, C., Durschnabel, M., Wess, J., Weidner, W., Bschleipfer, T., Kummer, W. Muscarinic receptors 2 and 5 regulate bitter response of urethral brush cells via negative feedback.
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Affiliation(s)
- Klaus Deckmann
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Amir Rafiq
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Christian Erdmann
- Department of Urology, Pediatric Urology, and Andrology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Christian Illig
- Department of Urology, Pediatric Urology, and Andrology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Melanie Durschnabel
- Department of Urology, Pediatric Urology, and Andrology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA
| | - Wolfgang Weidner
- Department of Urology, Pediatric Urology, and Andrology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Thomas Bschleipfer
- Clinic of Urology, Andrology, and Pediatric Urology, Weiden Hospital/Clinics of Nordoberpfalz AG, Weiden, Germany
| | - Wolfgang Kummer
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
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26
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Dheerendra P, Lynch NM, Crutwell J, Cunningham MO, Smulders TV. In vitro characterization of gamma oscillations in the hippocampal formation of the domestic chick. Eur J Neurosci 2018; 48:2807-2815. [PMID: 29120510 PMCID: PMC6220815 DOI: 10.1111/ejn.13773] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 10/28/2017] [Accepted: 11/02/2017] [Indexed: 11/30/2022]
Abstract
Avian and mammalian brains have evolved independently from each other for about 300 million years. During that time, the hippocampal formation (HF) has diverged in morphology and cytoarchitecture, but seems to have conserved much of its function. It is therefore an open question how seemingly different neural organizations can generate the same function. A prominent feature of the mammalian hippocampus is that it generates different neural oscillations, including the gamma rhythm, which plays an important role in memory processing. In this study, we investigate whether the avian hippocampus also generates gamma oscillations, and whether similar pharmacological mechanisms are involved in this function. We investigated the existence of gamma oscillations in avian HF using in vitro electrophysiology in P0–P12 domestic chick (Gallus gallus domesticus) HF brain slices. Persistent gamma frequency oscillations were induced by the bath application of the cholinergic agonist carbachol, but not by kainate, a glutamate receptor agonist. Similar to other species, carbachol‐evoked gamma oscillations were sensitive to GABAA, AMPA/kainate and muscarinic (M1) receptor antagonism. Therefore, similar to mammalian species, muscarinic receptor‐activated avian HF gamma oscillations may arise via a pyramidal‐interneuron gamma (PING)‐based mechanism. Gamma oscillations are most prominent in the ventromedial area of the hippocampal slices, and gamma power is reduced more laterally and dorsally in the HF. We conclude that similar micro‐circuitry may exist in the avian and mammalian hippocampal formation, and this is likely to relate to the shared function of the two structures.
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Affiliation(s)
- Pradeep Dheerendra
- Institute of Neuroscience, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Nicholas M Lynch
- Institute of Neuroscience, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.,University of Louisville, Louisville, KY, USA
| | - Joseph Crutwell
- Institute of Neuroscience, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Mark O Cunningham
- Institute of Neuroscience, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Tom V Smulders
- Institute of Neuroscience, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.,Centre for Behaviour and Evolution, Newcastle University, Newcastle upon Tyne, UK
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27
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Thomsen M, Sørensen G, Dencker D. Physiological roles of CNS muscarinic receptors gained from knockout mice. Neuropharmacology 2017; 136:411-420. [PMID: 28911965 DOI: 10.1016/j.neuropharm.2017.09.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 09/06/2017] [Accepted: 09/08/2017] [Indexed: 12/29/2022]
Abstract
Because the five muscarinic acetylcholine receptor subtypes have overlapping distributions in many CNS tissues, and because ligands with a high degree of selectivity for a given subtype long remained elusive, it has been difficult to determine the physiological functions of each receptor. Genetically engineered knockout mice, in which one or more muscarinic acetylcholine receptor subtype has been inactivated, have been instrumental in identifying muscarinic receptor functions in the CNS, at the neuronal, circuit, and behavioral level. These studies revealed important functions of muscarinic receptors modulating neuronal activity and neurotransmitter release in many brain regions, shaping neuronal plasticity, and affecting functions ranging from motor and sensory function to cognitive processes. As gene targeting technology evolves including the use of conditional, cell type specific strains, knockout mice are likely to continue to provide valuable insights into brain physiology and pathophysiology, and advance the development of new medications for a range of conditions such as Alzheimer's disease, Parkinson's disease, schizophrenia, and addictions, as well as non-opioid analgesics. This article is part of the Special Issue entitled 'Neuropharmacology on Muscarinic Receptors'.
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Affiliation(s)
- Morgane Thomsen
- Laboratory of Neuropsychiatry, Psychiatric Center Copenhagen and University of Copenhagen, Denmark; Alcohol and Drug Abuse Research Center, McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA.
| | - Gunnar Sørensen
- Alcohol and Drug Abuse Research Center, McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA
| | - Ditte Dencker
- Laboratory of Neuropsychiatry, Psychiatric Center Copenhagen and University of Copenhagen, Denmark
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28
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Thorn CA, Popiolek M, Stark E, Edgerton JR. Effects of M1 and M4 activation on excitatory synaptic transmission in CA1. Hippocampus 2017; 27:794-810. [PMID: 28422371 PMCID: PMC5573954 DOI: 10.1002/hipo.22732] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 02/24/2017] [Accepted: 03/31/2017] [Indexed: 01/23/2023]
Abstract
Hippocampal networks are particularly susceptible to dysfunction in many neurodegenerative diseases and neuropsychiatric disorders including Alzheimer's disease, Lewy body dementia, and schizophrenia. CA1, a major output region of the hippocampus, receives glutamatergic input from both hippocampal CA3 and entorhinal cortex, via the Schaffer collateral (SC) and temporoammonic (TA) pathways, respectively. SC and TA inputs to CA1 are thought to be differentially involved in the retrieval of previously stored memories versus the encoding of novel information, and switching between these two crucial hippocampal functions is thought to critically depend on acetylcholine (ACh) acting at muscarinic receptors. In this study, we aimed to determine the roles of specific subtypes of muscarinic receptors in mediating the neuromodulatory effects of ACh on glutamatergic synaptic transmission in the SC and TA pathways of CA1. Using selective pharmacological activation of M1 or M4 receptors along with extracellular and intracellular electrophysiology recordings from adult rat hippocampal slices, we demonstrate that activation of M1 receptors increases spontaneous spike rates of neuronal ensembles in CA1 and increases the intrinsic excitability of pyramidal neurons and interneurons. Selective activation of M4 receptors inhibits glutamate release in the SC pathway, while leaving synaptic transmission in the TA pathway comparatively intact. These results suggest specific mechanisms by which M1 and M4 activation may normalize CA1 circuit activity following disruptions of signaling that accompany neurodegenerative dementias or neuropsychiatric disorders. These findings are of particular interest in light of clinical findings that xanomeline, an M1/M4 preferring agonist, was able to improve cognitive and behavioral symptoms in patients with Alzheimer's disease or schizophrenia.
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Affiliation(s)
| | - Michael Popiolek
- Pfizer Internal Medicine Research UnitCambridgeMassachusetts02139
| | - Eda Stark
- Pfizer Internal Medicine Research UnitCambridgeMassachusetts02139
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29
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Wang Q, Yue WWS, Jiang Z, Xue T, Kang SH, Bergles DE, Mikoshiba K, Offermanns S, Yau KW. Synergistic Signaling by Light and Acetylcholine in Mouse Iris Sphincter Muscle. Curr Biol 2017; 27:1791-1800.e5. [PMID: 28578927 PMCID: PMC8577559 DOI: 10.1016/j.cub.2017.05.022] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 04/04/2017] [Accepted: 05/05/2017] [Indexed: 01/29/2023]
Abstract
The mammalian pupillary light reflex (PLR) involves a bilateral brain circuit whereby afferent light signals in the optic nerve ultimately drive iris-sphincter-muscle contraction via excitatory cholinergic parasympathetic innervation [1, 2]. Additionally, the PLR in nocturnal and crepuscular sub-primate mammals has a "local" component in the isolated sphincter muscle [3-5], as in amphibians, fish, and bird [6-10]. In mouse, this local PLR requires the pigment melanopsin [5], originally found in intrinsically photosensitive retinal ganglion cells (ipRGCs) [11-19]. However, melanopsin's presence and effector pathway locally in the iris remain uncertain. The sphincter muscle itself may express melanopsin [5], or its cholinergic parasympathetic innervation may be modulated by suggested intraocular axonal collaterals of ipRGCs traveling to the eye's ciliary body or even to the iris [20-22]. Here, we show that the muscarinic receptor antagonist, atropine, eliminated the effect of acetylcholine (ACh), but not of light, on isolated mouse sphincter muscle. Conversely, selective genetic deletion of melanopsin in smooth muscle mostly removed the light-induced, but not the ACh-triggered, increase in isolated sphincter muscle's tension and largely suppressed the local PLR in vivo. Thus, sphincter muscle cells are bona fide, albeit unconventional, photoreceptors. We found melanopsin expression in a small subset of mouse iris sphincter muscle cells, with the light-induced contractile signal apparently spreading through gap junctions into neighboring muscle cells. Light and ACh share a common signaling pathway in sphincter muscle. In summary, our experiments have provided details of a photosignaling process in the eye occurring entirely outside the retina.
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Affiliation(s)
- Qian Wang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Sensory Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Biochemistry, Cellular, and Molecular Biology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Wendy Wing Sze Yue
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Sensory Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Biochemistry, Cellular, and Molecular Biology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Zheng Jiang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Sensory Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Tian Xue
- Chinese Academy of Science Key Laboratory of Brain Function and Diseases, School of Life Sciences, University of Science and Technology of China, Hefei 230027, Anhui, PRC
| | - Shin H Kang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Dwight E Bergles
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Saitama 351-0198, Japan
| | - Stefan Offermanns
- Max-Planck-Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - King-Wai Yau
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Sensory Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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30
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Betterton RT, Broad LM, Tsaneva‐Atanasova K, Mellor JR. Acetylcholine modulates gamma frequency oscillations in the hippocampus by activation of muscarinic M1 receptors. Eur J Neurosci 2017; 45:1570-1585. [PMID: 28406538 PMCID: PMC5518221 DOI: 10.1111/ejn.13582] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 04/04/2017] [Accepted: 04/07/2017] [Indexed: 12/21/2022]
Abstract
Modulation of gamma oscillations is important for the processing of information and the disruption of gamma oscillations is a prominent feature of schizophrenia and Alzheimer's disease. Gamma oscillations are generated by the interaction of excitatory and inhibitory neurons where their precise frequency and amplitude are controlled by the balance of excitation and inhibition. Acetylcholine enhances the intrinsic excitability of pyramidal neurons and suppresses both excitatory and inhibitory synaptic transmission, but the net modulatory effect on gamma oscillations is not known. Here, we find that the power, but not frequency, of optogenetically induced gamma oscillations in the CA3 region of mouse hippocampal slices is enhanced by low concentrations of the broad‐spectrum cholinergic agonist carbachol but reduced at higher concentrations. This bidirectional modulation of gamma oscillations is replicated within a mathematical model by neuronal depolarisation, but not by reducing synaptic conductances, mimicking the effects of muscarinic M1 receptor activation. The predicted role for M1 receptors was supported experimentally; bidirectional modulation of gamma oscillations by acetylcholine was replicated by a selective M1 receptor agonist and prevented by genetic deletion of M1 receptors. These results reveal that acetylcholine release in CA3 of the hippocampus modulates gamma oscillation power but not frequency in a bidirectional and dose‐dependent manner by acting primarily through muscarinic M1 receptors.
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Affiliation(s)
- Ruth T. Betterton
- Centre for Synaptic PlasticitySchool of Physiology, Pharmacology and NeuroscienceUniversity of BristolBristolBS8 1TDUK
| | | | - Krasimira Tsaneva‐Atanasova
- Department of MathematicsCollege of Engineering, Mathematics and Physical SciencesUniversity of ExeterExeterEX4 4QFUK
| | - Jack R. Mellor
- Centre for Synaptic PlasticitySchool of Physiology, Pharmacology and NeuroscienceUniversity of BristolBristolBS8 1TDUK
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31
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Lv X, Dickerson JW, Rook JM, Lindsley CW, Conn PJ, Xiang Z. M 1 muscarinic activation induces long-lasting increase in intrinsic excitability of striatal projection neurons. Neuropharmacology 2017; 118:209-222. [PMID: 28336323 DOI: 10.1016/j.neuropharm.2017.03.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2016] [Revised: 02/20/2017] [Accepted: 03/15/2017] [Indexed: 01/11/2023]
Abstract
The dorsolateral striatum is critically involved in movement control and motor learning. Striatal function is regulated by a variety of neuromodulators including acetylcholine. Previous studies have shown that cholinergic activation excites striatal principal projection neurons, medium spiny neurons (MSNs), and this action is mediated by muscarinic acetylcholine subtype 1 receptors (M1) through modulating multiple potassium channels. In the present study, we used electrophysiology techniques in conjunction with optogenetic and pharmacological tools to determine the long-term effects of striatal cholinergic activation on MSN intrinsic excitability. A transient increase in acetylcholine release in the striatum by optogenetic stimulation resulted in a long-lasting increase in excitability of MSNs, which was associated with hyperpolarizing shift of action potential threshold and decrease in afterhyperpolarization (AHP) amplitude, leading to an increase in probability of EPSP-action potential coupling. The M1 selective antagonist VU0255035 prevented, while the M1 selective positive allosteric modulator (PAM) VU0453595 potentiated the cholinergic activation-induced persistent increase in MSN intrinsic excitability, suggesting that M1 receptors are critically involved in the induction of this long-lasting response. This M1 receptor-dependent long-lasting change in MSN intrinsic excitability could have significant impact on striatal processing and might provide a novel mechanism underlying cholinergic regulation of the striatum-dependent motor learning and cognitive function. Consistent with this, behavioral studies indicate that potentiation of M1 receptor signaling by VU0453595 enhanced performance of mice in cue-dependent water-based T-maze, a dorsolateral striatum-dependent learning task.
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Affiliation(s)
- Xiaohui Lv
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Jonathan W Dickerson
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Jerri M Rook
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Craig W Lindsley
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Department of Chemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - P Jeffrey Conn
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Zixiu Xiang
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA.
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32
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Andersson R, Galter D, Papadia D, Fisahn A. Histamine induces KCNQ channel-dependent gamma oscillations in rat hippocampus via activation of the H1 receptor. Neuropharmacology 2017; 118:13-25. [PMID: 28274820 DOI: 10.1016/j.neuropharm.2017.03.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 03/01/2017] [Accepted: 03/02/2017] [Indexed: 11/30/2022]
Abstract
Histamine is an aminergic neurotransmitter, which regulates wakefulness, arousal and attention in the central nervous system. Histamine receptors have been the target of efforts to develop pro-cognitive drugs to treat disorders such as Alzheimer's disease and schizophrenia. Cognitive functions including attention are closely associated with gamma oscillations, a rhythmical electrical activity pattern in the 30-80 Hz range, which depends on the synchronized activity of excitatory pyramidal cells and inhibitory fast-spiking interneurons. We set out to explore whether histamine has a role in promoting gamma oscillations in the hippocampus. Using in-situ hybridization we demonstrate that histamine receptor subtypes 1, 2 and 3 are expressed in stratum pyramidale of area CA3 in rats. We show that both pyramidal cells and fast-spiking interneurons depolarize and increase action potential firing in response to histamine in vitro. The activation of histamine receptors generates dose-dependent, transient gamma oscillations in area CA3 of the hippocampus - the locus of the gamma rhythm generator. We also demonstrate that this histamine effect is independent of muscarinic receptors. Using specific antagonists we provide evidence that histamine gamma rhythmogenesis specifically depends on the H1 receptor. Histamine also depolarized both pyramidal cells and fast-spiking interneurons and increased membrane resistance in pyramidal cells. The increased membrane resistance is potentially mediated by the inhibition of potassium channels because application of the KCNQ channel opener ICA110381 abolished the oscillations. Taken together our data demonstrate a novel and physiological mechanism for generating gamma oscillations in hippocampus and suggest a role for KCNQ channels in this cognition-relevant brain activity.
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Affiliation(s)
- Richard Andersson
- Neuronal Oscillations Laboratory, Neurogeriatrics Division, Center for Alzheimer Research, Dept. of Neurobiology, Care Sciences and Society, Karolinska Institutet, 14186 Stockholm, Sweden
| | - Dagmar Galter
- Dept. of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Daniela Papadia
- Neuronal Oscillations Laboratory, Neurogeriatrics Division, Center for Alzheimer Research, Dept. of Neurobiology, Care Sciences and Society, Karolinska Institutet, 14186 Stockholm, Sweden
| | - André Fisahn
- Neuronal Oscillations Laboratory, Neurogeriatrics Division, Center for Alzheimer Research, Dept. of Neurobiology, Care Sciences and Society, Karolinska Institutet, 14186 Stockholm, Sweden.
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Radzicki D, Pollema-Mays SL, Sanz-Clemente A, Martina M. Loss of M1 Receptor Dependent Cholinergic Excitation Contributes to mPFC Deactivation in Neuropathic Pain. J Neurosci 2017; 37:2292-2304. [PMID: 28137966 PMCID: PMC5354343 DOI: 10.1523/jneurosci.1553-16.2017] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 12/01/2016] [Accepted: 01/05/2017] [Indexed: 11/21/2022] Open
Abstract
In chronic pain, the medial prefrontal cortex (mPFC) is deactivated and mPFC-dependent tasks such as attention and working memory are impaired. We investigated the mechanisms of mPFC deactivation in the rat spared nerve injury (SNI) model of neuropathic pain. Patch-clamp recordings in acute slices showed that, 1 week after the nerve injury, cholinergic modulation of layer 5 (L5) pyramidal neurons was severely impaired. In cells from sham-operated animals, focal application of acetylcholine induced a left shift of the input/output curve and persistent firing. Both of these effects were almost completely abolished in cells from SNI-operated rats. The cause of this impairment was an ∼60% reduction of an M1-coupled, pirenzepine-sensitive depolarizing current, which appeared to be, at least in part, the consequence of M1 receptor internalization. Although no changes were detected in total M1 protein or transcript, both the fraction of the M1 receptor in the synaptic plasma membrane and the biotinylated M1 protein associated with the total plasma membrane were decreased in L5 mPFC of SNI rats. The loss of excitatory cholinergic modulation may play a critical role in mPFC deactivation in neuropathic pain and underlie the mPFC-specific cognitive deficits that are comorbid with neuropathic pain.SIGNIFICANCE STATEMENT The medial prefrontal cortex (mPFC) undergoes major reorganization in chronic pain. Deactivation of mPFC output is causally correlated with both the cognitive and the sensory component of neuropathic pain. Here, we show that cholinergic excitation of commissural layer 5 mPFC pyramidal neurons is abolished in neuropathic pain rats due to a severe reduction of a muscarinic depolarizing current and M1 receptor internalization. Therefore, in neuropathic pain rats, the acetylcholine (ACh)-dependent increase in neuronal excitability is reduced dramatically and the ACh-induced persisting firing, which is critical for working memory, is abolished. We propose that the blunted cholinergic excitability contributes to the functional mPFC deactivation that is causal for the pain phenotype and represents a cellular mechanism for the attention and memory impairments comorbid with chronic pain.
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Affiliation(s)
| | | | - Antonio Sanz-Clemente
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
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Yaksh TL, Fisher CJ, Hockman TM, Wiese AJ. Current and Future Issues in the Development of Spinal Agents for the Management of Pain. Curr Neuropharmacol 2017; 15:232-259. [PMID: 26861470 PMCID: PMC5412694 DOI: 10.2174/1570159x14666160307145542] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 12/02/2015] [Accepted: 02/05/2016] [Indexed: 11/22/2022] Open
Abstract
Targeting analgesic drugs for spinal delivery reflects the fact that while the conscious experience of pain is mediated supraspinally, input initiated by high intensity stimuli, tissue injury and/or nerve injury is encoded at the level of the spinal dorsal horn and this output informs the brain as to the peripheral environment. This encoding process is subject to strong upregulation resulting in hyperesthetic states and downregulation reducing the ongoing processing of nociceptive stimuli reversing the hyperesthesia and pain processing. The present review addresses the biology of spinal nociceptive processing as relevant to the effects of intrathecally-delivered drugs in altering pain processing following acute stimulation, tissue inflammation/injury and nerve injury. The review covers i) the major classes of spinal agents currently employed as intrathecal analgesics (opioid agonists, alpha 2 agonists; sodium channel blockers; calcium channel blockers; NMDA blockers; GABA A/B agonists; COX inhibitors; ii) ongoing developments in the pharmacology of spinal therapeutics focusing on less studied agents/targets (cholinesterase inhibition; Adenosine agonists; iii) novel intrathecal targeting methodologies including gene-based approaches (viral vectors, plasmids, interfering RNAs); antisense, and toxins (botulinum toxins; resniferatoxin, substance P Saporin); and iv) issues relevant to intrathecal drug delivery (neuraxial drug distribution), infusate delivery profile, drug dosing, formulation and principals involved in the preclinical evaluation of intrathecal drug safety.
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Affiliation(s)
- Tony L. Yaksh
- University of California, San Diego, Anesthesia Research Lab 0818, 9500 Gilman Dr. LaJolla, CA 92093, USA
| | - Casey J. Fisher
- University of California, San Diego, Anesthesia Research Lab 0818, 9500 Gilman Dr. LaJolla, CA 92093, USA
| | - Tyler M. Hockman
- University of California, San Diego, Anesthesia Research Lab 0818, 9500 Gilman Dr. LaJolla, CA 92093, USA
| | - Ashley J. Wiese
- University of California, San Diego, Anesthesia Research Lab 0818, 9500 Gilman Dr. LaJolla, CA 92093, USA
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Miller SL, Aroniadou-Anderjaska V, Pidoplichko VI, Figueiredo TH, Apland JP, Krishnan JKS, Braga MFM. The M1 Muscarinic Receptor Antagonist VU0255035 Delays the Development of Status Epilepticus after Organophosphate Exposure and Prevents Hyperexcitability in the Basolateral Amygdala. J Pharmacol Exp Ther 2016; 360:23-32. [PMID: 27799295 DOI: 10.1124/jpet.116.236125] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 10/27/2016] [Indexed: 12/31/2022] Open
Abstract
Exposure to organophosphorus toxins induces seizures that progress to status epilepticus (SE), which can cause brain damage or death. Seizures are generated by hyperstimulation of muscarinic receptors, subsequent to inhibition of acetylcholinesterase; this is followed by glutamatergic hyperactivity, which sustains and reinforces seizure activity. It has been unclear which muscarinic receptor subtypes are involved in seizure initiation and the development of SE in the early phases after exposure. Here, we show that pretreatment of rats with the selective M1 receptor antagonist, VU0255035 [N-(3-oxo-3-(4-(pyridine-4-yl)piperazin-1-yl)propyl)-benzo[c][1,2,5]thiadiazole-4 sulfonamide], significantly suppressed seizure severity and prevented the development of SE for about 40 minutes after exposure to paraoxon or soman, suggesting an important role of the M1 receptor in the early phases of seizure generation. In addition, in in vitro brain slices of the basolateral amygdala (a brain region that plays a key role in seizure initiation after nerve agent exposure), VU0255035 blocked the effects produced by bath application of paraoxon-namely, a brief barrage of spontaneous inhibitory postsynaptic currents, followed by a significant increase in the ratio of the total charge transferred by spontaneous excitatory postsynaptic currents over that of the inhibitory postsynaptic currents. Furthermore, paraoxon enhanced the hyperpolarization-activated cation current Ih in basolateral amygdala principal cells, which could be one of the mechanisms underlying the increased glutamatergic activity, an effect that was also blocked in the presence of VU0255035. Thus, selective M1 antagonists may be an efficacious pretreatment in contexts in which there is risk for exposure to organophosphates, as these antagonists will delay the development of SE long enough for medical assistance to arrive.
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Affiliation(s)
- Steven L Miller
- Departments of Anatomy, Physiology, and Genetics (S.L.M., V.A.-A., V.I.P., T.H.F., J.K.S.K., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), and Program in Neuroscience (S.L.M., V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neurotoxicology Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.)
| | - Vassiliki Aroniadou-Anderjaska
- Departments of Anatomy, Physiology, and Genetics (S.L.M., V.A.-A., V.I.P., T.H.F., J.K.S.K., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), and Program in Neuroscience (S.L.M., V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neurotoxicology Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.)
| | - Volodymyr I Pidoplichko
- Departments of Anatomy, Physiology, and Genetics (S.L.M., V.A.-A., V.I.P., T.H.F., J.K.S.K., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), and Program in Neuroscience (S.L.M., V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neurotoxicology Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.)
| | - Taiza H Figueiredo
- Departments of Anatomy, Physiology, and Genetics (S.L.M., V.A.-A., V.I.P., T.H.F., J.K.S.K., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), and Program in Neuroscience (S.L.M., V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neurotoxicology Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.)
| | - James P Apland
- Departments of Anatomy, Physiology, and Genetics (S.L.M., V.A.-A., V.I.P., T.H.F., J.K.S.K., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), and Program in Neuroscience (S.L.M., V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neurotoxicology Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.)
| | - Jishnu K S Krishnan
- Departments of Anatomy, Physiology, and Genetics (S.L.M., V.A.-A., V.I.P., T.H.F., J.K.S.K., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), and Program in Neuroscience (S.L.M., V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neurotoxicology Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.)
| | - Maria F M Braga
- Departments of Anatomy, Physiology, and Genetics (S.L.M., V.A.-A., V.I.P., T.H.F., J.K.S.K., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), and Program in Neuroscience (S.L.M., V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neurotoxicology Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.)
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36
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The distribution of muscarinic M1 receptors in the human hippocampus. J Chem Neuroanat 2016; 77:187-192. [PMID: 27435807 DOI: 10.1016/j.jchemneu.2016.07.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 07/13/2016] [Accepted: 07/15/2016] [Indexed: 11/21/2022]
Abstract
The muscarinic M1 receptor plays a significant role in cognition, probably by modulating information processing in key regions such as the hippocampus. To understand how the muscarinic M1 receptor achieves these functions in the hippocampus, it is critical to know the distribution of the receptor within this complex brain region. To date, there are limited data on the distribution of muscarinic M1 receptors in the human hippocampus which may also be confounded because some anti-muscarinic receptor antibodies have been shown to lack specificity. Initially, using Western blotting and immunohistochemistry, we showed the anti-muscarinic M1 receptor antibody to be used in our study bound to a single 62kDa protein that was absent in mice lacking the muscarinic M1 receptor gene. Then, using immunohistochemistry, we determined the distribution of muscarinic M1 receptors in human hippocampus from 10 subjects with no discernible history of a neurological or psychiatric disorder. Our data shows the muscarinic M1 receptor to be predominantly on pyramidal cells in the hippocampus. Muscarinic M1 receptor positive cells were most apparent in the deep polymorphic layer of the dentate gyrus, the pyramidal cell layer of cornu ammonis region 3, the cellular layers of the subiculum, layer II of the presubiculum and layer III and V of the parahippocampal gyrus. Positive cells were less numerous and less intensely stained in the pyramidal layer of cornu ammonis region 2 and were sparse in the molecular layer of the dentate gyrus as well as cornu ammonis region 1. Although immunoreactivity was present in the granular layer of the dentate gyrus, it was difficult to identity individual immunopositive cells, possibly due to the density of cells. This distribution of the muscarinic M1 receptors in human hippocampus, and its localisation on glutamatergic cells, would suggest the receptor has a significant role in modulating excitatory hippocampal neurotransmission.
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Zarnadze S, Bäuerle P, Santos-Torres J, Böhm C, Schmitz D, Geiger JR, Dugladze T, Gloveli T. Cell-specific synaptic plasticity induced by network oscillations. eLife 2016; 5. [PMID: 27218453 PMCID: PMC4929000 DOI: 10.7554/elife.14912] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 05/23/2016] [Indexed: 12/28/2022] Open
Abstract
Gamma rhythms are known to contribute to the process of memory encoding. However, little is known about the underlying mechanisms at the molecular, cellular and network levels. Using local field potential recording in awake behaving mice and concomitant field potential and whole-cell recordings in slice preparations we found that gamma rhythms lead to activity-dependent modification of hippocampal networks, including alterations in sharp wave-ripple complexes. Network plasticity, expressed as long-lasting increases in sharp wave-associated synaptic currents, exhibits enhanced excitatory synaptic strength in pyramidal cells that is induced postsynaptically and depends on metabotropic glutamate receptor-5 activation. In sharp contrast, alteration of inhibitory synaptic strength is independent of postsynaptic activation and less pronounced. Further, we found a cell type-specific, directionally biased synaptic plasticity of two major types of GABAergic cells, parvalbumin- and cholecystokinin-expressing interneurons. Thus, we propose that gamma frequency oscillations represent a network state that introduces long-lasting synaptic plasticity in a cell-specific manner. DOI:http://dx.doi.org/10.7554/eLife.14912.001 Changes in the strength of synapses – the connections between neurons – form the basis of learning and memory. This process, which is known as synaptic plasticity, incorporates transient experiences into persistent memory traces. However, a single synapse should not be viewed in isolation. Neurons typically belong to extensive networks made up of large numbers of cells, which show coordinated patterns of activity. The synchronized firing of the neurons in such a network is referred to as a network oscillation. The frequency of an oscillation – that is, the number of times per second that its component cells are active at the same time – reflects distinct physiological functions. For example, high frequency oscillations called gamma waves help new memories to form, but it is not clear exactly how they do this. By studying gamma oscillations in a brain region called the hippocampus, Zarnadze, Bäuerle et al. provide insights into the underlying mechanisms. Signals from “excitatory” neurons make the neuron on the other side of the synapse more likely to fire in response, and signals for “inhibitory” neurons make it less likely to fire. By recording the activity of excitatory neurons in mouse brain slices, Zarnadze, Bäuerle et al. show that gamma oscillations increase the strength of excitatory synapses in the hippocampus, allowing neurons to signal more easily across these connections. Blocking the activity of a protein called metabotropic glutamate receptor 5 prevents this increase in excitatory synaptic strength, suggesting that these receptors play an important role in memory processing. In contrast to excitatory neurons, gamma oscillations have different effects on two types of inhibitory neurons within the hippocampus. The oscillations increase the excitability of gamma-supporting inhibitory neurons, but at the same time reduce that of gamma-disturbing inhibitory neurons. These opposing changes in turn support synaptic plasticity. By showing that gamma oscillations contribute to changes in synaptic strength within the hippocampus, Zarnadze, Bäuerle et al. help to explain the importance of these rhythms for memory processing. Further research is now needed to fully decipher the roles of different cell types, and the synaptic connections between them, in the formation of new memories. DOI:http://dx.doi.org/10.7554/eLife.14912.002
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Affiliation(s)
- Shota Zarnadze
- Institute of Neurophysiology, Charité -Universitätsmedizin Berlin, Berlin, Germany
| | - Peter Bäuerle
- Institute of Neurophysiology, Charité -Universitätsmedizin Berlin, Berlin, Germany
| | - Julio Santos-Torres
- Institute of Neurophysiology, Charité -Universitätsmedizin Berlin, Berlin, Germany
| | - Claudia Böhm
- Neuroscience Research Center, Charité -Universitätsmedizin Berlin, Berlin, Germany
| | - Dietmar Schmitz
- Neuroscience Research Center, Charité -Universitätsmedizin Berlin, Berlin, Germany.,The NeuroCure Cluster of Excellence, Berlin, Germany.,Bernstein Center for Computational Neuroscience, Berlin, Germany
| | - Jörg Rp Geiger
- Institute of Neurophysiology, Charité -Universitätsmedizin Berlin, Berlin, Germany.,The NeuroCure Cluster of Excellence, Berlin, Germany
| | - Tamar Dugladze
- Institute of Neurophysiology, Charité -Universitätsmedizin Berlin, Berlin, Germany.,The NeuroCure Cluster of Excellence, Berlin, Germany
| | - Tengis Gloveli
- Institute of Neurophysiology, Charité -Universitätsmedizin Berlin, Berlin, Germany.,Bernstein Center for Computational Neuroscience, Berlin, Germany
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38
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Muscarinic acetylcholine receptor-mediated stimulation of retinal ganglion cell photoreceptors. Neuropharmacology 2016; 108:305-15. [PMID: 27055770 DOI: 10.1016/j.neuropharm.2016.04.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 04/01/2016] [Accepted: 04/01/2016] [Indexed: 12/16/2022]
Abstract
Melanopsin-dependent phototransduction in intrinsically photosensitive retinal ganglion cells (ipRGCs) involves a Gq-coupled phospholipase C (PLC) signaling cascade. Acetylcholine, released in the mammalian retina by starburst amacrine cells, can also activate Gq-PLC pathways through certain muscarinic acetylcholine receptors (mAChRs). Using multielectrode array recordings of rat retinas, we demonstrate that robust spiking responses can be evoked in neonatal and adult ipRGCs after bath application of the muscarinic agonist carbachol. The stimulatory action of carbachol on ipRGCs was a direct effect, as confirmed through calcium imaging experiments on isolated ipRGCs in purified cultures. Using flickering (6 Hz) yellow light stimuli at irradiances below the threshold for melanopsin activation, spiking responses could be elicited in ipRGCs that were suppressed by mAChR antagonism. Therefore, this work identified a novel melanopsin-independent pathway for stimulating sustained spiking in ganglion cell photoreceptors. This mAChR-mediated pathway could enhance ipRGC spiking responses in conditions known to evoke retinal acetylcholine release, such as those involving flickering or moving visual stimuli. Furthermore, this work identifies a pharmacological approach for light-independent ipRGC stimulation that could be targeted by mAChR agonists.
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Hopper S, Udawela M, Scarr E, Dean B. Allosteric modulation of cholinergic system: Potential approach to treating cognitive deficits of schizophrenia. World J Pharmacol 2016; 5:32-43. [DOI: 10.5497/wjp.v5.i1.32] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Revised: 11/26/2015] [Accepted: 01/04/2016] [Indexed: 02/06/2023] Open
Abstract
Schizophrenia is a psychiatric disorder affecting approximately 1% of the population worldwide and is characterised by the presence of positive and negative symptoms and cognitive deficits. Whilst current therapeutics ameliorate positive symptoms, they are largely ineffective in improving negative symptoms and cognitive deficits. The cholinergic neurotransmitter system heavily influences cognitive function and there is evidence that implicates disruption of the central cholinergic system in schizophrenia. Historically, targeting the cholinergic system has been impeded by poor selectivity leading to intolerable side effects warranting the need to develop more targeted therapeutic compounds. In this review we will summarise evidence supporting the roles of the cholinergic system, particularly the muscarinic M1 receptor, in the pathophysiology of schizophrenia and discuss the potential of a promising new class of candidate compounds, allosteric ligands, for addressing the difficulties involved in targeting this system. The body of evidence presented here highlights the dysfunction of the cholinergic system in schizophrenia and that targeting this system by taking advantage of allosteric ligands is having clinically meaningful effect on cognitive deficits.
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40
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Bjorefeldt A, Wasling P, Zetterberg H, Hanse E. Neuromodulation of fast-spiking and non-fast-spiking hippocampal CA1 interneurons by human cerebrospinal fluid. J Physiol 2016; 594:937-52. [PMID: 26634295 DOI: 10.1113/jp271553] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 11/30/2015] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS How the brain extracellular fluid influences the activity of GABAergic interneurons in vivo is not known. This issue is examined in the hippocampal brain slice by comparing GABAergic interneuron activity in human versus artificial cerebrospinal fluid. Human cerebrospinal fluid (hCSF) substantially increases the excitability of fast-spiking and non-fast-spiking CA1 interneurons. CA1 pyramidal cells are even more strongly excited by hCSF. The tonic excitation of pyramidal cells, in combination with an increased responsiveness of interneurons to excitatory input, is likely to promote the generation of synchronized network activity in the hippocampus. ABSTRACT GABAergic interneurons intricately regulate the activity of hippocampal and neocortical networks. Their function in vivo is likely to be tuned by neuromodulatory substances in the brain extracellular fluid. However, in vitro investigations of GABAergic interneuron function do not account for such effects, as neurons are kept in artificial extracellular fluid. To examine the neuromodulatory influence of brain extracellular fluid on GABAergic activity, we recorded from fast-spiking and non-fast-spiking CA1 interneurons, as well as from pyramidal cells, in the presence of human cerebrospinal fluid (hCSF), using a matched artificial cerebrospinal fluid (aCSF) as control. We found that hCSF increased the frequency of spontaneous firing more than twofold in the two groups of interneurons, and more than fourfold in CA1 pyramidal cells. hCSF did not affect the resting membrane potential of CA1 interneurons but caused depolarization in pyramidal cells. The increased excitability of interneurons and pyramidal cells was accompanied by reductions in after-hyperpolarization amplitudes and a left-shift in the frequency-current relationships. Our results suggest that ambient concentrations of neuromodulators in the brain extracellular fluid powerfully influence the excitability of neuronal networks.
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Affiliation(s)
- Andreas Bjorefeldt
- Department of Physiology, Institute of Neuroscience and Physiology, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Pontus Wasling
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, University of Gothenburg, 413 45 Gothenburg, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, 431 80 Molndal, Sweden.,Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Eric Hanse
- Department of Physiology, Institute of Neuroscience and Physiology, University of Gothenburg, 405 30 Gothenburg, Sweden
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Masuho I, Ostrovskaya O, Kramer GM, Jones CD, Xie K, Martemyanov KA. Distinct profiles of functional discrimination among G proteins determine the actions of G protein-coupled receptors. Sci Signal 2015; 8:ra123. [PMID: 26628681 DOI: 10.1126/scisignal.aab4068] [Citation(s) in RCA: 175] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Members of the heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptor (GPCR) family play key roles in many physiological functions and are extensively exploited pharmacologically to treat diseases. Many of the diverse effects of individual GPCRs on cellular physiology are transduced by heterotrimeric G proteins, which are composed of α, β, and γ subunits. GPCRs interact with and stimulate the binding of guanosine triphosphate (GTP) to the α subunit to initiate signaling. Mammalian genomes encode 16 different G protein α subunits, each one of which has distinct properties. We developed a single-platform, optical strategy to monitor G protein activation in live cells. With this system, we profiled the coupling ability of individual GPCRs for different α subunits, simultaneously quantifying the magnitude of the signal and the rates at which the receptors activated the G proteins. We found that individual receptors engaged multiple G proteins with varying efficacy and kinetics, generating fingerprint-like profiles. Different classes of GPCR ligands, including full and partial agonists, allosteric modulators, and antagonists, distinctly affected these fingerprints to functionally bias GPCR signaling. Finally, we showed that intracellular signaling modulators further altered the G protein-coupling profiles of GPCRs, which suggests that their differential abundance may alter signaling outcomes in a cell-specific manner. These observations suggest that the diversity of the effects of GPCRs on cellular physiology may be determined by their differential engagement of multiple G proteins, coupling to which produces signals with varying signal magnitudes and activation kinetics, properties that may be exploited pharmacologically.
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Affiliation(s)
- Ikuo Masuho
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA
| | - Olga Ostrovskaya
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA
| | - Grant M Kramer
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA. Harriet L. Wilkes Honors College, Florida Atlantic University, Jupiter, FL 33458, USA
| | - Christopher D Jones
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA. Harriet L. Wilkes Honors College, Florida Atlantic University, Jupiter, FL 33458, USA
| | - Keqiang Xie
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA
| | - Kirill A Martemyanov
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA.
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Kidd BA, Wroblewska A, Boland MR, Agudo J, Merad M, Tatonetti NP, Brown BD, Dudley JT. Mapping the effects of drugs on the immune system. Nat Biotechnol 2015; 34:47-54. [PMID: 26619012 PMCID: PMC4706827 DOI: 10.1038/nbt.3367] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2015] [Accepted: 08/11/2015] [Indexed: 11/18/2022]
Abstract
Understanding how drugs affect the immune system has consequences for treating disease and minimizing unwanted side effects. Here we present an integrative computational approach for predicting interactions between drugs and immune cells in a system-wide manner. The approach matches gene sets between transcriptional signatures to determine their similarity. We apply the method to model the interactions between 1,309 drugs and 221 immune cell types and predict 69,995 known and novel interactions. The resulting immune-cell pharmacology map is used to predict how 5 drugs influence 4 immune cell types in humans and mice. To validate the predictions, we analyzed patient records and examined cell population changes from in vivo experiments. Our method offers a tool for screening thousands of interactions to identify relationships between drugs and the immune system.
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Affiliation(s)
- Brian A Kidd
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Aleksandra Wroblewska
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Mary R Boland
- Department of Biomedical Informatics, Systems Biology and Medicine, Columbia University Medical Center, New York, New York, USA
| | - Judith Agudo
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Miriam Merad
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Nicholas P Tatonetti
- Department of Biomedical Informatics, Systems Biology and Medicine, Columbia University Medical Center, New York, New York, USA
| | - Brian D Brown
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Joel T Dudley
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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43
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Avella Gonzalez OJ, Mansvelder HD, van Pelt J, van Ooyen A. H-Channels Affect Frequency, Power and Amplitude Fluctuations of Neuronal Network Oscillations. Front Comput Neurosci 2015; 9:141. [PMID: 26635594 PMCID: PMC4652018 DOI: 10.3389/fncom.2015.00141] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 10/30/2015] [Indexed: 11/19/2022] Open
Abstract
Oscillations in network activity are ubiquitous in the brain and are involved in diverse cognitive functions. Oscillation characteristics, such as power, frequency, and temporal structure, depend on both network connectivity and intrinsic cellular properties, such as ion channel composition. An important class of channels, with key roles in regulating cell excitability, are h-channels. The h-current (Ih) is a slow, hyperpolarization-activated, depolarizing current that contributes to neuronal resonance and membrane potential. The impact of Ih on network oscillations, however, remains poorly understood. To elucidate the network effects of Ih, we used a computational model of a generic oscillatory neuronal network consisting of inhibitory and excitatory cells that were externally driven by excitatory action potentials and sustained depolarizing currents. We found that Ih increased the oscillation frequency and, in combination with external action potentials, representing input from areas outside the network, strongly decreased the synchrony of firing. As a consequence, the oscillation power and the duration of episodes during which the network exhibited high-amplitude oscillations were greatly reduced in the presence of Ih. Our results suggest that modulation of Ih or impaired expression of h-channels, as observed in epilepsy, could, by affecting oscillation dynamics, markedly alter network-level activity and potentially influence oscillation-dependent cognitive processes such as learning, memory and attention.
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Affiliation(s)
- Oscar J Avella Gonzalez
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam Amsterdam, Netherlands
| | - Huibert D Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam Amsterdam, Netherlands
| | - Jaap van Pelt
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam Amsterdam, Netherlands
| | - Arjen van Ooyen
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam Amsterdam, Netherlands
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44
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Dennis SH, Pasqui F, Colvin EM, Sanger H, Mogg AJ, Felder CC, Broad LM, Fitzjohn SM, Isaac JTR, Mellor JR. Activation of Muscarinic M1 Acetylcholine Receptors Induces Long-Term Potentiation in the Hippocampus. Cereb Cortex 2015; 26:414-26. [PMID: 26472558 PMCID: PMC4677984 DOI: 10.1093/cercor/bhv227] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Muscarinic M1 acetylcholine receptors (M1Rs) are highly expressed in the hippocampus, and their inhibition or ablation disrupts the encoding of spatial memory. It has been hypothesized that the principal mechanism by which M1Rs influence spatial memory is by the regulation of hippocampal synaptic plasticity. Here, we use a combination of recently developed, well characterized, selective M1R agonists and M1R knock-out mice to define the roles of M1Rs in the regulation of hippocampal neuronal and synaptic function. We confirm that M1R activation increases input resistance and depolarizes hippocampal CA1 pyramidal neurons and show that this profoundly increases excitatory postsynaptic potential-spike coupling. Consistent with a critical role for M1Rs in synaptic plasticity, we now show that M1R activation produces a robust potentiation of glutamatergic synaptic transmission onto CA1 pyramidal neurons that has all the hallmarks of long-term potentiation (LTP): The potentiation requires NMDA receptor activity and bi-directionally occludes with synaptically induced LTP. Thus, we describe synergistic mechanisms by which acetylcholine acting through M1Rs excites CA1 pyramidal neurons and induces LTP, to profoundly increase activation of CA1 pyramidal neurons. These features are predicted to make a major contribution to the pro-cognitive effects of cholinergic transmission in rodents and humans.
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Affiliation(s)
- Siobhan H Dennis
- Neuroscience, Eli Lilly & Company, Windlesham, Surrey GU20 6PH, UK
| | - Francesca Pasqui
- Neuroscience, Eli Lilly & Company, Windlesham, Surrey GU20 6PH, UK
| | - Ellen M Colvin
- Neuroscience, Eli Lilly & Company, Windlesham, Surrey GU20 6PH, UK
| | - Helen Sanger
- Neuroscience, Eli Lilly & Company, Windlesham, Surrey GU20 6PH, UK
| | - Adrian J Mogg
- Neuroscience, Eli Lilly & Company, Windlesham, Surrey GU20 6PH, UK
| | | | - Lisa M Broad
- Neuroscience, Eli Lilly & Company, Windlesham, Surrey GU20 6PH, UK
| | - Steve M Fitzjohn
- Neuroscience, Eli Lilly & Company, Windlesham, Surrey GU20 6PH, UK School of Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK
| | - John T R Isaac
- Neuroscience, Eli Lilly & Company, Windlesham, Surrey GU20 6PH, UK
| | - Jack R Mellor
- School of Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK
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45
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Rachakonda V, Jadeja RN, Urrunaga NH, Shah N, Ahmad D, Cheng K, Twaddell WS, Raufman JP, Khurana S. M1 Muscarinic Receptor Deficiency Attenuates Azoxymethane-Induced Chronic Liver Injury in Mice. Sci Rep 2015; 5:14110. [PMID: 26374068 PMCID: PMC4571652 DOI: 10.1038/srep14110] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 08/17/2015] [Indexed: 12/19/2022] Open
Abstract
Cholinergic nervous system regulates liver injury. However, the role of M1 muscarinic receptors (M1R) in modulating chronic liver injury is uncertain. To address this gap in knowledge we treated M1R-deficient and WT mice with azoxymethane (AOM) for six weeks and assessed liver injury responses 14 weeks after the last dose of AOM. Compared to AOM-treated WT mice, M1R-deficient mice had attenuated liver nodularity, fibrosis and ductular proliferation, α-SMA staining, and expression of α1 collagen, Tgfβ-R, Pdgf-R, Mmp-2, Timp-1 and Timp-2. In hepatocytes, these findings were associated with reductions of cleaved caspase-3 staining and Tnf-α expression. In response to AOM treatment, M1R-deficient mice mounted a vigorous anti-oxidant response by upregulating Gclc and Nqo1 expression, and attenuating peroxynitrite generation. M1R-deficient mouse livers had increased expression of Trail-R2, a promotor of stellate cell apoptosis; dual staining for TUNNEL and α-SMA revealed increased stellate cells apoptosis in livers from M1R-deficient mice compared to those from WT. Finally, pharmacological inhibition of M1R reduced H2O2-induced hepatocyte apoptosis in vitro. These results indicate that following liver injury, anti-oxidant response in M1R-deficient mice attenuates hepatocyte apoptosis and reduces stellate cell activation, thereby diminishing fibrosis. Therefore, targeting M1R expression and activation in chronic liver injury may provide therapeutic benefit.
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Affiliation(s)
- Vikrant Rachakonda
- Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, Maryland, 21201
| | - Ravirajsinh N Jadeja
- Section of Gastroenterology and Hepatology, Georgia Regents University, Augusta, GA 30912
| | - Nathalie H Urrunaga
- Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, Maryland, 21201
| | - Nirish Shah
- Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, Maryland, 21201
| | - Daniel Ahmad
- Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, Maryland, 21201
| | - Kunrong Cheng
- Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, Maryland, 21201
| | - William S Twaddell
- Department of Pathology, University of Maryland School of Medicine, Baltimore, Maryland, 21201
| | - Jean-Pierre Raufman
- Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, Maryland, 21201
| | - Sandeep Khurana
- Section of Gastroenterology and Hepatology, Georgia Regents University, Augusta, GA 30912
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46
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Kurowski P, Gawlak M, Szulczyk P. Muscarinic receptor control of pyramidal neuron membrane potential in the medial prefrontal cortex (mPFC) in rats. Neuroscience 2015; 303:474-88. [PMID: 26186898 DOI: 10.1016/j.neuroscience.2015.07.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 07/08/2015] [Indexed: 11/19/2022]
Abstract
Damage to the cholinergic input to the prefrontal cortex has been implicated in neuropsychiatric disorders. Cholinergic endings release acetylcholine, which activates nicotinic and/or G-protein-coupled muscarinic receptors. Muscarinic receptors activate transduction systems, which control cellular effectors that regulate the membrane potential in medial prefrontal cortex (mPFC) neurons. The mechanisms responsible for the cholinergic-dependent depolarization of mPFC layer V pyramidal neurons in slices obtained from young rats were elucidated in this study. Glutamatergic and GABAergic transmission as well as tetrodotoxin (TTX)-sensitive Na(+) and voltage-dependent Ca(++) currents were eliminated. Cholinergic receptor stimulation by carbamoylcholine chloride (CCh; 100 μM) evoked depolarization (10.0 ± 1.3 mV), which was blocked by M1/M4 (pirenzepine dihydrochloride, 2 μM) and M1 (VU 0255035, 5 μM) muscarinic receptor antagonists and was not affected by a nicotinic receptor antagonist (mecamylamine hydrochloride, 10 μM). CCh-dependent depolarization was attenuated by extra- (20 μM) or intracellular (50 μM) application of an inhibitor of the βγ-subunit-dependent transduction system (gallein). It was also inhibited by intracellular application of a βγ-subunit-binding peptide (GRK2i, 10μM). mPFC pyramidal neurons express Nav1.9 channels. CCh-dependent depolarization was abolished in the presence of antibodies against Nav1.9 channels in the intracellular solution and augmented by the presence of ProTx-I toxin (100 nM) in the extracellular solution. CCh-induced depolarization was not affected by the following reagents: intracellular transduction system blockers, including U-73122 (10 μM), chelerythrine chloride (5 μM), SQ 22536 (100 μM) and H-89 (2 μM); channel blockers, including Ba(++) ions (200 μM), apamin (100 nM), flufenamic acid (200 μM), 2-APB (200 μM), SKF 96365 (50 μM), and ZD 7288 (50 μM); and a Na(+)/Ca(++) exchanger blocker, benzamil (20 μM). We conclude that muscarinic M1 receptor-dependent depolarization in mPFC pyramidal neurons is evoked by the activation of Nav1.9 channels and that the signal transduction pathway involves G-protein βγ subunits.
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Affiliation(s)
- P Kurowski
- Laboratory of Physiology and Pathophysiology, Centre for Preclinical Research and Technology, The Medical University of Warsaw, Banacha 1B, Warsaw 02-097, Poland
| | - M Gawlak
- Laboratory of Physiology and Pathophysiology, Centre for Preclinical Research and Technology, The Medical University of Warsaw, Banacha 1B, Warsaw 02-097, Poland
| | - P Szulczyk
- Laboratory of Physiology and Pathophysiology, Centre for Preclinical Research and Technology, The Medical University of Warsaw, Banacha 1B, Warsaw 02-097, Poland.
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47
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Hainke S, Wildmann J, Del Rey A. Deletion of muscarinic type 1 acetylcholine receptors alters splenic lymphocyte functions and splenic noradrenaline concentration. Int Immunopharmacol 2015; 29:135-42. [PMID: 26002586 DOI: 10.1016/j.intimp.2015.05.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 04/26/2015] [Accepted: 05/07/2015] [Indexed: 11/18/2022]
Abstract
The existence of interactions between the immune and the sympathetic nervous systems is well established. Noradrenaline can promote or inhibit the immune response, and conversely, the immune response itself can affect noradrenaline concentration in lymphoid organs, such as the spleen. It is also well known that acetylcholine released by pre-ganglionic neurons can modulate noradrenaline release by the postsynaptic neuron. The spleen does not receive cholinergic innervation, but it has been reported that lymphocytes themselves can produce acetylcholine, and express acetylcholine receptors and acetylcholinesterase. We found that the spleen of not overtly immunized mice in which muscarinic type 1 acetylcholine receptors have been knocked out (M1KO) has higher noradrenaline concentrations than that of the wildtype mice, without comparable alterations in the heart, in parallel to a decreased number of IgG-producing B cells. Splenic lymphocytes from M1KO mice displayed increased in vitro-induced cytotoxicity, and this was observed only when CD4(+) T cells were present. In contrast, heterozygous acetylcholinesterase (AChE+/-) mice, had no alterations in splenic noradrenaline concentration, but the in vitro proliferation of AChE+/- CD4(+) T cells was increased. It is theoretically conceivable that reciprocal effects between neuronally and non-neuronally derived acetylcholine and noradrenaline might contribute to the results reported. Our results emphasize the need to consider the balance between the effects of these mediators for the final immunoregulatory outcome.
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Affiliation(s)
- Susanne Hainke
- Research Group Immunophysiology, Division of Neurophysiology, Inst. of Physiology and Pathophysiology, Deutschhausstrasse 2, 35037 Marburg, Germany
| | - Johannes Wildmann
- Research Group Immunophysiology, Division of Neurophysiology, Inst. of Physiology and Pathophysiology, Deutschhausstrasse 2, 35037 Marburg, Germany
| | - Adriana Del Rey
- Research Group Immunophysiology, Division of Neurophysiology, Inst. of Physiology and Pathophysiology, Deutschhausstrasse 2, 35037 Marburg, Germany.
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48
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Schneider J, Lewen A, Ta TT, Galow LV, Isola R, Papageorgiou IE, Kann O. A reliable model for gamma oscillations in hippocampal tissue. J Neurosci Res 2015; 93:1067-78. [PMID: 25808046 DOI: 10.1002/jnr.23590] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 02/16/2015] [Accepted: 02/27/2015] [Indexed: 12/13/2022]
Abstract
Gamma oscillations (30-100 Hz) reflect a fast brain rhythm that provides a fundamental mechanism of complex neuronal information processing in the hippocampus and in the neocortex in vivo. Gamma oscillations have been implicated in higher brain functions, such as sensory perception, motor activity, and memory formation. Experimental studies on synaptic transmission and bioenergetics underlying gamma oscillations have primarily used acute slices of the hippocampus. This study tests whether organotypic hippocampal slice cultures of the rat provide an alternative model for cortical gamma oscillations in vitro. Our findings are that 1) slice cultures feature well-preserved laminated architecture and neuronal morphology; 2) slice cultures of different maturation stages (7-28 days in vitro) reliably express gamma oscillations at about 40 Hz as induced by cholinergic (acetylcholine) or glutamatergic (kainate) receptor agonists; 3) the peak frequency of gamma oscillations depends on the temperature, with an increase of ∼ 3.5 Hz per degree Celsius for the range of 28-36 °C; 4) most slice cultures show persistent gamma oscillations for ∼ 1 hr during electrophysiological local field potential recordings, and later alterations may occur; and 5) in slice cultures, glucose at a concentration of 5 mM in the recording solution is sufficient to power gamma oscillations, and additional energy substrate supply with monocarboxylate metabolite lactate (2 mM) exclusively increases the peak frequency by ∼ 4 Hz. This study shows that organotypic hippocampal slice cultures provide a reliable model to study agonist-induced gamma oscillations at glucose levels near the physiological range.
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Affiliation(s)
- Justus Schneider
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Andrea Lewen
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Thuy-Truc Ta
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Lukas V Galow
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Raffaella Isola
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Ismini E Papageorgiou
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Oliver Kann
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
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49
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Effect of the M1 Muscarinic Acetylcholine Receptor on Retinal Neuron Number Studied with Gene-Targeted Mice. J Mol Neurosci 2015; 56:472-9. [PMID: 25720339 DOI: 10.1007/s12031-015-0524-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Accepted: 02/11/2015] [Indexed: 01/04/2023]
Abstract
Pharmacological activation of the M1 muscarinic receptor subtype was suggested to promote the survival of retinal neurons. We examined the hypothesis that the M1 receptor is crucial for retinal neuron survival in vivo by using mice devoid of the M1 receptor gene. Muscarinic receptor gene expression was determined in the retina using real-time PCR. The amount of neurons in the retinal ganglion cell layer and of axons in the optic nerve was determined in retinal wholemounts stained with cresyl blue and in optic nerve cross-sections stained with toluidine blue, respectively. mRNA of all five muscarinic receptor subtypes (M1-M5) was detected in the retina from wild-type mice. Remarkably, M2 and M3 receptor mRNA were most abundant. In retinas from M1 receptor-deficient mice, M4 receptor mRNA expression was increased compared to that of wild-type mice, while no marked changes in the mRNA expression levels of the other muscarinic receptor subtypes were observed. The amount of cells in the retinal ganglion cell layer and the amount of axons in the optic nerve did not differ between M1 receptor-deficient and wild-type mice. The present findings suggest that the M1 receptor is not essential for the survival of retinal neurons in vivo.
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50
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Lawrence JJ, Haario H, Stone EF. Presynaptic cholinergic neuromodulation alters the temporal dynamics of short-term depression at parvalbumin-positive basket cell synapses from juvenile CA1 mouse hippocampus. J Neurophysiol 2015; 113:2408-19. [PMID: 25632072 DOI: 10.1152/jn.00167.2014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 01/21/2015] [Indexed: 11/22/2022] Open
Abstract
Parvalbumin-positive basket cells (PV BCs) of the CA1 hippocampus are active participants in theta (5-12 Hz) and gamma (20-80 Hz) oscillations in vivo. When PV BCs are driven at these frequencies in vitro, inhibitory postsynaptic currents (IPSCs) in synaptically connected CA1 pyramidal cells exhibit paired-pulse depression (PPD) and multiple-pulse depression (MPD). Moreover, PV BCs express presynaptic muscarinic acetylcholine receptors (mAChRs) that may be activated by synaptically released acetylcholine during learning behaviors in vivo. Using acute hippocampal slices from the CA1 hippocampus of juvenile PV-GFP mice, we performed whole cell recordings from synaptically connected PV BC-CA1 pyramidal cell pairs to investigate how bath application of 10 μM muscarine impacts PPD and MPD at CA1 PV BC-pyramidal cell synapses. In accordance with previous studies, PPD and MPD magnitude increased with stimulation frequency. mAChR activation reduced IPSC amplitude and transiently reduced PPD, but MPD was largely maintained. Consistent with a reduction in release probability (pr), MPD and mAChR activation increased both the coefficient of variation of IPSC amplitudes and the fraction of failures. Using variance-mean analysis, we converted MPD trains to pr functions and developed a kinetic model that optimally fit six distinct pr conditions. The model revealed that vesicular depletion caused MPD and that recovery from depression was dependent on calcium. mAChR activation reduced the presynaptic calcium transient fourfold and initial pr twofold, thereby reducing PPD. However, mAChR activation slowed calcium-dependent recovery from depression during sustained repetitive activity, thereby preserving MPD. Thus the activation of presynaptic mAChRs optimally protects PV BCs from vesicular depletion during short bursts of high-frequency activity.
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Affiliation(s)
- J Josh Lawrence
- Center for Structural and Functional Neuroscience, University of Montana, Missoula, Montana; Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, Montana;
| | - Heikki Haario
- Department of Mathematics and Physics, Lappeenranta University of Technology, Lappeenranta, Finland
| | - Emily F Stone
- Center for Structural and Functional Neuroscience, University of Montana, Missoula, Montana; Department of Mathematical Sciences, University of Montana, Missoula, Montana; and
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