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Costas-Ferreira C, Durán R, Faro LRF. Evaluation of the potential role of glutamatergic, cholinergic, and nitrergic systems in the dopamine release induced by the pesticide glyphosate in rat striatum. J Appl Toxicol 2024. [PMID: 38828527 DOI: 10.1002/jat.4651] [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: 12/29/2023] [Revised: 05/14/2024] [Accepted: 05/20/2024] [Indexed: 06/05/2024]
Abstract
Glyphosate (GLY) is a pesticide that severely alters nigrostriatal dopaminergic neurotransmission, inducing great increases in dopamine release from rat dorsal striatum. This GLY-induced striatal dopamine overflow occurs through mechanisms not yet fully understood, hence the interest in evaluating the role of other neurotransmitter systems in such effects. So, the main objective of this mechanistic study was to evaluate the possible mediation of the glutamatergic, cholinergic, and nitrergic systems in the GLY-induced in vivo dopamine release from rat dorsal striatum. The extracellular dopamine levels were measured by cerebral microdialysis and HPLC with electrochemical detection. Intrastriatal administration of GLY (5 mmol/L) significantly increased the dopamine release (1102%). Pretreatment with MK-801 (50 or 400 μmol/L), a non-competitive antagonist of NMDA receptors, significantly decreased the effect of GLY (by 70% and 74%, respectively), whereas AP-5 (400 μmol/L), a competitive antagonist of NMDA receptors, or CNQX (500 μmol/L), an AMPA/kainate receptor antagonist, had no significant effect. Administration of the nitric oxide synthase inhibitors, L-nitroarginine (L-NAME, 100 μmol/L) or 7-nitroindazole (7-NI, 100 μmol/L), also did not alter the effect of GLY on dopamine release. Finally, pretreatment of the animals with mecamylamine, an antagonist of nicotinic receptors, decreased the effect of GLY on dopamine release by 49%, whereas atropine, a muscarinic antagonist, had no significant effect. These results indicate that GLY-induced dopamine release largely depends on the activation of NMDA and nicotinic receptors in rat dorsal striatum. Future research is needed to determine the effects of this pesticide at environmentally relevant concentrations.
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Affiliation(s)
- Carmen Costas-Ferreira
- Department of Functional Biology and Health Sciences, Faculty of Biology, University of Vigo, Vigo, Spain
| | - Rafael Durán
- Department of Functional Biology and Health Sciences, Faculty of Biology, University of Vigo, Vigo, Spain
| | - Lilian R F Faro
- Department of Functional Biology and Health Sciences, Faculty of Biology, University of Vigo, Vigo, Spain
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2
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Abdelnaim MA, Lang-Hambauer V, Hebel T, Schoisswohl S, Schecklmann M, Deuter D, Schlaier J, Langguth B. Deep brain stimulation for treatment resistant obsessive compulsive disorder; an observational study with ten patients under real-life conditions. Front Psychiatry 2023; 14:1242566. [PMID: 37779611 PMCID: PMC10533930 DOI: 10.3389/fpsyt.2023.1242566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 08/23/2023] [Indexed: 10/03/2023] Open
Abstract
Introduction Obsessive-compulsive disorder (OCD) affects 2-3% of the global population, causing distress in many functioning levels. Standard treatments only lead to a partial recovery, and about 10% of the patients remain treatment-resistant. Deep brain stimulation offers a treatment option for severe, therapy-refractory OCD, with a reported response of about 60%. We report a comprehensive clinical, demographic, and treatment data for patients who were treated with DBS in our institution. Methods We offered DBS to patients with severe chronic treatment resistant OCD. Severity was defined as marked impairment in functioning and treatment resistance was defined as non-response to adequate trials of medications and psychotherapy. Between 2020 and 2022, 11 patients were implanted bilaterally in the bed nucleus of stria terminalis (BNST). Patients were evaluated with YBOCS, MADRS, GAF, CGI, and WHOQOL-BREF. We performed the ratings at baseline (before surgery), after implantation before the start of the stimulation, after reaching satisfactory stimulation parameters, and at follow-up visits 3, 6, 9, and 12 months after optimized stimulation. Results One patient has retracted his consent to publish the results of his treatment, thus we are reporting the results of 10 patients (5 males, 5 females, mean age: 37 years). Out of our 10 patients, 6 have shown a clear response indicated by a YBOCS-reduction between 42 and 100 percent at last follow-up. One further patient experienced a subjectively dramatic effect on OCD symptoms, but opted afterwards to stop the stimulation. The other 3 patients showed a slight, non-significant improvement of YBOCS between 8.8 and 21.9%. The overall mean YBOCS decreased from 28.3 at baseline to 13.3 (53% reduction) at the last follow-up. The improvement of the OCD symptoms was also accompanied by an improvement of depressive symptoms, global functioning, and quality of life. Conclusion Our results suggest that BNST-DBS can be effective for treatment-resistant OCD patients, as indicated by a reduction in symptoms and an overall improvement in functioning. Despite the need for additional research to define the patients' selection criteria, the most appropriate anatomical target, and the most effective stimulation parameters, improved patient access for this therapy should be established.
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Affiliation(s)
- Mohamed A. Abdelnaim
- Department of Psychiatry and Psychotherapy, University Regensburg, Regensburg, Germany
- Center for Deep Brain Stimulation, University Regensburg, Regensburg, Germany
| | - Verena Lang-Hambauer
- Department of Psychiatry and Psychotherapy, University Regensburg, Regensburg, Germany
- Center for Deep Brain Stimulation, University Regensburg, Regensburg, Germany
| | - Tobias Hebel
- Department of Psychiatry and Psychotherapy, University Regensburg, Regensburg, Germany
| | - Stefan Schoisswohl
- Department of Psychiatry and Psychotherapy, University Regensburg, Regensburg, Germany
- Department of Psychology, University of the Bundeswehr Munich, Neubiberg, Germany
| | - Martin Schecklmann
- Department of Psychiatry and Psychotherapy, University Regensburg, Regensburg, Germany
| | - Daniel Deuter
- Center for Deep Brain Stimulation, University Regensburg, Regensburg, Germany
- Department of Neurosurgery, University Regensburg, Regensburg, Germany
| | - Juergen Schlaier
- Center for Deep Brain Stimulation, University Regensburg, Regensburg, Germany
- Department of Neurosurgery, University Regensburg, Regensburg, Germany
| | - Berthold Langguth
- Department of Psychiatry and Psychotherapy, University Regensburg, Regensburg, Germany
- Center for Deep Brain Stimulation, University Regensburg, Regensburg, Germany
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3
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Ren P, Ding W, Li S, Liu G, Luo M, Zhou W, Cheng R, Li Y, Wang P, Li Z, Yao L, Jiang Q, Liang X. Regional transcriptional vulnerability to basal forebrain functional dysconnectivity in mild cognitive impairment patients. Neurobiol Dis 2023; 177:105983. [PMID: 36586468 DOI: 10.1016/j.nbd.2022.105983] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 12/07/2022] [Accepted: 12/28/2022] [Indexed: 12/30/2022] Open
Abstract
Nucleus basalis of Meynert (NbM), one of the earliest targets of Alzheimer's disease (AD), may act as a seed for pathological spreading to its connected regions. However, the underlying basis of regional vulnerability to NbM dysconnectivity remains unclear. NbM functional dysconnectivity was assessed using resting-state fMRI data of health controls and mild cognitive impairment (MCI) patients from the Alzheimer's disease Neuroimaging Initiative (ADNI2/GO phase). Transcriptional correlates of NbM dysconnectivity was explored by leveraging public intrinsic and differential post-mortem brain-wide gene expression datasets from Allen Human Brain Atlas (AHBA) and Mount Sinai Brain Bank (MSBB). By constructing an individual-level tissue-specific gene set risk score (TGRS), we evaluated the contribution of NbM dysconnectivity-correlated gene sets to change rate of cerebral spinal fluid (CSF) biomarkers during preclinical stage of AD, as well as to MCI onset age. An independent cohort of health controls and MCI patients from ADNI3 was used to validate our main findings. Between-group comparison revealed significant connectivity reduction between the right NbM and right middle temporal gyrus in MCI. This regional vulnerability to NbM dysconnectivity correlated with intrinsic expression of genes enriched in protein and immune functions, as well as with differential expression of genes enriched in cholinergic receptors, immune, vascular and energy metabolism functions. TGRS of these NbM dysconnectivity-correlated gene sets are associated with longitudinal amyloid-beta change at preclinical stages of AD, and contributed to MCI onset age independent of traditional AD risks. Our findings revealed the transcriptional vulnerability to NbM dysconnectivity and their crucial role in explaining preclinical amyloid-beta change and MCI onset age, which offer new insights into the early AD pathology and encourage more investigation and clinical trials targeting NbM.
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Affiliation(s)
- Peng Ren
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China; Laboratory for Space Environment and Physical Science, Harbin Institute of Technology, Harbin 150001, China
| | - Wencai Ding
- Department of Neurology, First Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Siyang Li
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China; Laboratory for Space Environment and Physical Science, Harbin Institute of Technology, Harbin 150001, China
| | - Guiyou Liu
- Beijing Institute for Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing 100069, China; Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Meng Luo
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Wenyang Zhou
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Rui Cheng
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Yiqun Li
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Pingping Wang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Zhipeng Li
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China; Laboratory for Space Environment and Physical Science, Harbin Institute of Technology, Harbin 150001, China
| | - Lifen Yao
- Department of Neurology, First Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Qinghua Jiang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China; Key Laboratory of Biological Big Data (Harbin Institute of Technology), Ministry of Education, Harbin 150001, China.
| | - Xia Liang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China; Laboratory for Space Environment and Physical Science, Harbin Institute of Technology, Harbin 150001, China.
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Pilc A, Machaczka A, Kawalec P, Smith JL, Witkin JM. Where do we go next in antidepressant drug discovery? A new generation of antidepressants: a pivotal role of AMPA receptor potentiation and mGlu2/3 receptor antagonism. Expert Opin Drug Discov 2022; 17:1131-1146. [PMID: 35934973 DOI: 10.1080/17460441.2022.2111415] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
INTRODUCTION Major depressive disorder remains a prevalent world-wide health problem. Currently available antidepressant medications take weeks of dosing, do not produce antidepressant response in all patients, and have undesirable ancillary effects. AREAS COVERED The present opinion piece focuses on the major inroads to the creation of new antidepressants. These include N-methyl-D-aspartate (NMDA) receptor antagonists and related compounds like ketamine, psychedelic drugs like psilocybin, and muscarinic receptor antagonists like scopolamine. The preclinical and clinical pharmacological profile of these new-age antidepressant drugs is discussed. EXPERT OPINION Preclinical and clinical data have accumulated to predict a next generation of antidepressant medicines. In contrast to the current standard of care antidepressant drugs, these compounds differ in that they demonstrate rapid activity, often after a single dose, and effects that outlive their presence in brain. These compounds also can provide efficacy for treatment-resistant depressed patients. The mechanism of action of these compounds suggests a strong glutamatergic component that involves the facilitation of AMPA receptor function. Antagonism of mGlu2/3 receptors is also relevant to the antidepressant pharmacology of this new class of drugs. Based upon the ongoing efforts to develop these new-age antidepressants, new drug approvals are predicted in the near future.
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Affiliation(s)
- Andrzej Pilc
- Department of Neurobiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland.,Drug Management Department, Institute of Public Health, Faculty of Health Sciences, Jagiellonian University, Krakow, Poland
| | - Agata Machaczka
- Department of Neurobiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Paweł Kawalec
- Drug Management Department, Institute of Public Health, Faculty of Health Sciences, Jagiellonian University, Krakow, Poland
| | - Jodi L Smith
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN, USA
| | - Jeffrey M Witkin
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN, USA
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Cover KK, Mathur BN. Axo-axonic synapses: Diversity in neural circuit function. J Comp Neurol 2021; 529:2391-2401. [PMID: 33314077 PMCID: PMC8053672 DOI: 10.1002/cne.25087] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 12/04/2020] [Accepted: 12/07/2020] [Indexed: 12/20/2022]
Abstract
The chemical synapse is the principal form of contact between neurons of the central nervous system. These synapses are typically configured as presynaptic axon terminations onto postsynaptic dendrites or somata, giving rise to axo-dendritic and axo-somatic synapses, respectively. Beyond these common synapse configurations are less-studied, non-canonical synapse types that are prevalent throughout the brain and significantly contribute to neural circuit function. Among these are the axo-axonic synapses, which consist of an axon terminating on another axon or axon terminal. Here, we review evidence for axo-axonic synapse contributions to neural signaling in the mammalian nervous system and survey functional neural circuit motifs enabled by these synapses. We also detail how recent advances in microscopy, transgenics, and biological sensors may be used to identify and functionally assay axo-axonic synapses.
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Affiliation(s)
- Kara K. Cover
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD USA 21201
| | - Brian N. Mathur
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD USA 21201
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Nersisyan S, Bekisz M, Kublik E, Granseth B, Wróbel A. Cholinergic and Noradrenergic Modulation of Corticothalamic Synaptic Input From Layer 6 to the Posteromedial Thalamic Nucleus in the Rat. Front Neural Circuits 2021; 15:624381. [PMID: 33981204 PMCID: PMC8107268 DOI: 10.3389/fncir.2021.624381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 03/22/2021] [Indexed: 11/13/2022] Open
Abstract
Cholinergic and noradrenergic neuromodulation of the synaptic transmission from cortical layer 6 of the primary somatosensory cortex to neurons in the posteromedial thalamic nucleus (PoM) was studied using an in vitro slice preparation from young rats. Cholinergic agonist carbachol substantially decreased the amplitudes of consecutive excitatory postsynaptic potentials (EPSPs) evoked by a 20 Hz five pulse train. The decreased amplitude effect was counteracted by a parallel increase of synaptic frequency-dependent facilitation. We found this modulation to be mediated by muscarinic acetylcholine receptors. In the presence of carbachol the amplitudes of the postsynaptic potentials showed a higher trial-to-trial coefficient of variation (CV), which suggested a presynaptic site of action for the modulation. To substantiate this finding, we measured the failure rate of the excitatory postsynaptic currents in PoM cells evoked by “pseudominimal” stimulation of corticothalamic input. A higher failure-rate in the presence of carbachol indicated decreased probability of transmitter release at the synapse. Activation of the noradrenergic modulatory system that was mimicked by application of norepinephrine did not affect the amplitude of the first EPSP evoked in the five-pulse train, but later EPSPs were diminished. This indicated a decrease of the synaptic frequency-dependent facilitation. Treatment with noradrenergic α-2 agonist clonidine, α-1 agonist phenylephrine, or β-receptor agonist isoproterenol showed that the modulation may partly rely on α-2 adrenergic receptors. CV analysis did not suggest a presynaptic action of norepinephrine. We conclude that cholinergic and noradrenergic modulation act as different variable dynamic controls for the corticothalamic mechanism of the frequency-dependent facilitation in PoM.
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Affiliation(s)
- Syune Nersisyan
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.,Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Marek Bekisz
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Ewa Kublik
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Björn Granseth
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Andrzej Wróbel
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.,Faculty of Philosophy, University of Warsaw, Warsaw, Poland
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Beyeler A, Dabrowska J. Neuronal diversity of the amygdala and the bed nucleus of the stria terminalis. HANDBOOK OF BEHAVIORAL NEUROSCIENCE 2020; 26:63-100. [PMID: 32792868 DOI: 10.1016/b978-0-12-815134-1.00003-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Anna Beyeler
- Neurocentre Magendie, French National Institutes of Health (INSERM) unit 1215, Neurocampus of Bordeaux University, Bordeaux, France
| | - Joanna Dabrowska
- Center for the Neurobiology of Stress Resilience and Psychiatric Disorders, Discipline of Cellular and Molecular Pharmacology, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
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8
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Di T, Wang Y, Zhang Y, Sha S, Zeng Y, Chen L. Dopaminergic afferents from midbrain to dorsolateral bed nucleus of stria terminalis inhibit release and expression of corticotropin-releasing hormone in paraventricular nucleus. J Neurochem 2020; 154:218-234. [PMID: 32096869 DOI: 10.1111/jnc.14992] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 02/07/2020] [Accepted: 02/21/2020] [Indexed: 01/21/2023]
Abstract
Dopaminergic (DAergic) neurons of the midbrain ventral tegmental area (VTA) are known to regulate the hypothalamic-pituitary-adrenal (HPA) axis but have no direct projections to the paraventricular nucleus (PVN) of the hypothalamus. This study investigated whether VTA DAergic afferents modulate glutamatergic transmission-dependent GABAergic neurons in dorsolateral bed nucleus of stria terminalis (dlBNST) to affect the activity of the HPA-axis. Herein, we demonstrate that systemic administration of the neurotoxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or the VTA-injection of 1-methyl-4-phenylpyridinium ion (MPP+) in male mice (MPTP-mice and MPP+mice) caused a decline of tyrosine hydroxylase positive (TH+) cells in VTA with a reduction in TH+fibers in the dlBNST. MPTP-mice and MPP+mice displayed a clear increase in serum levels of corticosterone (CORT) and adrenocorticotropic hormone, corticotropin-releasing hormone (CRH) expression, and CRH neuron activity in PVN. The presynaptic glutamate release, glutamatergic synaptic transmission and induction of long-term potentiation in dlBNST of MPTP-mice were suppressed, and these effects were rescued by a D1-like DAergic receptor (D1R) agonist and mimicked in control dlBNST by blockade of D1R. MPTP-mice exhibited low expression of glutamic acid decarboxylase and dysfunction of the excitatory-dependent GABAergic circuit in dlBNST, and these effects were recovered by the administration of D1R agonist. Furthermore, either dlBNST-injection of D1R agonist or PVN-injection of GABAA receptor (GABAA R) agonist could correct the increased secretion and expression of CRH in MPTP-mice. The results indicate that the DAergic afferents from VTA enhance excitatory-dependent activation of GABAergic neurons in dlBNST, which suppress the activity of the HPA-axis.
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Affiliation(s)
- Tingting Di
- State Key Lab of Reproductive Medicine, Nanjing Medical University, Nanjing, China.,Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Ya Wang
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Yajie Zhang
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Sha Sha
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Yanying Zeng
- Department of Gerontology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ling Chen
- State Key Lab of Reproductive Medicine, Nanjing Medical University, Nanjing, China.,Department of Physiology, Nanjing Medical University, Nanjing, China
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9
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Kaur S, DasGupta G, Singh S. Altered Neurochemistry in Alzheimer’s Disease: Targeting Neurotransmitter Receptor Mechanisms and Therapeutic Strategy. NEUROPHYSIOLOGY+ 2019. [DOI: 10.1007/s11062-019-09823-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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10
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Smail MA, Soles JL, Karwoski TE, Rubin RT, Rhodes ME. Sexually diergic hypothalamic-pituitary-adrenal axis responses to selective and non-selective muscarinic antagonists prior to cholinergic stimulation by physostigmine in rats. Brain Res Bull 2017; 137:23-34. [PMID: 29122691 DOI: 10.1016/j.brainresbull.2017.11.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 10/21/2017] [Accepted: 11/02/2017] [Indexed: 01/02/2023]
Abstract
Central cholinergic systems regulate the hypothalamic-pituitary-adrenal (HPA) axis differentially in males and females (sexual diergism). We previously investigated the role of muscarinic receptors in this regulation by administering physostigmine (PHYSO), an acetylcholinesterase inhibitor, to male and female rats pretreated with scopolamine (SCOP), a nonselective muscarinic antagonist. SCOP pretreatment enhanced adrenocorticotropic hormone (ACTH) and corticosterone (CORT) responses in both sexes, but males had greater ACTH responses while females had greater CORT responses. In the present study, we further explored the role of muscarinic receptor subtypes in HPA axis regulation by administering PHYSO to male and female rats following SCOP or various doses of either the M1 or the M2 selective muscarinic receptor antagonists, pirenzepine (PIREN) or methoctramine (METHO). Blood was sampled before and at multiple times after PHYSO. ACTH and CORT were determined by highly specific immunoassays. M1 antagonism by PIREN prior to PHYSO resulted in sustained, dose-dependent increases in ACTH and CORT: ACTH responses were similar in both sexes, and CORT responses were greater in females. M2 antagonism by METHO prior to PHYSO resulted in overall decreases in ACTH and CORT: ACTH and CORT responses were higher in females but lower in both sexes than the hormone responses following PIREN or SCOP pretreatment. Area under the curve analyses supported these findings. These results suggest that specific muscarinic receptor subtypes differentially influence the HPA axis in a sexually diergic manner.
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Affiliation(s)
- Marissa A Smail
- Department of Biology, Saint Vincent College, Latrobe, PA, United States
| | - Jessica L Soles
- Department of Biology, Saint Vincent College, Latrobe, PA, United States
| | - Tracy E Karwoski
- Center for Neurosciences Research, Allegheny General Hospital, Pittsburgh, PA, United States
| | - Robert T Rubin
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
| | - Michael E Rhodes
- Department of Biology, Saint Vincent College, Latrobe, PA, United States.
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11
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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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12
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Guo JD, O'Flaherty BM, Rainnie DG. Serotonin gating of cortical and thalamic glutamate inputs onto principal neurons of the basolateral amygdala. Neuropharmacology 2017; 126:224-232. [PMID: 28899729 DOI: 10.1016/j.neuropharm.2017.09.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 08/31/2017] [Accepted: 09/08/2017] [Indexed: 12/13/2022]
Abstract
The basolateral amygdala (BLA) is a key site for crossmodal association of sensory stimuli and an important relay in the neural circuitry of emotion. Indeed, the BLA receives substantial glutamatergic inputs from multiple brain regions including the prefrontal cortex and thalamic nuclei. Modulation of glutamatergic transmission in the BLA regulates stress- and anxiety-related behaviors. Serotonin (5-HT) also plays an important role in regulating stress-related behavior through activation of both pre- and postsynaptic 5-HT receptors. Multiple 5-HT receptors are expressed in the BLA, where 5-HT has been reported to modulate glutamatergic transmission. However, the 5-HT receptor subtype mediating this effect is not yet clear. The aim of this study was to use patch-clamp recordings from BLA neurons in an ex vivo slice preparation to examine 1) the effect of 5-HT on extrinsic sensory inputs, and 2) to determine if any pathway specificity exists in 5-HT regulation of glutamatergic transmission. Two independent input pathways into the BLA were stimulated: the external capsule to mimic cortical input, and the internal capsule to mimic thalamic input. Bath application of 5-HT reversibly reduced the amplitude of evoked excitatory postsynaptic currents (eEPSCs) induced by stimulation of both pathways. The decrease was associated with an increase in the paired-pulse ratio and coefficient of variation of eEPSC amplitude, suggesting 5-HT acts presynaptically. Moreover, the effect of 5-HT in both pathways was mimicked by the selective 5-HT1B receptor agonist CP93129, but not by the 5-HT1A receptor agonist 8-OH DPAT. Similarly the effect of exogenous 5-HT was blocked by the 5-HT1B receptor antagonist GR55562, but not affected by the 5-HT1A receptor antagonist WAY 100635 or the 5-HT2 receptor antagonists pirenperone and MDL 100907. Together these data suggest 5-HT gates cortical and thalamic glutamatergic inputs into the BLA by activating presynaptic 5-HT1B receptors.
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Affiliation(s)
- Ji-Dong Guo
- Division of Behavioral Neuroscience & Psychiatric Disorders, Yerkes National Primate Research Center, Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA.
| | - Brendan M O'Flaherty
- Division of Behavioral Neuroscience & Psychiatric Disorders, Yerkes National Primate Research Center, Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Donald G Rainnie
- Division of Behavioral Neuroscience & Psychiatric Disorders, Yerkes National Primate Research Center, Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
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Adami MB, Barretto-de-Souza L, Duarte JO, Almeida J, Crestani CC. Both N-methyl-D-aspartate and non-N-methyl-D-aspartate glutamate receptors in the bed nucleus of the stria terminalis modulate the cardiovascular responses to acute restraint stress in rats. J Psychopharmacol 2017; 31:674-681. [PMID: 28198211 DOI: 10.1177/0269881117691468] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The bed nucleus of the stria terminalis (BNST) is a forebrain structure that has been implicated on cardiovascular responses evoked by emotional stress. However, the local neurochemical mechanisms mediating the BNST control of stress responses are not fully described. In our study we investigated the involvement of glutamatergic neurotransmission within the BNST in cardiovascular changes evoked by acute restraint stress in rats. For this study, we investigated the effects of bilateral microinjections of selective antagonists of either N-methyl-D-aspartate (NMDA) or non-NMDA glutamate receptors into the BNST on the arterial pressure and heart rate increase and the decrease in tail skin temperature induced by acute restraint stress. Microinjection of the selective NMDA glutamate receptor antagonist LY235959 (1 nmol/100 nL) into the BNST decreased the tachycardiac response to restraint stress, without affecting the arterial pressure increase and the drop in skin temperature. Bilateral BNST treatment with the selective non-NMDA glutamate receptor NBQX (1 nmol/100 nL) decreased the heart rate increase and the fall in tail skin temperature, without affecting the blood pressure increase. These findings indicate a facilitatory influence of BNST glutamatergic neurotransmission via coactivation of local NMDA and non-NMDA receptors on the tachycardiac response to stress, whereas control of sympathetic-mediated cutaneous vasoconstriction is selectively mediated by local non-NMDA glutamate receptors.
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Affiliation(s)
- Mariane B Adami
- 1 Laboratory of Pharmacology, São Paulo State University (UNESP), Araraquara, Brazil
| | - Lucas Barretto-de-Souza
- 1 Laboratory of Pharmacology, São Paulo State University (UNESP), Araraquara, Brazil.,2 Joint Federal University of São Carlos (UFSCar)-UNESP Graduate Program in Physiological Sciences, São Carlos, Brazil
| | - Josiane O Duarte
- 1 Laboratory of Pharmacology, São Paulo State University (UNESP), Araraquara, Brazil
| | - Jeferson Almeida
- 1 Laboratory of Pharmacology, São Paulo State University (UNESP), Araraquara, Brazil.,2 Joint Federal University of São Carlos (UFSCar)-UNESP Graduate Program in Physiological Sciences, São Carlos, Brazil
| | - Carlos C Crestani
- 1 Laboratory of Pharmacology, São Paulo State University (UNESP), Araraquara, Brazil.,2 Joint Federal University of São Carlos (UFSCar)-UNESP Graduate Program in Physiological Sciences, São Carlos, Brazil
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Garzón M, Pickel VM. Electron microscopic localization of M2-muscarinic receptors in cholinergic and noncholinergic neurons of the laterodorsal tegmental and pedunculopontine nuclei of the rat mesopontine tegmentum. J Comp Neurol 2016; 524:3084-103. [PMID: 27038330 DOI: 10.1002/cne.24010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 03/02/2016] [Accepted: 03/28/2016] [Indexed: 01/01/2023]
Abstract
Muscarinic m2 receptors (M2Rs) are implicated in autoregulatory control of cholinergic output neurons located within the pedunculopontine (PPT) and laterodorsal tegmental (LTD) nuclei of the mesopontine tegmentum (MPT). However, these nuclei contain many noncholinergic neurons in which activation of M2R heteroceptors may contribute significantly to the decisive role of the LTD and PPT in sleep-wakefulness. We examined the electron microscopic dual immunolabeling of M2Rs and the vesicular acetylcholine transporter (VAchT) in the MPT of rat brain to identify the potential sites for M2R activation. M2R immunogold labeling was predominately seen in somatodendritic profiles throughout the PPT/LTD complex. In somata, M2R immunogold particles were often associated with Golgi lamellae and cytoplasmic endomembrannes, but were rarely in contact with the plasma membrane, as was commonly seen in dendrites. Approximately 36% of the M2R-labeled somata and 16% of the more numerous M2R-labeled dendrites coexpressed VAchT. M2R and M2R/VAchT-labeled dendritic profiles received synapses from inhibitory- and excitatory-type axon terminals, over 88% of which were unlabeled and others contained exclusively M2R or VAchT immunoreactivity. In axonal profiles M2R immunogold was localized to plasmalemmal and cytoplasmic regions and showed a similar distribution in many VAchT-negative glial profiles. These results provide ultrastructural evidence suggestive of somatic endomembrane trafficking of M2Rs, whose activation serves to regulate the postsynaptic excitatory and inhibitory responses in dendrites of cholinergic and noncholinergic neurons in the MPT. They also suggest the possibility that M2Rs in this brain region mediate the effects of acetylcholine on the release of other neurotransmitters and on glial signaling. J. Comp. Neurol. 524:3084-3103, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Miguel Garzón
- Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina UAM, Madrid, Spain.,Instituto de Investigación Hospital Universitario La Paz (IDIPAZ), Madrid, Spain.,Department of Neuroscience, Brain and Mind Research Institute, Weill Cornell Medical College, New York, New York, USA
| | - Virginia M Pickel
- Department of Neuroscience, Brain and Mind Research Institute, Weill Cornell Medical College, New York, New York, USA
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Gouveia MK, Miguel TT, Busnardo C, Scopinho AA, Corrêa FM, Nunes-de-Souza RL, Crestani CC. Dissociation in control of physiological and behavioral responses to emotional stress by cholinergic neurotransmission in the bed nucleus of the stria terminalis in rats. Neuropharmacology 2016; 101:379-88. [DOI: 10.1016/j.neuropharm.2015.10.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 10/03/2015] [Accepted: 10/10/2015] [Indexed: 11/25/2022]
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Rainnie DG, Hazra R, Dabrowska J, Guo JD, Li CC, Dewitt S, Muly EC. Distribution and functional expression of Kv4 family α subunits and associated KChIP β subunits in the bed nucleus of the stria terminalis. J Comp Neurol 2014; 522:609-25. [PMID: 24037673 DOI: 10.1002/cne.23435] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 06/28/2013] [Accepted: 07/02/2013] [Indexed: 12/22/2022]
Abstract
Regulation of BNSTALG neuronal firing activity is tightly regulated by the opposing actions of the fast outward potassium current, IA , mediated by α subunits of the Kv4 family of ion channels, and the transient inward calcium current, IT . Together, these channels play a critical role in regulating the latency to action potential onset, duration, and frequency, as well as dendritic back-propagation and synaptic plasticity. Previously we have shown that Type I-III BNSTALG neurons express mRNA transcripts for each of the Kv4 α subunits. However, the biophysical properties of native IA channels are critically dependent on the formation of macromolecular complexes of Kv4 channels with a family of chaperone proteins, the potassium channel-interacting proteins (KChIP1-4). Here we used a multidisciplinary approach to investigate the expression and function of Kv4 channels and KChIPs in neurons of the rat BNSTALG . Using immunofluorescence we demonstrated the pattern of localization of Kv4.2, Kv4.3, and KChIP1-4 proteins in the BNSTALG . Moreover, our single-cell reverse-transcription polymerase chain reaction (scRT-PCR) studies revealed that mRNA transcripts for Kv4.2, Kv4.3, and all four KChIPs were differentially expressed in Type I-III BNSTALG neurons. Furthermore, immunoelectron microscopy revealed that Kv4.2 and Kv4.3 channels were primarily localized to the dendrites and spines of BNSTALG neurons, and are thus ideally situated to modulate synaptic transmission. Consistent with this observation, in vitro patch clamp recordings showed that reducing postsynaptic IA in these neurons lowered the threshold for long-term potentiation (LTP) induction. These results are discussed in relation to potential modulation of IA channels by chronic stress.
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Affiliation(s)
- Donald G Rainnie
- Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, Georgia; Division of Behavioral Neuroscience and Psychiatric Disorders, Yerkes National Primate Research Center, Atlanta, Georgia
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Crestani CC, Alves FH, Gomes FV, Resstel LB, Correa FM, Herman JP. Mechanisms in the bed nucleus of the stria terminalis involved in control of autonomic and neuroendocrine functions: a review. Curr Neuropharmacol 2013; 11:141-59. [PMID: 23997750 PMCID: PMC3637669 DOI: 10.2174/1570159x11311020002] [Citation(s) in RCA: 178] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 11/21/2012] [Accepted: 12/03/2012] [Indexed: 12/22/2022] Open
Abstract
The bed nucleus of the stria terminalis (BNST) is a heterogeneous and complex limbic forebrain structure, which plays an important role in controlling autonomic, neuroendocrine and behavioral responses. The BNST is thought to serve as a key relay connecting limbic forebrain structures to hypothalamic and brainstem regions associated with autonomic and neuroendocrine functions. Its control of physiological and behavioral activity is mediated by local action of numerous neurotransmitters. In the present review we discuss the role of the BNST in control of both autonomic and neuroendocrine function. A description of BNST control of cardiovascular and hypothalamus-pituitary-adrenal axisactivity at rest and during physiological challenges (stress and physical exercise) is presented. Moreover, evidence for modulation of hypothalamic magnocellular neurons activity is also discussed. We attempt to focus on the discussion of BNST neurochemical mechanisms. Therefore, the source and targets of neurochemical inputs to BNST subregions and their role in control of autonomic and neuroendocrine function is discussed in details.
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Affiliation(s)
- Carlos C Crestani
- Laboratory of Pharmacology, Department of Natural Active Principles and Toxicology, School of Pharmaceutical Sciences, São Paulo State University, UNESP, Araraquara, SP, 14801-902, Brazil
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Rodríguez-Sierra OE, Turesson HK, Pare D. Contrasting distribution of physiological cell types in different regions of the bed nucleus of the stria terminalis. J Neurophysiol 2013; 110:2037-49. [PMID: 23926040 DOI: 10.1152/jn.00408.2013] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
We characterized the electroresponsive and morphological properties of neurons in the bed nucleus of the stria terminalis (BNST). Previously, Rainnie and colleagues distinguished three cell types in the anterolateral region of BNST (BNST-AL): low-threshold bursting cells (LTB; type II) and regular spiking neurons that display time-dependent (RS; type I) or fast (fIR; type III) inward rectification in the hyperpolarizing direction (Hammack SE, Mania I, Rainnie DG. J Neurophysiol 98: 638-56, 2007). We report that the same neuronal types exist in the anteromedial (AM) and anteroventral (AV) regions of BNST. In addition, we observed two hitherto unreported cell types: late-firing (LF) cells, only seen in BNST-AL, that display a conspicuous delay to firing, and spontaneously active (SA) neurons, only present in BNST-AV, firing continuously at rest. However, the feature that most clearly distinguished the three BNST regions was the incidence of LTB cells (approximately 40-70%) and the strength of their bursting behavior (both higher in BNST-AM and AV relative to AL). The incidence of RS cells was similar in the three regions (∼25%), whereas that of fIR cells was higher in BNST-AL (∼25%) than AV or AM (≤8%). With the use of biocytin, two dominant morphological cell classes were identified but they were not consistently related to particular physiological phenotypes. One neuronal class had highly branched and spiny dendrites; the second had longer but poorly branched and sparsely spiny dendrites. Both often exhibited dendritic varicosities. Since LTB cells prevail in BNST, it will be important to determine what inputs set their firing mode (tonic vs. bursting) and in what behavioral states.
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Affiliation(s)
- Olga E Rodríguez-Sierra
- Center for Molecular and Behavioral Neuroscience, Rutgers State University, Newark, New Jersey; and
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Scarr E, Gibbons AS, Neo J, Udawela M, Dean B. Cholinergic connectivity: it's implications for psychiatric disorders. Front Cell Neurosci 2013; 7:55. [PMID: 23653591 PMCID: PMC3642390 DOI: 10.3389/fncel.2013.00055] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Accepted: 04/12/2013] [Indexed: 01/01/2023] Open
Abstract
Acetylcholine has been implicated in both the pathophysiology and treatment of a number of psychiatric disorders, with most of the data related to its role and therapeutic potential focusing on schizophrenia. However, there is little thought given to the consequences of the documented changes in the cholinergic system and how they may affect the functioning of the brain. This review looks at the cholinergic system and its interactions with the intrinsic neurotransmitters glutamate and gamma-amino butyric acid as well as those with the projection neurotransmitters most implicated in the pathophysiologies of psychiatric disorders; dopamine and serotonin. In addition, with the recent focus on the role of factors normally associated with inflammation in the pathophysiologies of psychiatric disorders, links between the cholinergic system and these factors will also be examined. These interfaces are put into context, primarily for schizophrenia, by looking at the changes in each of these systems in the disorder and exploring, theoretically, whether the changes are interconnected with those seen in the cholinergic system. Thus, this review will provide a comprehensive overview of the connectivity between the cholinergic system and some of the major areas of research into the pathophysiologies of psychiatric disorders, resulting in a critical appraisal of the potential outcomes of a dysregulated central cholinergic system.
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Affiliation(s)
- Elizabeth Scarr
- Department of Psychiatry, The University of MelbourneParkville, VIC, Australia
- Molecular Psychiatry Laboratories, Florey Institute of Neuroscience and Mental HealthParkville, VIC, Australia
| | - Andrew S. Gibbons
- Department of Psychiatry, The University of MelbourneParkville, VIC, Australia
- Molecular Psychiatry Laboratories, Florey Institute of Neuroscience and Mental HealthParkville, VIC, Australia
| | - Jaclyn Neo
- Department of Psychiatry, The University of MelbourneParkville, VIC, Australia
- Molecular Psychiatry Laboratories, Florey Institute of Neuroscience and Mental HealthParkville, VIC, Australia
| | - Madhara Udawela
- Molecular Psychiatry Laboratories, Florey Institute of Neuroscience and Mental HealthParkville, VIC, Australia
- Centre for Neuroscience, The University of MelbourneParkville, VIC, Australia
| | - Brian Dean
- Department of Psychiatry, The University of MelbourneParkville, VIC, Australia
- Molecular Psychiatry Laboratories, Florey Institute of Neuroscience and Mental HealthParkville, VIC, Australia
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Cell-type specific deletion of GABA(A)α1 in corticotropin-releasing factor-containing neurons enhances anxiety and disrupts fear extinction. Proc Natl Acad Sci U S A 2012; 109:16330-5. [PMID: 22992651 DOI: 10.1073/pnas.1119261109] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Corticotropin-releasing factor (CRF) is critical for the endocrine, autonomic, and behavioral responses to stressors, and it has been shown to modulate fear and anxiety. The CRF receptor is widely expressed across a variety of cell types, impeding progress toward understanding the contribution of specific CRF-containing neurons to fear dysregulation. We used a unique CRF-Cre driver transgenic mouse line to remove floxed GABA(A)α1 subunits specifically from CRF neurons [CRF-GABA(A)α1 KO]. This process resulted in mice with decreased GABA(A)α1 expression only in CRF neurons and increased CRF mRNA within the amygdala, bed nucleus of the stria terminalis (BNST) and paraventricular nucleus of the hypothalamus. These mice show normal locomotor and pain responses and no difference in depressive-like behavior or Pavlovian fear conditioning. However, CRF-GABA(A)α1 KO increased anxiety-like behavior and impaired extinction of conditioned fear, coincident with an increase in plasma corticosterone concentration. These behavioral impairments were rescued with systemic or BNST infusion of the CRF antagonist R121919. Infusion of Zolpidem, a GABA(A)α1-preferring benzodiazepine-site agonist, into the BNST of the CRF-GABA(A)α1 KO was ineffective at decreasing anxiety. Electrophysiological findings suggest a disruption in inhibitory current may play a role in these changes. These data indicate that disturbance of CRF containing GABA(A)α1 neurons causes increased anxiety and impaired fear extinction, both of which are symptoms diagnostic for anxiety disorders, such as posttraumatic stress disorder.
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