701
|
MeCP2 regulates the timing of critical period plasticity that shapes functional connectivity in primary visual cortex. Proc Natl Acad Sci U S A 2015; 112:E4782-91. [PMID: 26261347 DOI: 10.1073/pnas.1506499112] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Mutations in methyl-CpG-binding protein 2 (MeCP2) cause Rett syndrome, an autism spectrum-associated disorder with a host of neurological and sensory symptoms, but the pathogenic mechanisms remain elusive. Neuronal circuits are shaped by experience during critical periods of heightened plasticity. The maturation of cortical GABA inhibitory circuitry, the parvalbumin(+) (PV(+)) fast-spiking interneurons in particular, is a key component that regulates the initiation and termination of the critical period. Using MeCP2-null mice, we examined experience-dependent development of neural circuits in the primary visual cortex. The functional maturation of parvalbumin interneurons was accelerated upon vision onset, as indicated by elevated GABA synthetic enzymes, vesicular GABA transporter, perineuronal nets, and enhanced GABA transmission among PV interneurons. These changes correlated with a precocious onset and closure of critical period and deficient binocular visual function in mature animals. Reduction of GAD67 expression rescued the precocious opening of the critical period, suggesting its major role in MECP2-mediated regulation of experience-driven circuit development. Our results identify molecular changes in a defined cortical cell type and link aberrant developmental trajectory to functional deficits in a model of neuropsychiatric disorder.
Collapse
|
702
|
Bachatene L, Bharmauria V, Cattan S, Chanauria N, Rouat J, Molotchnikoff S. Electrophysiological and firing properties of neurons: Categorizing soloists and choristers in primary visual cortex. Neurosci Lett 2015; 604:103-8. [PMID: 26247539 DOI: 10.1016/j.neulet.2015.07.049] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 07/30/2015] [Accepted: 07/31/2015] [Indexed: 11/28/2022]
Abstract
Visual processing in the cortex involves various aspects of neuronal properties such as morphological, electrophysiological and molecular. In particular, the neural firing pattern is an important indicator of dynamic circuitry within a neuronal population. Indeed, in microcircuits, neurons act as soloists or choristers wherein the characteristical activity of a 'soloist' differs from the firing pattern of a 'chorister'. Both cell types correlate their respective firing rate with the global populational activity in a unique way. In the present study, we sought to examine the relationship between the spike shape (thin spike neurons and broad spike neurons) of cortical neurons recorded from V1, their firing levels and their propensity to act as soloists or choristers. We found that thin spike neurons, which exhibited higher levels of firing, generally correlate their activity with the neuronal population (choristers). On the other hand, broad spike neurons showed lower levels of firing and demonstrated weak correlations with the assembly (soloists). A major consequence of the present study is: estimating the correlation of neural spike trains with their neighboring population is a predictive indicator of spike waveforms and firing level. Indeed, we found a continuum distribution of coupling strength ranging from weak correlation-strength (attributed to low-firing neurons) to high correlation-strength (attributed to high-firing neurons). The tendency to exhibit high- or low-firing is conducive to the spike shape of neurons. Our results offer new insights into visual processing by showing how high-firing rate neurons (mostly thin spike neurons) could modulate the neuronal responses within cell-assemblies.
Collapse
Affiliation(s)
- Lyes Bachatene
- Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, Montréal, QC, Canada; Neurosciences Computationnelles et Traitement Intelligent des Signaux NECOTIS, Université de Sherbrooke, Québec, Canada
| | - Vishal Bharmauria
- Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, Montréal, QC, Canada; Neurosciences Computationnelles et Traitement Intelligent des Signaux NECOTIS, Université de Sherbrooke, Québec, Canada
| | - Sarah Cattan
- Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, Montréal, QC, Canada; Neurosciences Computationnelles et Traitement Intelligent des Signaux NECOTIS, Université de Sherbrooke, Québec, Canada
| | - Nayan Chanauria
- Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, Montréal, QC, Canada; Neurosciences Computationnelles et Traitement Intelligent des Signaux NECOTIS, Université de Sherbrooke, Québec, Canada
| | - Jean Rouat
- Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, Montréal, QC, Canada; Neurosciences Computationnelles et Traitement Intelligent des Signaux NECOTIS, Université de Sherbrooke, Québec, Canada
| | - Stéphane Molotchnikoff
- Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, Montréal, QC, Canada; Neurosciences Computationnelles et Traitement Intelligent des Signaux NECOTIS, Université de Sherbrooke, Québec, Canada.
| |
Collapse
|
703
|
Turkheimer FE, Leech R, Expert P, Lord LD, Vernon AC. The brain's code and its canonical computational motifs. From sensory cortex to the default mode network: A multi-scale model of brain function in health and disease. Neurosci Biobehav Rev 2015; 55:211-22. [PMID: 25956253 DOI: 10.1016/j.neubiorev.2015.04.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 04/01/2015] [Accepted: 04/25/2015] [Indexed: 12/21/2022]
Affiliation(s)
| | - Robert Leech
- Division of Brain Sciences, Imperial College London, London, UK
| | - Paul Expert
- Institute of Psychiatry, King's College London, London, UK
| | | | | |
Collapse
|
704
|
Durieux AMS, Horder J, Petrinovic MM. Neuroligin-2 and the tightrope of excitation/inhibition balance in the prefrontal cortex. J Neurophysiol 2015. [PMID: 26224778 DOI: 10.1152/jn.00703.2015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Excitation/inhibition imbalance is implicated in symptoms of neuropsychiatric disorders. We discuss a study by Liang et al. (Mol Psychiatry 20: 850-859, 2015) demonstrating that the conditional knockout of neuroligin-2, a postsynaptic adhesion protein, in the prefrontal cortex of adult mice results in alterations in inhibitory synaptic properties. However, behavioral impairments emerged prior to the development of detectable changes in excitation/inhibition ratio. This suggests there may be network-specific excitation/inhibition ratios, some of which are more vulnerable to disruption than others.
Collapse
Affiliation(s)
- Alice M S Durieux
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London; and
| | - Jamie Horder
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London; and
| | - Marija M Petrinovic
- Roche Pharmaceutical Research & Early Development, Neuroscience Discovery, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| |
Collapse
|
705
|
Shang C, Liu Z, Chen Z, Shi Y, Wang Q, Liu S, Li D, Cao P. A parvalbumin-positive excitatory visual pathway to trigger fear responses in mice. Science 2015; 348:1472-7. [DOI: 10.1126/science.aaa8694] [Citation(s) in RCA: 206] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
|
706
|
Gonzalez-Burgos G, Cho RY, Lewis DA. Alterations in cortical network oscillations and parvalbumin neurons in schizophrenia. Biol Psychiatry 2015; 77:1031-40. [PMID: 25863358 PMCID: PMC4444373 DOI: 10.1016/j.biopsych.2015.03.010] [Citation(s) in RCA: 352] [Impact Index Per Article: 39.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 02/09/2015] [Accepted: 03/07/2015] [Indexed: 11/17/2022]
Abstract
Cognitive deficits are a core clinical feature of schizophrenia but respond poorly to available medications. Thus, understanding the neural basis of these deficits is crucial for the development of new therapeutic interventions. The types of cognitive processes affected in schizophrenia are thought to depend on the precisely timed transmission of information in cortical regions via synchronous oscillations at gamma band frequency. Here, we review 1) data from clinical studies suggesting that induction of frontal cortex gamma oscillations during tasks that engage cognitive or complex perceptual functions is attenuated in schizophrenia; 2) findings from basic neuroscience studies highlighting the features of parvalbumin-positive interneurons that are critical for gamma oscillation production; and 3) results from recent postmortem human brain studies providing additional molecular bases for parvalbumin-positive interneuron alterations in prefrontal cortical circuitry in schizophrenia.
Collapse
Affiliation(s)
| | - Raymond Y Cho
- Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center at Houston, Houston, Texas
| | - David A Lewis
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburg, Pennsylvania.
| |
Collapse
|
707
|
Shigematsu N, Ueta Y, Mohamed AA, Hatada S, Fukuda T, Kubota Y, Kawaguchi Y. Selective Thalamic Innervation of Rat Frontal Cortical Neurons. Cereb Cortex 2015; 26:2689-2704. [PMID: 26045568 DOI: 10.1093/cercor/bhv124] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Most glutamatergic inputs in the neocortex originate from the thalamus or neocortical pyramidal cells. To test whether thalamocortical afferents selectively innervate specific cortical cell subtypes and surface domains, we investigated the distribution patterns of thalamocortical and corticocortical excitatory synaptic inputs in identified postsynaptic cortical cell subtypes using intracellular and immunohistochemical staining combined with confocal laser scanning and electron microscopic observations in 2 thalamorecipient sublayers, lower layer 2/3 (L2/3b) and lower layer 5 (L5b) of rat frontal cortex. The dendrites of GABAergic parvalbumin (PV) cells preferentially received corticocortical inputs in both sublayers. The somata of L2/3b PV cells received thalamic inputs in similar proportions to the basal dendritic spines of L2/3b pyramidal cells, whereas L5b PV somata were mostly innervated by cortical inputs. The basal dendrites of L2/3b pyramidal and L5b corticopontine pyramidal cells received cortical and thalamic glutamatergic inputs in proportion to their local abundance, whereas crossed-corticostriatal pyramidal cells in L5b exhibited a preference for thalamic inputs, particularly in their distal dendrites. Our data demonstrate an exquisite selectivity among thalamocortical afferents in which synaptic connectivity is dependent on the postsynaptic neuron subtype, cortical sublayer, and cell surface domain.
Collapse
Affiliation(s)
- Naoki Shigematsu
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki 444-8787, Japan.,Department of Anatomy and Neurobiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-8556, Japan.,JST, CREST, Tokyo 102-0076, Japan
| | - Yoshifumi Ueta
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki 444-8787, Japan.,JST, CREST, Tokyo 102-0076, Japan
| | - Alsayed A Mohamed
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki 444-8787, Japan.,Department of Anatomy and Embryology, Faculty of Veterinary Medicine, South Valley University, Qena 83523, Arab Republic of Egypt
| | - Sayuri Hatada
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki 444-8787, Japan
| | - Takaichi Fukuda
- Department of Anatomy and Neurobiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-8556, Japan
| | - Yoshiyuki Kubota
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki 444-8787, Japan.,JST, CREST, Tokyo 102-0076, Japan.,Department of Physiological Sciences, SOKENDAI (Graduate University for Advanced Studies), Okazaki 444-8787, Japan
| | - Yasuo Kawaguchi
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki 444-8787, Japan.,JST, CREST, Tokyo 102-0076, Japan.,Department of Physiological Sciences, SOKENDAI (Graduate University for Advanced Studies), Okazaki 444-8787, Japan
| |
Collapse
|
708
|
Abstract
Based on extrapolation from excitatory synapses, it is often assumed that depletion of the releasable pool of synaptic vesicles is the main factor underlying depression at inhibitory synapses. In this issue of Neuron, using subcellular patch-clamp recording from inhibitory presynaptic terminals, Kawaguchi and Sakaba (2015) show that at Purkinje cell-deep cerebellar nuclei neuron synapses, changes in presynaptic action potential waveform substantially contribute to synaptic depression.
Collapse
|
709
|
Soltesz I, Alger BE, Kano M, Lee SH, Lovinger DM, Ohno-Shosaku T, Watanabe M. Weeding out bad waves: towards selective cannabinoid circuit control in epilepsy. Nat Rev Neurosci 2015; 16:264-77. [PMID: 25891509 PMCID: PMC10631555 DOI: 10.1038/nrn3937] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Endocannabinoids are lipid-derived messengers, and both their synthesis and breakdown are under tight spatiotemporal regulation. As retrograde signalling molecules, endocannabinoids are synthesized postsynaptically but activate presynaptic cannabinoid receptor 1 (CB1) receptors to inhibit neurotransmitter release. In turn, CB1-expressing inhibitory and excitatory synapses act as strategically placed control points for activity-dependent regulation of dynamically changing normal and pathological oscillatory network activity. Here, we highlight emerging principles of cannabinoid circuit control and plasticity, and discuss their relevance for epilepsy and related comorbidities. New insights into cannabinoid signalling may facilitate the translation of the recent interest in cannabis-related substances as antiseizure medications to evidence-based treatment strategies.
Collapse
Affiliation(s)
- Ivan Soltesz
- Department of Anatomy and Neurobiology, University of California, Irvine, California 92697, USA
| | - Bradley E Alger
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
| | - Masanobu Kano
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Sang-Hun Lee
- Department of Anatomy and Neurobiology, University of California, Irvine, California 92697, USA
| | - David M Lovinger
- Section on Synaptic Pharmacology, Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, US National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Takako Ohno-Shosaku
- Department of Impairment Study, Graduate School of Medical Science, Kanazawa University, Kanazawa 920-0942, Japan
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| |
Collapse
|
710
|
Girard F, Venail J, Schwaller B, Celio M. The EF-hand Ca2+-binding protein super-family: A genome-wide analysis of gene expression patterns in the adult mouse brain. Neuroscience 2015; 294:116-55. [DOI: 10.1016/j.neuroscience.2015.02.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 02/10/2015] [Accepted: 02/10/2015] [Indexed: 01/13/2023]
|
711
|
Castelnovo A, Ferrarelli F, D'Agostino A. Schizophrenia: from neurophysiological abnormalities to clinical symptoms. Front Psychol 2015; 6:478. [PMID: 25941510 PMCID: PMC4403289 DOI: 10.3389/fpsyg.2015.00478] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 04/02/2015] [Indexed: 01/09/2023] Open
Affiliation(s)
- Anna Castelnovo
- Department of Health Sciences, Università degli Studi di Milano Milan, Italy ; Department of Psychiatry, University of Wisconsin-Madison Madison, WI, USA
| | - Fabio Ferrarelli
- Department of Psychiatry, University of Wisconsin-Madison Madison, WI, USA
| | - Armando D'Agostino
- Department of Health Sciences, Università degli Studi di Milano Milan, Italy
| |
Collapse
|
712
|
Donato F, Chowdhury A, Lahr M, Caroni P. Early- and late-born parvalbumin basket cell subpopulations exhibiting distinct regulation and roles in learning. Neuron 2015; 85:770-86. [PMID: 25695271 DOI: 10.1016/j.neuron.2015.01.011] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 12/11/2014] [Accepted: 01/14/2015] [Indexed: 11/19/2022]
Abstract
Brain networks can support learning by promoting acquisition of task-relevant information or by adhering to validated rules, but the mechanisms involved are poorly understood. Upon learning, local inhibitory parvalbumin (PV)-expressing Basket cell networks can switch to opposite configurations that either favor or interfere with further learning, but how this opposite plasticity is induced and relates to distinct learning requirements has remained unclear. Here, we show that PV Basket cells consist of hitherto unrecognized subpopulations, with distinct schedules of neurogenesis, input connectivities, output target neurons, and roles in learning. Plasticity of hippocampal early-born PV neurons was recruited in rule consolidation, whereas plasticity of late-born PV neurons was recruited in new information acquisition. This involved regulation of early-born neuron plasticity specifically through excitation, and of late-born neuron plasticity specifically through inhibition. Therefore, opposite learning requirements are implemented by distinct local networks involving PV Basket cell subpopulations specifically regulated through inhibition or excitation.
Collapse
Affiliation(s)
- Flavio Donato
- Friedrich Miescher Institut, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Ananya Chowdhury
- Friedrich Miescher Institut, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Maria Lahr
- Friedrich Miescher Institut, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Pico Caroni
- Friedrich Miescher Institut, Maulbeerstrasse 66, 4058 Basel, Switzerland.
| |
Collapse
|
713
|
Regulation of Parvalbumin Basket cell plasticity in rule learning. Biochem Biophys Res Commun 2015; 460:100-3. [DOI: 10.1016/j.bbrc.2015.02.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 02/04/2015] [Indexed: 01/20/2023]
|
714
|
Oscillatory Activity in Developing Prefrontal Networks Results from Theta-Gamma-Modulated Synaptic Inputs. Cell Rep 2015; 11:486-97. [DOI: 10.1016/j.celrep.2015.03.031] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 01/26/2015] [Accepted: 03/11/2015] [Indexed: 11/18/2022] Open
|
715
|
He C, Chen QH, Ye JN, Li C, Yang L, Zhang J, Xia JX, Hu ZA. Functional inactivation of hypocretin 1 receptors in the medial prefrontal cortex affects the pyramidal neuron activity and gamma oscillations: An in vivo multiple-channel single-unit recording study. Neuroscience 2015; 297:1-10. [PMID: 25838117 DOI: 10.1016/j.neuroscience.2015.03.044] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 03/06/2015] [Accepted: 03/19/2015] [Indexed: 01/18/2023]
Abstract
The hypocretin signaling is thought to play a critical role in maintaining wakefulness via stimulating the subcortical arousal pathways. Although the cortical areas, including the medial prefrontal cortex (mPFC), receive dense hypocretinergic fibers and express its receptors, it remains unclear whether the hypocretins can directly regulate the neural activity of the mPFC in vivo. In the present study, using multiple-channel single-unit recording study, we found that infusion of the SB-334867, a blocker for the Hcrtr1, beside the recording sites within the mPFC substantially exerted an inhibitory effect on the putative pyramidal neuron (PPN) activity in naturally behaving rats. In addition, functional blockade of the Hcrtr1 also selectively reduced the power of the gamma oscillations. The PPN activity and the power of the neural oscillations were not affected after microinjection of the TCS-OX2-29, a blocker for the Hcrtr2, within the mPFC. Together, these data indicate that endogenous hypocretins acting on the Hcrtr1 are required for the normal neural activity in the mPFC in vivo, and thus might directly contribute cortical arousal and mPFC-dependent cognitive processes.
Collapse
Affiliation(s)
- C He
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038, PR China
| | - Q-H Chen
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038, PR China
| | - J-N Ye
- Department of Neurology, Xinqiao Hospital, Chongqing 400037, PR China
| | - C Li
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038, PR China
| | - L Yang
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038, PR China
| | - J Zhang
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038, PR China
| | - J-X Xia
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038, PR China.
| | - Z-A Hu
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038, PR China.
| |
Collapse
|
716
|
Ramaswamy S. Exciting times for inhibition: GABAergic synaptic transmission in dentate gyrus interneuron networks. Front Neural Circuits 2015; 9:13. [PMID: 25852487 PMCID: PMC4364173 DOI: 10.3389/fncir.2015.00013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 03/04/2015] [Indexed: 11/16/2022] Open
Affiliation(s)
- Srikanth Ramaswamy
- Blue Brain Project, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne Lausanne, Switzerland
| |
Collapse
|
717
|
Rotaru DC, Olezene C, Miyamae T, Povysheva NV, Zaitsev AV, Lewis DA, Gonzalez-Burgos G. Functional properties of GABA synaptic inputs onto GABA neurons in monkey prefrontal cortex. J Neurophysiol 2015; 113:1850-61. [PMID: 25540225 PMCID: PMC4359991 DOI: 10.1152/jn.00799.2014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 12/23/2014] [Indexed: 11/22/2022] Open
Abstract
In rodent cortex GABAA receptor (GABAAR)-mediated synapses are a significant source of input onto GABA neurons, and the properties of these inputs vary among GABA neuron subtypes that differ in molecular markers and firing patterns. Some features of cortical interneurons are different between rodents and primates, but it is not known whether inhibition of GABA neurons is prominent in the primate cortex and, if so, whether these inputs show heterogeneity across GABA neuron subtypes. We thus studied GABAAR-mediated miniature synaptic events in GABAergic interneurons in layer 3 of monkey dorsolateral prefrontal cortex (DLPFC). Interneurons were identified on the basis of their firing pattern as fast spiking (FS), regular spiking (RS), burst spiking (BS), or irregular spiking (IS). Miniature synaptic events were common in all of the recorded interneurons, and the frequency of these events was highest in FS neurons. The amplitude and kinetics of miniature inhibitory postsynaptic potentials (mIPSPs) also differed between DLPFC interneuron subtypes in a manner correlated with their input resistance and membrane time constant. FS neurons had the fastest mIPSP decay times and the strongest effects of the GABAAR modulator zolpidem, suggesting that the distinctive properties of inhibitory synaptic inputs onto FS cells are in part conferred by GABAARs containing α1 subunits. Moreover, mIPSCs differed between FS and RS interneurons in a manner consistent with the mIPSP findings. These results show that in the monkey DLPFC GABAAR-mediated synaptic inputs are prominent in layer 3 interneurons and may differentially regulate the activity of different interneuron subtypes.
Collapse
Affiliation(s)
- Diana C Rotaru
- Department of Neuroscience, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Cameron Olezene
- Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Takeaki Miyamae
- Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Nadezhda V Povysheva
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Aleksey V Zaitsev
- Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, St. Petersburg, Russia
| | - David A Lewis
- Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Guillermo Gonzalez-Burgos
- Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania;
| |
Collapse
|
718
|
McElvain LE, Faulstich M, Jeanne JM, Moore JD, du Lac S. Implementation of linear sensory signaling via multiple coordinated mechanisms at central vestibular nerve synapses. Neuron 2015; 85:1132-44. [PMID: 25704949 DOI: 10.1016/j.neuron.2015.01.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Revised: 11/10/2014] [Accepted: 01/16/2015] [Indexed: 12/29/2022]
Abstract
Signal transfer in neural circuits is dynamically modified by the recent history of neuronal activity. Short-term plasticity endows synapses with nonlinear transmission properties, yet synapses in sensory and motor circuits are capable of signaling linearly over a wide range of presynaptic firing rates. How do such synapses achieve rate-invariant transmission despite history-dependent nonlinearities? Here, ultrastructural, biophysical, and computational analyses demonstrate that concerted molecular, anatomical, and physiological refinements are required for central vestibular nerve synapses to linearly transmit rate-coded sensory signals. Vestibular synapses operate in a physiological regime of steady-state depression imposed by tonic firing. Rate-invariant transmission relies on brief presynaptic action potentials that delimit calcium influx, large pools of rapidly mobilized vesicles, multiple low-probability release sites, robust postsynaptic receptor sensitivity, and efficient transmitter clearance. Broadband linear synaptic filtering of head motion signals is thus achieved by coordinately tuned synaptic machinery that maintains physiological operation within inherent cell biological limitations.
Collapse
Affiliation(s)
- Lauren E McElvain
- Neurosciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA; Salk Institute for Biological Studies, La Jolla, CA 92037, USA; Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, Av. Brasília, Doca de Pedrouços, Lisbon 1400-038, Portugal.
| | | | - James M Jeanne
- Neurosciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jeffrey D Moore
- Neurosciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Sascha du Lac
- Neurosciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA; Salk Institute for Biological Studies, La Jolla, CA 92037, USA; Howard Hughes Medical Institute, La Jolla, CA 92037, USA; Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| |
Collapse
|
719
|
Becchetti A, Aracri P, Meneghini S, Brusco S, Amadeo A. The role of nicotinic acetylcholine receptors in autosomal dominant nocturnal frontal lobe epilepsy. Front Physiol 2015; 6:22. [PMID: 25717303 PMCID: PMC4324070 DOI: 10.3389/fphys.2015.00022] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 01/14/2015] [Indexed: 11/22/2022] Open
Abstract
Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is a focal epilepsy with attacks typically arising in the frontal lobe during non-rapid eye movement (NREM) sleep. It is characterized by clusters of complex and stereotyped hypermotor seizures, frequently accompanied by sudden arousals. Cognitive and psychiatric symptoms may be also observed. Approximately 12% of the ADNFLE families carry mutations on genes coding for subunits of the heteromeric neuronal nicotinic receptors (nAChRs). This is consistent with the widespread expression of these receptors, particularly the α4β2* subtype, in the neocortex and thalamus. However, understanding how mutant nAChRs lead to partial frontal epilepsy is far from being straightforward because of the complexity of the cholinergic regulation in both developing and mature brains. The relation with the sleep-waking cycle must be also explained. We discuss some possible pathogenetic mechanisms in the light of recent advances about the nAChR role in prefrontal regions as well as the studies carried out in murine models of ADNFLE. Functional evidence points to alterations in prefrontal GABA release, and the synaptic unbalance probably arises during the cortical circuit maturation. Although most of the available functional evidence concerns mutations on nAChR subunit genes, other genes have been recently implicated in the disease, such as KCNT1 (coding for a Na+-dependent K+ channel), DEPD5 (Disheveled, Egl-10 and Pleckstrin Domain-containing protein 5), and CRH (Corticotropin-Releasing Hormone). Overall, the uncertainties about both the etiology and the pathogenesis of ADNFLE point to the current gaps in our knowledge the regulation of neuronal networks in the cerebral cortex.
Collapse
Affiliation(s)
- Andrea Becchetti
- Department of Biotechnology and Biosciences and NeuroMi-Milan Center for Neuroscience, University of Milano-Bicocca Milano, Italy
| | - Patrizia Aracri
- Department of Biotechnology and Biosciences and NeuroMi-Milan Center for Neuroscience, University of Milano-Bicocca Milano, Italy
| | - Simone Meneghini
- Department of Biotechnology and Biosciences and NeuroMi-Milan Center for Neuroscience, University of Milano-Bicocca Milano, Italy
| | - Simone Brusco
- Department of Biotechnology and Biosciences and NeuroMi-Milan Center for Neuroscience, University of Milano-Bicocca Milano, Italy
| | - Alida Amadeo
- Department of Biosciences, University of Milano Milano, Italy
| |
Collapse
|
720
|
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.
Collapse
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
| |
Collapse
|
721
|
Fu Y, Kaneko M, Tang Y, Alvarez-Buylla A, Stryker MP. A cortical disinhibitory circuit for enhancing adult plasticity. eLife 2015; 4:e05558. [PMID: 25626167 PMCID: PMC4337686 DOI: 10.7554/elife.05558] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 01/22/2015] [Indexed: 12/13/2022] Open
Abstract
The adult brain continues to learn and can recover from injury, but the elements and operation of the neural circuits responsible for this plasticity are not known. In previous work, we have shown that locomotion dramatically enhances neural activity in the visual cortex (V1) of the mouse (Niell and Stryker, 2010), identified the cortical circuit responsible for this enhancement (Fu et al., 2014), and shown that locomotion also dramatically enhances adult plasticity (Kaneko and Stryker, 2014). The circuit that is responsible for enhancing neural activity in the visual cortex contains both vasoactive intestinal peptide (VIP) and somatostatin (SST) neurons (Fu et al., 2014). Here, we ask whether this VIP-SST circuit enhances plasticity directly, independent of locomotion and aerobic activity. Optogenetic activation or genetic blockade of this circuit reveals that it is both necessary and sufficient for rapidly increasing V1 cortical responses following manipulation of visual experience in adult mice. These findings reveal a disinhibitory circuit that regulates adult cortical plasticity. DOI:http://dx.doi.org/10.7554/eLife.05558.001
Collapse
Affiliation(s)
- Yu Fu
- Center for Integrative Neuroscience, Department of Physiology, University of California, San Francisco, San Francisco, United States
| | - Megumi Kaneko
- Center for Integrative Neuroscience, Department of Physiology, University of California, San Francisco, San Francisco, United States
| | - Yunshuo Tang
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, United States
| | - Arturo Alvarez-Buylla
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, United States
| | - Michael P Stryker
- Center for Integrative Neuroscience, Department of Physiology, University of California, San Francisco, San Francisco, United States
| |
Collapse
|
722
|
Szabo GG, Schneider CJ, Soltesz I. Resolution revolution: epilepsy dynamics at the microscale. Curr Opin Neurobiol 2015; 31:239-43. [PMID: 25596364 DOI: 10.1016/j.conb.2014.12.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 12/29/2014] [Accepted: 12/30/2014] [Indexed: 11/19/2022]
Abstract
Our understanding of the neuronal mechanisms behind epilepsy dynamics has recently advanced due to the application of novel technologies, monitoring hundreds of neurons with single cell resolution. These developments have provided new theories on the relationship between physiological and pathological states, as well as common motifs for the propagation of paroxysmal activity. Although traditional electroencephalogram (EEG) recordings continue to describe normal network oscillations and abnormal epileptic events within and outside of the seizure focus, analysis of epilepsy dynamics at the microscale has found variability in the composition of macroscopically repetitive epileptiform events. These novel results point to heterogeneity in the underlying dynamics of the disorder, highlighting both the need and potential for more specific and targeted therapies.
Collapse
Affiliation(s)
- Gergely G Szabo
- Department of Anatomy and Neurobiology, University of California, Irvine, CA 92697, USA
| | - Calvin J Schneider
- Department of Anatomy and Neurobiology, University of California, Irvine, CA 92697, USA
| | - Ivan Soltesz
- Department of Anatomy and Neurobiology, University of California, Irvine, CA 92697, USA.
| |
Collapse
|
723
|
Strength and duration of perisomatic GABAergic inhibition depend on distance between synaptically connected cells. Proc Natl Acad Sci U S A 2015; 112:1220-5. [PMID: 25583495 DOI: 10.1073/pnas.1412996112] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
GABAergic perisoma-inhibiting fast-spiking interneurons (PIIs) effectively control the activity of large neuron populations by their wide axonal arborizations. It is generally assumed that the output of one PII to its target cells is strong and rapid. Here, we show that, unexpectedly, both strength and time course of PII-mediated perisomatic inhibition change with distance between synaptically connected partners in the rodent hippocampus. Synaptic signals become weaker due to lower contact numbers and decay more slowly with distance, very likely resulting from changes in GABAA receptor subunit composition. When distance-dependent synaptic inhibition is introduced to a rhythmically active neuronal network model, randomly driven principal cell assemblies are strongly synchronized by the PIIs, leading to higher precision in principal cell spike times than in a network with uniform synaptic inhibition.
Collapse
|
724
|
Megahed T, Hattiangady B, Shuai B, Shetty AK. Parvalbumin and neuropeptide Y expressing hippocampal GABA-ergic inhibitory interneuron numbers decline in a model of Gulf War illness. Front Cell Neurosci 2015; 8:447. [PMID: 25620912 PMCID: PMC4288040 DOI: 10.3389/fncel.2014.00447] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 12/12/2014] [Indexed: 01/30/2023] Open
Abstract
Cognitive dysfunction is amongst the most conspicuous symptoms in Gulf War illness (GWI). Combined exposure to the nerve gas antidote pyridostigmine bromide (PB), pesticides and stress during the Persian Gulf War-1 (PGW-1) are presumed to be among the major causes of GWI. Indeed, our recent studies in rat models have shown that exposure to GWI-related (GWIR) chemicals and mild stress for 4 weeks engenders cognitive impairments accompanied with several detrimental changes in the hippocampus. In this study, we tested whether reduced numbers of hippocampal gamma-amino butyric acid (GABA)-ergic interneurons are among the pathological changes induced by GWIR-chemicals and stress. Animals were exposed to low doses of GWIR-chemicals and mild stress for 4 weeks. Three months after this exposure, subpopulations of GABA-ergic interneurons expressing the calcium binding protein parvalbumin (PV), the neuropeptide Y (NPY) and somatostatin (SS) in the hippocampus were stereologically quantified. Animals exposed to GWIR-chemicals and stress for 4 weeks displayed reduced numbers of PV-expressing GABA-ergic interneurons in the dentate gyrus and NPY-expressing interneurons in the CA1 and CA3 subfields. However, no changes in SS+ interneuron population were observed in the hippocampus. Furthermore, GABA-ergic interneuron deficiency in these animals was associated with greatly diminished hippocampus neurogenesis. Because PV+ and NPY+ interneurons play roles in maintaining normal cognitive function and neurogenesis, and controlling the activity of excitatory neurons in the hippocampus, reduced numbers of these interneurons may be one of the major causes of cognitive dysfunction and reduced neurogenesis observed in GWI. Hence, strategies that improve inhibitory neurotransmission in the hippocampus may prove beneficial for reversing cognitive dysfunction in GWI.
Collapse
Affiliation(s)
- Tarick Megahed
- Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System Temple, TX, USA ; Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine at Scott & White Temple, TX, USA
| | - Bharathi Hattiangady
- Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System Temple, TX, USA ; Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine at Scott & White Temple, TX, USA ; Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine College Station, TX, USA
| | - Bing Shuai
- Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System Temple, TX, USA ; Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine at Scott & White Temple, TX, USA ; Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine College Station, TX, USA
| | - Ashok K Shetty
- Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System Temple, TX, USA ; Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine at Scott & White Temple, TX, USA ; Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine College Station, TX, USA
| |
Collapse
|
725
|
Giant ankyrin-G stabilizes somatodendritic GABAergic synapses through opposing endocytosis of GABAA receptors. Proc Natl Acad Sci U S A 2014; 112:1214-9. [PMID: 25552561 DOI: 10.1073/pnas.1417989112] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
GABAA-receptor-based interneuron circuitry is essential for higher order function of the human nervous system and is implicated in schizophrenia, depression, anxiety disorders, and autism. Here we demonstrate that giant ankyrin-G (480-kDa ankyrin-G) promotes stability of somatodendritic GABAergic synapses in vitro and in vivo. Moreover, giant ankyrin-G forms developmentally regulated and cell-type-specific micron-scale domains within extrasynaptic somatodendritic plasma membranes of pyramidal neurons. We further find that giant ankyrin-G promotes GABAergic synapse stability through opposing endocytosis of GABAA receptors, and requires a newly described interaction with GABARAP, a GABAA receptor-associated protein. We thus present a new mechanism for stabilization of GABAergic interneuron synapses and micron-scale organization of extrasynaptic membrane that provides a rationale for studies linking ankyrin-G genetic variation with psychiatric disease and abnormal neurodevelopment.
Collapse
|
726
|
Yi F, DeCan E, Stoll K, Marceau E, Deisseroth K, Lawrence JJ. Muscarinic excitation of parvalbumin-positive interneurons contributes to the severity of pilocarpine-induced seizures. Epilepsia 2014; 56:297-309. [PMID: 25495999 DOI: 10.1111/epi.12883] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/30/2014] [Indexed: 01/20/2023]
Abstract
OBJECTIVE A common rodent model in epilepsy research employs the muscarinic acetylcholine receptor (mAChR) agonist pilocarpine, yet the mechanisms underlying the induction of pilocarpine-induced seizures (PISs) remain unclear. Global M1 mAChR (M1 R) knockout mice are resistant to PISs, implying that M1 R activation disrupts excitation/inhibition balance. Parvalbumin-positive (PV) inhibitory neurons express M1 Rs, participate in cholinergically induced oscillations, and can enter a state of depolarization block (DB) during epileptiform activity. Here, we test the hypothesis that pilocarpine activation of M1 Rs expressed on PV cells contributes to PISs. METHODS CA1 PV cells in PV-CRE mice were visualized with a floxed YFP or hM3Dq-mCherry adeno-associated virus, or by crossing PV-CRE mice with the RosaYFP reporter line. To eliminate M1 Rs from PV cells, we generated PV-M1 knockout (KO) mice by crossing PV-CRE and floxed M1 mice. Action potential (AP) frequency was monitored during application of pilocarpine (200 μm). In behavioral experiments, locomotion and seizure symptoms were recorded in wild-type (WT) or PV-M1 KO mice during PISs. RESULTS Pilocarpine significantly increased AP frequency in CA1 PV cells into the gamma range. In the continued presence of pilocarpine, a subset (5/7) of PV cells progressed to DB, which was mimicked by hM3Dq activation of Gq-receptor signaling. Pilocarpine-induced depolarization, AP firing at gamma frequency, and progression to DB were prevented in CA1 PV cells of PV-M1 KO mice. Finally, compared to WT mice, PV-M1 KO mice were associated with reduced severity of PISs. SIGNIFICANCE Pilocarpine can directly depolarize PV+ cells via M1 R activation, but a subset of these cells progress to DB. Our electrophysiologic and behavioral results suggest that this mechanism is active during PISs, contributing to a collapse of PV-mediated γ-aminobutyric acid (GABA)ergic inhibition, dysregulation of excitation/inhibition balance, and increased susceptibility to PISs.
Collapse
Affiliation(s)
- Feng Yi
- COBRE Center for Structural and Functional Neuroscience, The University of Montana, Missoula, Montana, U.S.A; Department of Biomedical and Pharmaceutical Sciences, The University of Montana, Missoula, Montana, U.S.A
| | | | | | | | | | | |
Collapse
|
727
|
Hioki H. Compartmental organization of synaptic inputs to parvalbumin-expressing GABAergic neurons in mouse primary somatosensory cortex. Anat Sci Int 2014; 90:7-21. [PMID: 25467527 DOI: 10.1007/s12565-014-0264-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 11/17/2014] [Indexed: 12/19/2022]
Abstract
Parvalbumin (PV)-positive fast-spiking cells in the neocortex are known to generate gamma oscillations by mutual chemical and electrical connections. Recent findings suggest that this rhythm might be responsible for higher-order brain functions, and related to psychiatric disorders. To elucidate the precise structural rules of the connections of PV neurons, we first produced genetic tools. Using a lentiviral expression system, we developed neuron-specific promoters and a new reporter protein that labels the somatodendritic membrane of neurons. We applied the reporter protein to the generation of transgenic mice, and succeeded in visualizing the dendrites and cell bodies of PV neurons efficiently. Then we analyzed excitatory and inhibitory inputs to PV neurons in the primary somatosensory cortex using the mice. Corticocortical glutamatergic inputs were more frequently found on the distal dendrites than on the soma, whereas thalamocortical inputs did not differ between the proximal and distal portions. Corticocortical inhibitory inputs were more densely distributed on the soma than on the dendrites. We further investigated which types of neocortical GABAergic neurons preferred the PV soma over their dendrites. We revealed that the somatic and dendritic compartments principally received GABAergic inputs from vasoactive intestinal polypeptide (VIP)-positive and PV neurons, respectively. This compartmental organization suggests that PV neurons communicate with each other mainly via the dendrites, and that their activity is effectively controlled by the somatic inputs of VIP neurons. These findings provide new insights into the neuronal circuits involving PV neurons, and contribute to a better understanding of brain functions and mental disorders.
Collapse
Affiliation(s)
- Hiroyuki Hioki
- Department of Morphological Brain Science, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan,
| |
Collapse
|
728
|
Stone E, Haario H, Lawrence JJ. A kinetic model for the frequency dependence of cholinergic modulation at hippocampal GABAergic synapses. Math Biosci 2014; 258:162-75. [PMID: 25445738 DOI: 10.1016/j.mbs.2014.09.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 09/25/2014] [Accepted: 09/26/2014] [Indexed: 01/31/2023]
Abstract
In this paper we use a simple model of presynaptic neuromodulation of GABA signaling to decipher paired whole-cell recordings of frequency dependent cholinergic neuromodulation at CA1 parvalbumin-containing basket cell (PV BC)-pyramidal cell synapses. Variance-mean analysis is employed to normalize the data, which is then used to estimate parameters in the mathematical model. Various parameterizations and hidden parameter dependencies are investigated using Markov Chain Monte Carlo (MCMC) parameter estimation techniques. This analysis reveals that frequency dependence of cholinergic modulation requires both calcium-dependent recovery from depression and mAChR-induced inhibition of presynaptic calcium entry. A reduction in calcium entry into the presynaptic terminal in the kinetic model accounted for the frequency-dependent effects of mAChR activation.
Collapse
Affiliation(s)
- Emily Stone
- Department of Mathematical Sciences, The University of Montana Missoula, MT 59812, USA.
| | - Heikki Haario
- Department of Mathematics and Physics, Lappeenranta University of Technology, Lappeenranta, Finland
| | - J Josh Lawrence
- Department of Biomedical and Pharmaceutical Sciences, The University of Montana Missoula, MT 59812, USA
| |
Collapse
|