201
|
|
202
|
Molnár Z, Clowry GJ, Šestan N, Alzu'bi A, Bakken T, Hevner RF, Hüppi PS, Kostović I, Rakic P, Anton ES, Edwards D, Garcez P, Hoerder‐Suabedissen A, Kriegstein A. New insights into the development of the human cerebral cortex. J Anat 2019; 235:432-451. [PMID: 31373394 PMCID: PMC6704245 DOI: 10.1111/joa.13055] [Citation(s) in RCA: 173] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2019] [Indexed: 12/12/2022] Open
Abstract
The cerebral cortex constitutes more than half the volume of the human brain and is presumed to be responsible for the neuronal computations underlying complex phenomena, such as perception, thought, language, attention, episodic memory and voluntary movement. Rodent models are extremely valuable for the investigation of brain development, but cannot provide insight into aspects that are unique or highly derived in humans. Many human psychiatric and neurological conditions have developmental origins but cannot be studied adequately in animal models. The human cerebral cortex has some unique genetic, molecular, cellular and anatomical features, which need to be further explored. The Anatomical Society devoted its summer meeting to the topic of Human Brain Development in June 2018 to tackle these important issues. The meeting was organized by Gavin Clowry (Newcastle University) and Zoltán Molnár (University of Oxford), and held at St John's College, Oxford. The participants provided a broad overview of the structure of the human brain in the context of scaling relationships across the brains of mammals, conserved principles and recent changes in the human lineage. Speakers considered how neuronal progenitors diversified in human to generate an increasing variety of cortical neurons. The formation of the earliest cortical circuits of the earliest generated neurons in the subplate was discussed together with their involvement in neurodevelopmental pathologies. Gene expression networks and susceptibility genes associated to neurodevelopmental diseases were discussed and compared with the networks that can be identified in organoids developed from induced pluripotent stem cells that recapitulate some aspects of in vivo development. New views were discussed on the specification of glutamatergic pyramidal and γ-aminobutyric acid (GABA)ergic interneurons. With the advancement of various in vivo imaging methods, the histopathological observations can be now linked to in vivo normal conditions and to various diseases. Our review gives a general evaluation of the exciting new developments in these areas. The human cortex has a much enlarged association cortex with greater interconnectivity of cortical areas with each other and with an expanded thalamus. The human cortex has relative enlargement of the upper layers, enhanced diversity and function of inhibitory interneurons and a highly expanded transient subplate layer during development. Here we highlight recent studies that address how these differences emerge during development focusing on diverse facets of our evolution.
Collapse
Affiliation(s)
- Zoltán Molnár
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Gavin J. Clowry
- Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
| | - Nenad Šestan
- Department of Neuroscience, Yale University School of MedicineNew HavenCTUSA
| | - Ayman Alzu'bi
- Department of Basic Medical SciencesFaculty of MedicineYarmouk UniversityIrbidJordan
| | | | | | - Petra S. Hüppi
- Dept. de l'enfant et de l'adolescentHôpitaux Universitaires de GenèveGenèveSwitzerland
| | - Ivica Kostović
- Croatian Institute for Brain ResearchSchool of MedicineUniversity of ZagrebZagrebCroatia
| | - Pasko Rakic
- Department of Neuroscience, Yale University School of MedicineNew HavenCTUSA
| | - E. S. Anton
- UNC Neuroscience CenterDepartment of Cell and Molecular PhysiologyThe University of North Carolina School of MedicineChapel HillNCUSA
| | - David Edwards
- Centre for the Developing BrainBiomedical Engineering and Imaging Sciences,King's College LondonLondonUK
| | - Patricia Garcez
- Federal University of Rio de Janeiro, UFRJInstitute of Biomedical SciencesRio de JaneiroBrazil
| | | | - Arnold Kriegstein
- Department of NeurologyUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell ResearchUCSFSan FranciscoCAUSA
| |
Collapse
|
203
|
Abstract
The study of interneuron diversity in the spinal cord is complex and needs new models that can accelerate discovery. In this issue, Hoang et al. (2018) use ESC-derived neurons to create simplified microcircuits to study spinal interneuron diversification, connectivity, and function.
Collapse
Affiliation(s)
- Francisco J Alvarez
- Department of Physiology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| |
Collapse
|
204
|
Abstract
Neural stem cells (NSCs) within the hippocampal niche integrate local cues, such as activity of inhibitory interneurons, into their homeostatic fate choices. Now in Cell Stem Cell, Bao et al. (2017) describe how these local interneurons relay signals from distal brain regions to govern NSC quiescence and activation.
Collapse
Affiliation(s)
- Nannan Guo
- Center for Regenerative Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Stem Cell Institute, Cambridge, MA 02138, USA; Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Amar Sahay
- Center for Regenerative Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Stem Cell Institute, Cambridge, MA 02138, USA; Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA; BROAD Institute of Harvard and MIT, Cambridge, MA 02142, USA.
| |
Collapse
|
205
|
Castro DC, Bruchas MR. A Motivational and Neuropeptidergic Hub: Anatomical and Functional Diversity within the Nucleus Accumbens Shell. Neuron 2019; 102:529-552. [PMID: 31071288 PMCID: PMC6528838 DOI: 10.1016/j.neuron.2019.03.003] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 02/22/2019] [Accepted: 03/01/2019] [Indexed: 01/14/2023]
Abstract
The mesocorticolimbic pathway is canonically known as the "reward pathway." Embedded within the center of this circuit is the striatum, a massive and complex network hub that synthesizes motivation, affect, learning, cognition, stress, and sensorimotor information. Although striatal subregions collectively share many anatomical and functional similarities, it has become increasingly clear that it is an extraordinarily heterogeneous region. In particular, the nucleus accumbens (NAc) medial shell has repeatedly demonstrated that the rules dictated by more dorsal aspects of the striatum do not apply or are even reversed in functional logic. These discrepancies are perhaps most easily captured when isolating the functions of various neuromodulatory peptide systems within the striatum. Endogenous peptides are thought to play a critical role in modulating striatal signals to either amplify or dampen evoked behaviors. Here we describe the anatomical-functional backdrop upon which several neuropeptides act within the NAc to modulate behavior, with a specific emphasis on nucleus accumbens medial shell and stress responsivity. Additionally, we propose that, as the field continues to dissect fast neurotransmitter systems within the NAc, we must also provide considerable contextual weight to the roles local peptides play in modulating these circuits to more comprehensively understand how this important subregion gates motivated behaviors.
Collapse
Affiliation(s)
- Daniel C Castro
- Center for Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, WA 98195, USA; Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195, USA; Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Michael R Bruchas
- Center for Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, WA 98195, USA; Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195, USA; Department of Pharmacology, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|
206
|
Slankster E, Odell SR, Mathew D. Strength in diversity: functional diversity among olfactory neurons of the same type. J Bioenerg Biomembr 2019; 51:65-75. [PMID: 30604088 PMCID: PMC6382560 DOI: 10.1007/s10863-018-9779-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 11/13/2018] [Indexed: 01/01/2023]
Abstract
Most animals depend upon olfaction to find food, mates, and to avoid predators. An animal's olfactory circuit helps it sense its olfactory environment and generate critical behavioral responses. The general architecture of the olfactory circuit, which is conserved across species, is made up of a few different neuronal types including first-order receptor neurons, second- and third-order neurons, and local interneurons. Each neuronal type differs in their morphology, physiology, and neurochemistry. However, several recent studies have suggested that there is intrinsic diversity even among neurons of the same type and that this diversity is important for neural function. In this review, we first examine instances of intrinsic diversity observed among individual types of olfactory neurons. Next, we review potential genetic and experience-based plasticity mechanisms that underlie this diversity. Finally, we consider the implications of intrinsic neuronal diversity for circuit function. Overall, we hope to highlight the importance of intrinsic diversity as a previously underestimated property of circuit function.
Collapse
Affiliation(s)
- Eryn Slankster
- Department of Biology, University of Nevada, 1664 N. Virginia St., MS: 0314, Reno, NV, 89557, USA
| | - Seth R Odell
- Department of Biology, University of Nevada, 1664 N. Virginia St., MS: 0314, Reno, NV, 89557, USA
- Integrated Neuroscience Program, University of Nevada, Reno, NV, 89557, USA
| | - Dennis Mathew
- Department of Biology, University of Nevada, 1664 N. Virginia St., MS: 0314, Reno, NV, 89557, USA.
- Integrated Neuroscience Program, University of Nevada, Reno, NV, 89557, USA.
| |
Collapse
|
207
|
Qiu C, Feng Z, Zheng L, Huang L. Frequency-Dependent Inhibition Induced by Stimulations in Rat Hippocampus. Annu Int Conf IEEE Eng Med Biol Soc 2018; 2018:2182-2185. [PMID: 30440837 DOI: 10.1109/embc.2018.8512613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Deep brain stimulation (DBS) has a good prospect in treating brain diseases such as epilepsy. However, its therapeutic mechanism is undetermined yet. To investigate the inhibitory effects of DBS acting on the downstream neurons in target region, 1-min pulse trains of orthodromic stimulations with various frequencies (10 - 100 Hz) were applied to the Schaffer collaterals of hippocampal CA1 region in anaesthetized rats. Unit spikes of downstream interneurons and pyramidal cells were detected and analyzed. Interneurons activated by the stimulation through mono-synaptic connections were recognized based on short latencies. Their firing was used as an index of stimulation-induced inhibition. Results showed that during stimulations with pulse frequency of 20 Hz, the mean firing rate of mono-synaptically-activated interneurons was significantly higher than the value during 10 Hz stimulations. Afterward, even if the pulse frequency increased to 100 Hz, the mean firing rate of the interneurons did not change significantly. However, only during stimulations with lower frequencies (10, 20 Hz), the firing of pyramidal cells was suppressed by the stimulation-activated interneurons. The inhibitory effects of interneurons were weakened during stimulations with higher frequencies (50 and 100 Hz). De-synchronous firing of interneurons induced by high-frequency stimulation might cause the loss of effective inhibition on the principal neurons. These findings provide new information for advancing the application of DBS.
Collapse
|
208
|
Pastore VP, Massobrio P, Godjoski A, Martinoia S. Identification of excitatory-inhibitory links and network topology in large-scale neuronal assemblies from multi-electrode recordings. PLoS Comput Biol 2018; 14:e1006381. [PMID: 30148879 PMCID: PMC6128636 DOI: 10.1371/journal.pcbi.1006381] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 09/07/2018] [Accepted: 07/20/2018] [Indexed: 12/23/2022] Open
Abstract
Functional-effective connectivity and network topology are nowadays key issues for studying brain physiological functions and pathologies. Inferring neuronal connectivity from electrophysiological recordings presents open challenges and unsolved problems. In this work, we present a cross-correlation based method for reliably estimating not only excitatory but also inhibitory links, by analyzing multi-unit spike activity from large-scale neuronal networks. The method is validated by means of realistic simulations of large-scale neuronal populations. New results related to functional connectivity estimation and network topology identification obtained by experimental electrophysiological recordings from high-density and large-scale (i.e., 4096 electrodes) microtransducer arrays coupled to in vitro neural populations are presented. Specifically, we show that: (i) functional inhibitory connections are accurately identified in in vitro cortical networks, providing that a reasonable firing rate and recording length are achieved; (ii) small-world topology, with scale-free and rich-club features are reliably obtained, on condition that a minimum number of active recording sites are available. The method and procedure can be directly extended and applied to in vivo multi-units brain activity recordings. The balance between excitation and inhibition is fundamental for proper brain functions and for this reason is precisely regulated in adult cortices. Impaired excitation/inhibition balance is often associated with several neurological disorders, such as epilepsy, autism and schizophrenia. However, estimating functional inhibitory connections is not an easy task and few methods are available to identify such connections from electrophysiological data. Here we present a cross-correlation based method to identify both excitatory and inhibitory functional connections in large-scale neuronal networks. The method is applicable to both in vitro and in vivo spike data recordings. Once a connectivity map (i.e. a graph) is obtained, we characterized the associated topology by means of classical graph theory metrics to unveil functional architecture. In this work, we analyze in vitro cortical networks probed by means of large-scale microelectrode arrays (i.e., 4096 sensors) and we derive network topologies from spike data. The functional organization found is called “small-world and scale-free” and is the same organization found in cortical in vivo brain regions by means of different experimental methods. We also show that to obtain reliable information about network architecture at least a network with a hundred of nodes-neurons is needed.
Collapse
Affiliation(s)
- Vito Paolo Pastore
- University of Genova, Dept. of Informatics, Bioengineering, Robotics and System Engineering, Genova, Italy
| | - Paolo Massobrio
- University of Genova, Dept. of Informatics, Bioengineering, Robotics and System Engineering, Genova, Italy
| | - Aleksandar Godjoski
- University of Genova, Dept. of Informatics, Bioengineering, Robotics and System Engineering, Genova, Italy
- 3Brain gmbh, Wädenswil, Switzerland
| | - Sergio Martinoia
- University of Genova, Dept. of Informatics, Bioengineering, Robotics and System Engineering, Genova, Italy
- CNR—Institute of Biophysics, Genova, Italy
- * E-mail:
| |
Collapse
|
209
|
Safavi S, Dwarakanath A, Kapoor V, Werner J, Hatsopoulos NG, Logothetis NK, Panagiotaropoulos TI. Nonmonotonic spatial structure of interneuronal correlations in prefrontal microcircuits. Proc Natl Acad Sci U S A 2018; 115:E3539-E3548. [PMID: 29588415 PMCID: PMC5899496 DOI: 10.1073/pnas.1802356115] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Correlated fluctuations of single neuron discharges, on a mesoscopic scale, decrease as a function of lateral distance in early sensory cortices, reflecting a rapid spatial decay of lateral connection probability and excitation. However, spatial periodicities in horizontal connectivity and associational input as well as an enhanced probability of lateral excitatory connections in the association cortex could theoretically result in nonmonotonic correlation structures. Here, we show such a spatially nonmonotonic correlation structure, characterized by significantly positive long-range correlations, in the inferior convexity of the macaque prefrontal cortex. This functional connectivity kernel was more pronounced during wakefulness than anesthesia and could be largely attributed to the spatial pattern of correlated variability between functionally similar neurons during structured visual stimulation. These results suggest that the spatial decay of lateral functional connectivity is not a common organizational principle of neocortical microcircuits. A nonmonotonic correlation structure could reflect a critical topological feature of prefrontal microcircuits, facilitating their role in integrative processes.
Collapse
Affiliation(s)
- Shervin Safavi
- Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
- International Max Planck Research School for Cognitive and Systems Neuroscience, University of Tübingen, 72074 Tübingen, Germany
| | - Abhilash Dwarakanath
- Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Vishal Kapoor
- Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
- International Max Planck Research School for Cognitive and Systems Neuroscience, University of Tübingen, 72074 Tübingen, Germany
| | - Joachim Werner
- Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | | | - Nikos K Logothetis
- Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany;
- Division of Imaging Science and Biomedical Engineering, University of Manchester, 72074 Manchester, United Kingdom
| | - Theofanis I Panagiotaropoulos
- Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany;
- Cognitive Neuroimaging Unit, Commissariat à l'Énergie Atomique, Division Sciences de la Vie (DSV), Institut d'imagerie Biomédicale (I2BM), INSERM, Université Paris-Sud, Université Paris-Saclay, Neurospin Center, 91191 Gif/Yvette, France
| |
Collapse
|
210
|
Bandopadhayay P, Stiles CD. Population Control: Cortical Interneurons Modulate Oligodendrogenesis. Neuron 2017; 94:415-417. [PMID: 28472644 DOI: 10.1016/j.neuron.2017.04.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
During central nervous system development, oligodendrocytes must be formed in proportion to the number of neurons requiring their services. In this issue of Neuron, Voronova et al. (2017) show how cortical interneurons modulate oligodendrogenesis through a cytokine-mediated paracrine interaction.
Collapse
Affiliation(s)
- Pratiti Bandopadhayay
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center and Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Charles D Stiles
- Department of Neurobiology, Harvard Medical School and Dana-Farber Cancer Institute, Boston, MA 02115, USA.
| |
Collapse
|
211
|
Turrero García M, Mazzola E, Harwell CC. Lineage Relationships Do Not Drive MGE/PoA-Derived Interneuron Clustering in the Brain. Neuron 2017; 92:52-58. [PMID: 27710790 DOI: 10.1016/j.neuron.2016.09.034] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Revised: 08/17/2016] [Accepted: 09/07/2016] [Indexed: 11/19/2022]
Abstract
Neocortical excitatory and inhibitory neurons derive from distinct progenitor domains during embryonic development and migrate to their final positions, where they assemble into functional circuits. This process appears to be influenced by lineage relationships among locally born excitatory neurons, raising the intriguing possibility that this might be true for cortical interneurons. Two recent articles by the Fishell laboratory and our own used retrovirus-encoded DNA barcodes as unambiguous lineage-tracing tools to address this question, finding that clonally related inhibitory interneurons dispersed widely across the forebrain (Harwell et al., 2015; Mayer et al., 2015). This Matters Arising Response addresses the Sultan et al. (2016) Matters Arising paper, published concurrently in Neuron, where the authors reanalyze the datasets from both studies and propose a new interpretation, whereby clonally related interneurons would be considered clustered according to specific spatial constraints. After studying the report from Sultan et al. (2016) and carefully revisiting previously published studies, we find no evidence of lineage-dependent MGE/PoA-derived interneuron clustering in the forebrain.
Collapse
Affiliation(s)
| | - Emanuele Mazzola
- Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA
| | - Corey C Harwell
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
212
|
Barron H, Hafizi S, Mizrahi R. Towards an Integrated View of Early Molecular Changes Underlying Vulnerability to Social Stress in Psychosis. Mod Trends Pharmacopsychiatry 2017; 31:96-106. [PMID: 28738349 DOI: 10.1159/000470810] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Psychotic disorders are heterogeneous and complex, involving many putative causal factors interacting along the course of disease development. Many of the factors implicated in the pathogenesis of psychosis also appear to be involved in disease onset and subsequent neuroprogression. Herein, we highlight the pertinent literature implicating inflammation and oxidative stress in the pathogenesis of psychosis, and the potential contribution of N-methyl-D-aspartate receptors (NMDARs). We also emphasize the role of peripubertal social stress in psychosis, and the ways in which hippocampal dysfunction can mediate dysregulation of the hypothalamic-pituitary-adrenal axis and cortisol release. Finally, we propose a model wherein inflammation and oxidative stress act as a first hit, producing altered parvalbumin interneuron development, NMDAR hypofunction, microglial priming, and sensitivity to a second hit of peripubertal social stress. With a greater understanding of how these factors interact, it may be possible to detect, prevent, and treat psychosis more effectively.
Collapse
|
213
|
Ng HX, Lee EP, Cavanagh BL, Britto JM, Tan SS. A method for isolating cortical interneurons sharing the same birthdays for gene expression studies. Exp Neurol 2017; 295:36-45. [PMID: 28511841 DOI: 10.1016/j.expneurol.2017.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 04/13/2017] [Accepted: 05/13/2017] [Indexed: 11/19/2022]
Abstract
The two neuronal populations in the cortex, pyramidal neurons and interneurons, can be separated based on neurotransmitter identity, however, within this segregation a large degree of diversity exists. Investigations into the molecular diversity of neurons are impeded by the inability to isolate cell populations born at different times for gene expression analysis. Developing interneurons may be distinguished by the expression of Glutamic Acid Decarboxylase-67 (GAD67). Neuronal birthdating using nucleoside analogs is an effective means of identifying coetaneous interneurons. Using these two features, neurotransmitter identity and birthdating, we have developed a method to isolate migrating interneurons using fluorescent-activated cell sorting (FACS) for RNA extraction and gene expression analysis. We utilized 5-ethynyl-2'-deoxyuridine (EdU) to birthdate interneuron cohorts and the GAD67 knock-in GFP transgenic mice to identify interneurons. In combination, we achieved simultaneous detection of GFP and EdU signals during FACS sorting of coetaneous interneurons with minimum loss of RNA integrity. RNA quality was deemed to be satisfactory by quantitative polymerase chain reaction (qPCR) for the interneuron-specific transcript Gad67.
Collapse
Affiliation(s)
- Hui Xuan Ng
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia; University of Melbourne, Parkville, VIC, Australia.
| | - Ean Phing Lee
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia
| | | | - Joanne M Britto
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia; University of Melbourne, Parkville, VIC, Australia
| | - Seong-Seng Tan
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia; University of Melbourne, Parkville, VIC, Australia.
| |
Collapse
|
214
|
Paiva DDS, Romariz SAA, Valente MF, Moraes LB, Covolan L, Calcagnotto ME, Monteiro Longo B. Transplantation of inhibitory precursor cells from medial ganglionic eminence produces distinct responses in two different models of acute seizure induction. Epilepsy Behav 2017; 70:125-130. [PMID: 28427019 DOI: 10.1016/j.yebeh.2017.03.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 03/07/2017] [Accepted: 03/07/2017] [Indexed: 11/19/2022]
Abstract
Medial ganglionic eminence (MGE) is one of the sources of inhibitory interneurons during development. Following transplantation in postnatal developing brain, MGE cells can increase local inhibition suggesting a possible protection to GABAergic dysfunction in brain disorders, such as epilepsy. Since it has been shown that MGE-derived cells harvested as neurospheres are able to suppress seizures, it might be important to investigate whether these protective effects would change in different seizure models. Here, we used pentylenetetrazole-(PTZ) and maximal electroshock (MES)-induced seizure models to test whether the transplantation of MGE cells would increase the threshold to trigger acute seizures. When transplanted into the neocortex (layers 3-4) of neonatal mice (postnatal days 3-4), MGE cells were able to survive and were mainly found in piriform cortex, fimbria, and ventricular wall regions. Additionally, the number of GFP+ cells found in the brains of mice induced with PTZ and MES differed significantly and suggests proliferation and larger survival rate of MGE-transplanted cells after PTZ, but not MES-induced seizures. Following transplantation, there was a reduction in the number of animals presenting mild and severe seizures induced by PTZ. Furthermore, MGE-cell transplantation was able to increase threshold to seizures induced by PTZ, but was not able to prevent seizure spread induced by MES.
Collapse
Affiliation(s)
- Daisyléa de Souza Paiva
- Laboratório de Neurofisiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil
| | | | - Maria Fernanda Valente
- Laboratório de Neurofisiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil
| | - Luiz Bruno Moraes
- Laboratório de Neurofisiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil
| | - Luciene Covolan
- Laboratório de Neurofisiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil
| | | | - Beatriz Monteiro Longo
- Laboratório de Neurofisiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil.
| |
Collapse
|
215
|
Yu F, Zhao ZY, He T, Yu YQ, Li Z, Chen J. Temporal and spatial dynamics of peripheral afferent-evoked activity in the dorsal horn recorded in rat spinal cord slices. Brain Res Bull 2017; 131:183-191. [PMID: 28458040 DOI: 10.1016/j.brainresbull.2017.04.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Revised: 02/13/2017] [Accepted: 04/21/2017] [Indexed: 01/07/2023]
Abstract
In the present study, multi-electrode array recording was used to examine dorsal horn activity following stimulation of primary afferents in a rat dorsal root attached-spinal cord slice preparation. The multi-electrode array probe was placed under the dorsal horn slice and local field potentials evoked by stimulation on the dorsal root were analyzed. Three kinds of dorsal root-evoked responses were identified. In lamina IIo, local field potentials exhibited P1 (peak latency 1.46±0.08ms), N1 (2.77±0.18ms, n=12), N2 (7.31±0.48ms), N3 (12.12±0.73ms) and P2(18.30±0.80ms) waves. In lamina IIi local field potentials exhibited P (1.99±0.10ms), N1 (3.35±0.17ms) and N2 (8.58±0.44ms) waves. In laminae III-VI, local field potentials exhibited P1 (3.01±0.07ms), P2 (7.02±0.21ms) and N waves (22.57±0.79ms). Sweep spread was calculated by two dimensional current source density (2D-CSD) analysis. Both α-amino-3-hydroxy-5-methylisoxazole-4-propionic a/kainate and N-methyl-d-aspartate-type glutamate receptors participated in this neuronal circuitry. Morphine diminished local field potentials. Gabapentin diminished the negative components in lamina II and P2 component in lamina IIo, but increased the positive components in lamina IIi and laminae III-VI. The present study revealed that functional dorsal horn activity was preserved in the spinal cord slice preparation. Glutamatergic synapses were crucially involved in information processing. Opioid interneurons and gabapentin may play a modulatory role in regulating signal flows in the dorsal horn. Taken together, these results identify a spatio-temporal profile of dorsal horn activity evoked by dorsal root stimulation, and implicate glutamatergic and opioidergic receptors and gabapentin in this activity.
Collapse
Affiliation(s)
- Fang Yu
- State Key Laboratory of Cancer Biology & Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xi'an, Shaanxi Province, 710038, PR China; Jinan Military General Hospital, Jinan, Shandong Province, 250031, PR China
| | - Zhen-Yu Zhao
- Institute for Biomedical Sciences of Pain and Institute for Functional Brain Disorders, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi Province, 710038, PR China; Jinan Military General Hospital, Jinan, Shandong Province, 250031, PR China
| | - Ting He
- Institute for Biomedical Sciences of Pain and Institute for Functional Brain Disorders, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi Province, 710038, PR China
| | - Yao-Qing Yu
- Institute for Biomedical Sciences of Pain and Institute for Functional Brain Disorders, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi Province, 710038, PR China
| | - Zhen Li
- Institute for Biomedical Sciences of Pain and Institute for Functional Brain Disorders, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi Province, 710038, PR China
| | - Jun Chen
- Institute for Biomedical Sciences of Pain and Institute for Functional Brain Disorders, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi Province, 710038, PR China.
| |
Collapse
|
216
|
Northcutt BD, Dyhr JP, Higgins CM. An insect-inspired model for visual binding I: learning objects and their characteristics. Biol Cybern 2017; 111:185-206. [PMID: 28303333 DOI: 10.1007/s00422-017-0715-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Accepted: 02/27/2017] [Indexed: 06/06/2023]
Abstract
Visual binding is the process of associating the responses of visual interneurons in different visual submodalities all of which are responding to the same object in the visual field. Recently identified neuropils in the insect brain termed optic glomeruli reside just downstream of the optic lobes and have an internal organization that could support visual binding. Working from anatomical similarities between optic and olfactory glomeruli, we have developed a model of visual binding based on common temporal fluctuations among signals of independent visual submodalities. Here we describe and demonstrate a neural network model capable both of refining selectivity of visual information in a given visual submodality, and of associating visual signals produced by different objects in the visual field by developing inhibitory neural synaptic weights representing the visual scene. We also show that this model is consistent with initial physiological data from optic glomeruli. Further, we discuss how this neural network model may be implemented in optic glomeruli at a neuronal level.
Collapse
Affiliation(s)
- Brandon D Northcutt
- Department of Electrical and Computer Engineering, University of Arizona, 1230 E. Speedway Blvd., Tucson, AZ, 85721, USA.
| | - Jonathan P Dyhr
- Department of Biology, Northwest University, 5520 108th Ave. N.E., Kirkland, WA, 98033, USA
| | - Charles M Higgins
- Departments of Neuroscience and Electrical/Computer Engineering, University of Arizona, 1040 E. 4th St., Tucson, AZ, 85721, USA
| |
Collapse
|
217
|
Fu H, Rodriguez GA, Herman M, Emrani S, Nahmani E, Barrett G, Figueroa HY, Goldberg E, Hussaini SA, Duff KE. Tau Pathology Induces Excitatory Neuron Loss, Grid Cell Dysfunction, and Spatial Memory Deficits Reminiscent of Early Alzheimer's Disease. Neuron 2017; 93:533-541.e5. [PMID: 28111080 DOI: 10.1016/j.neuron.2016.12.023] [Citation(s) in RCA: 160] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 10/20/2016] [Accepted: 12/15/2016] [Indexed: 11/18/2022]
Abstract
The earliest stages of Alzheimer's disease (AD) are characterized by the formation of mature tangles in the entorhinal cortex and disorientation and confusion when navigating familiar places. The medial entorhinal cortex (MEC) contains specialized neurons called grid cells that form part of the spatial navigation system. Here we show in a transgenic mouse model expressing mutant human tau predominantly in the EC that the formation of mature tangles in old mice was associated with excitatory cell loss and deficits in grid cell function, including destabilized grid fields and reduced firing rates, as well as altered network activity. Overt tau pathology in the aged mice was accompanied by spatial memory deficits. Therefore, tau pathology initiated in the entorhinal cortex could lead to deficits in grid cell firing and underlie the deterioration of spatial cognition seen in human AD.
Collapse
Affiliation(s)
- Hongjun Fu
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Gustavo A Rodriguez
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Mathieu Herman
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Sheina Emrani
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Eden Nahmani
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Geoffrey Barrett
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Helen Y Figueroa
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Eliana Goldberg
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - S Abid Hussaini
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA; Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA.
| | - Karen E Duff
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA; Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA; Department of Integrative Neuroscience, New York State Psychiatric Institute, New York, NY 10032, USA.
| |
Collapse
|
218
|
Barth A, Burkhalter A, Callaway EM, Connors BW, Cauli B, DeFelipe J, Feldmeyer D, Freund T, Kawaguchi Y, Kisvarday Z, Kubota Y, McBain C, Oberlaender M, Rossier J, Rudy B, Staiger JF, Somogyi P, Tamas G, Yuste R. Comment on "Principles of connectivity among morphologically defined cell types in adult neocortex". Science 2016; 353:1108. [PMID: 27609882 DOI: 10.1126/science.aaf5663] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 08/03/2016] [Indexed: 01/15/2023]
Abstract
Jiang et al (Research Article, 27 November 2015, aac9462) describe detailed experiments that substantially add to the knowledge of cortical microcircuitry and are unique in the number of connections reported and the quality of interneuron reconstruction. The work appeals to experts and laypersons because of the notion that it unveils new principles and provides a complete description of cortical circuits. We provide a counterbalance to the authors' claims to give those less familiar with the minutiae of cortical circuits a better sense of the contributions and the limitations of this study.
Collapse
Affiliation(s)
- Alison Barth
- 159C Mellon Institute, Department of Biological Sciences, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, USA
| | - Andreas Burkhalter
- Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Edward M Callaway
- Systems Neurobiology Laboratories, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | - Barry W Connors
- Department of Neuroscience, Division of Biology and Medicine, Brown University, Providence, RI 02912, USA
| | - Bruno Cauli
- Neuroscience Paris Seine (NPS), Cortical Network and Neurovascular Coupling (CNNC), CNRS UMR 8246, Inserm U 1130, UPMC UM 119, Université Pierre et Marie Curie, 9 Quai Saint Bernard, 75005 Paris, France
| | - Javier DeFelipe
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnologia Biomedica, Universidad Politecnica de Madrid, Campus Montegancedo S/N, Pozuelo de Alarcon, 28223 Madrid, Spain. Instituto Cajal (CSIC), Avenida Doctor Arce 37, 28002 Madrid, Spain
| | - Dirk Feldmeyer
- Institut für Neurowissenschaften und Medizin (INM-2), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Tamas Freund
- Department of Cellular and Network Neurobiology, Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine, Hungarian Academy of Sciences, H-1450 Budapest, POB 67, Hungary
| | - Yasuo Kawaguchi
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, 5-1 Myodaiji-Higashiyama, Okazaki, Aichi 444-8787, Japan
| | - Zoltan Kisvarday
- University of Debrecen, Department of Anatomy, Histology, Embryology, Laboratory for Cortical Systems Neuroscience, Nagyerdei krt. 98, 4012 Debrecen, Hungary
| | - Yoshiyuki Kubota
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, 5-1 Myodaiji-Higashiyama, Okazaki, Aichi 444-8787, Japan
| | - Chris McBain
- Laboratory of Cellular and Synaptic Neurophysiology, National Institute of Child Health and Human Development, 35 Convent Drive MSC3715, Bethesda, MD 20892, USA
| | - Marcel Oberlaender
- Max Planck Institute for Biological Cybernetics, Computational Neuroanatomy Group, D-72076 Tubingen, Germany
| | - Jean Rossier
- Neuroscience Paris Seine, Univerisité Pierre et Marie Curie (UPMC) Paris VI, 7-9 Quai Saint Bernard, 75005 Paris, France
| | - Bernardo Rudy
- Neuroscience Institute, Department of Anesthesiology, Perioperative Care, and Pain Medicine, New York University School of Medicine, Smilow Research Center, 522 First Avenue, New York, NY 10016, USA.
| | - Jochen F Staiger
- University Medicine Goettingen, Center for Anatomy, Institute for Neuroanatomy, Kreuzbergring 36, D-37075 Goettingen, Germany.
| | - Peter Somogyi
- Medical Research Council Brain Network Dynamics Unit, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3TH, UK
| | - Gabor Tamas
- Research Group for Cortical Microcircuits of the Hungarian Academy of Sciences, Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép Fasor 52, Szeged, H-6726 Hungary
| | - Rafael Yuste
- Kavli institute of Brain Science, Columbia University, Department of Biological Sciences, West 120 Street, New York, NY 10027, USA
| |
Collapse
|
219
|
Bissonette GB, Bae MH, Suresh T, Jaffe DE, Powell EM. Prefrontal cognitive deficits in mice with altered cerebral cortical GABAergic interneurons. Behav Brain Res 2013; 259:143-51. [PMID: 24211452 DOI: 10.1016/j.bbr.2013.10.051] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 10/25/2013] [Accepted: 10/30/2013] [Indexed: 12/26/2022]
Abstract
Alterations of inhibitory GABAergic neurons are implicated in multiple psychiatric and neurological disorders, including schizophrenia, autism and epilepsy. In particular, interneuron deficits in prefrontal areas, along with presumed decreased inhibition, have been reported in several human patients. The majority of forebrain GABAergic interneurons arise from a single subcortical source before migrating to their final regional destination. Factors that govern the interneuron populations have been identified, demonstrating that a single gene mutation may globally affect forebrain structures or a single area. In particular, mice lacking the urokinase plasminogen activator receptor (Plaur) gene have decreased GABAergic interneurons in frontal and parietal, but not caudal, cortical regions. Plaur assists in the activation of hepatocyte growth factor/scatter factor (HGF/SF), and several of the interneuron deficits are correlated with decreased levels of HGF/SF. In some cortical regions, the interneuron deficit can be remediated by endogenous overexpression of HGF/SF. In this study, we demonstrate decreased parvalbumin-expressing interneurons in the medial frontal cortex, but not in the hippocampus or basal lateral amygdala in the Plaur null mouse. The Plaur null mouse demonstrates impaired medial frontal cortical function in extinction of cued fear conditioning and the inability to form attentional sets. Endogenous HGF/SF overexpression increased the number of PV-expressing cells in medial frontal cortical areas to levels greater than found in wildtype mice, but did not remediate the behavioral deficits. These data suggest that proper medial frontal cortical function is dependent upon optimum levels of inhibition and that a deficit or excess of interneuron numbers impairs normal cognition.
Collapse
Affiliation(s)
- Gregory B Bissonette
- Program in Neuroscience, University of Maryland, Baltimore, Baltimore, MD 21201, USA
| | - Mihyun H Bae
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Tejas Suresh
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - David E Jaffe
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Elizabeth M Powell
- Program in Neuroscience, University of Maryland, Baltimore, Baltimore, MD 21201, USA; Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
| |
Collapse
|
220
|
Francius C, Harris A, Rucchin V, Hendricks TJ, Stam FJ, Barber M, Kurek D, Grosveld FG, Pierani A, Goulding M, Clotman F. Identification of multiple subsets of ventral interneurons and differential distribution along the rostrocaudal axis of the developing spinal cord. PLoS One 2013; 8:e70325. [PMID: 23967072 PMCID: PMC3744532 DOI: 10.1371/journal.pone.0070325] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 06/17/2013] [Indexed: 01/06/2023] Open
Abstract
The spinal cord contains neuronal circuits termed Central Pattern Generators (CPGs) that coordinate rhythmic motor activities. CPG circuits consist of motor neurons and multiple interneuron cell types, many of which are derived from four distinct cardinal classes of ventral interneurons, called V0, V1, V2 and V3. While significant progress has been made on elucidating the molecular and genetic mechanisms that control ventral interneuron differentiation, little is known about their distribution along the antero-posterior axis of the spinal cord and their diversification. Here, we report that V0, V1 and V2 interneurons exhibit distinct organizational patterns at brachial, thoracic and lumbar levels of the developing spinal cord. In addition, we demonstrate that each cardinal class of ventral interneurons can be subdivided into several subsets according to the combinatorial expression of different sets of transcription factors, and that these subsets are differentially distributed along the rostrocaudal axis of the spinal cord. This comprehensive molecular profiling of ventral interneurons provides an important resource for investigating neuronal diversification in the developing spinal cord and for understanding the contribution of specific interneuron subsets on CPG circuits and motor control.
Collapse
Affiliation(s)
- Cédric Francius
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Audrey Harris
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Vincent Rucchin
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Timothy J. Hendricks
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Floor J. Stam
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Melissa Barber
- CNRS UMR 7592, Institut Jacques Monod, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Dorota Kurek
- Erasmus MC Stem Cell Institute, Department of Cell Biology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Frank G. Grosveld
- Erasmus MC Stem Cell Institute, Department of Cell Biology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Alessandra Pierani
- CNRS UMR 7592, Institut Jacques Monod, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Martyn Goulding
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Frédéric Clotman
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
- * E-mail:
| |
Collapse
|
221
|
Abstract
Gamma rhythms (30-100 Hz) are an extensively studied synchronous brain state responsible for a number of sensory, memory, and motor processes. Experimental evidence suggests that fast-spiking interneurons are responsible for carrying the high frequency components of the rhythm, while regular-spiking pyramidal neurons fire sparsely. We propose that a combination of spike frequency adaptation and global inhibition may be responsible for this behavior. Excitatory neurons form several clusters that fire every few cycles of the fast oscillation. This is first shown in a detailed biophysical network model and then analyzed thoroughly in an idealized model. We exploit the fact that the timescale of adaptation is much slower than that of the other variables. Singular perturbation theory is used to derive an approximate periodic solution for a single spiking unit. This is then used to predict the relationship between the number of clusters arising spontaneously in the network as it relates to the adaptation time constant. We compare this to a complementary analysis that employs a weak coupling assumption to predict the first Fourier mode to destabilize from the incoherent state of an associated phase model as the external noise is reduced. Both approaches predict the same scaling of cluster number with respect to the adaptation time constant, which is corroborated in numerical simulations of the full system. Thus, we develop several testable predictions regarding the formation and characteristics of gamma rhythms with sparsely firing excitatory neurons.
Collapse
Affiliation(s)
- Zachary P Kilpatrick
- Department of Mathematics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
| | | |
Collapse
|
222
|
Honda T, Yamazaki T, Tanaka S, Nagao S, Nishino T. Stimulus-dependent state transition between synchronized oscillation and randomly repetitive burst in a model cerebellar granular layer. PLoS Comput Biol 2011; 7:e1002087. [PMID: 21779155 PMCID: PMC3136428 DOI: 10.1371/journal.pcbi.1002087] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 04/28/2011] [Indexed: 11/18/2022] Open
Abstract
Information processing of the cerebellar granular layer composed of granule and Golgi cells is regarded as an important first step toward the cerebellar computation. Our previous theoretical studies have shown that granule cells can exhibit random alternation between burst and silent modes, which provides a basis of population representation of the passage-of-time (POT) from the onset of external input stimuli. On the other hand, another computational study has reported that granule cells can exhibit synchronized oscillation of activity, as consistent with observed oscillation in local field potential recorded from the granular layer while animals keep still. Here we have a question of whether an identical network model can explain these distinct dynamics. In the present study, we carried out computer simulations based on a spiking network model of the granular layer varying two parameters: the strength of a current injected to granule cells and the concentration of Mg2+ which controls the conductance of NMDA channels assumed on the Golgi cell dendrites. The simulations showed that cells in the granular layer can switch activity states between synchronized oscillation and random burst-silent alternation depending on the two parameters. For higher Mg2+ concentration and a weaker injected current, granule and Golgi cells elicited spikes synchronously (synchronized oscillation state). In contrast, for lower Mg2+ concentration and a stronger injected current, those cells showed the random burst-silent alternation (POT-representing state). It is suggested that NMDA channels on the Golgi cell dendrites play an important role for determining how the granular layer works in response to external input. Intensive studies of Pavlovian delay eyelid conditioning suggest that the cerebellum can memorize a passage-of-time (POT) from the onset of an external stimulus. To account for possible mechanisms of such POT representation, some network models have been proposed to show that granule cells (grcs) in the cerebellar granular layer can exhibit random alternation of burst and silent modes under feedback inhibition from Golgi cells, resulting in non-recurrent generation of active granule cells populations. On the other hand, the oscillation of local field potential (LFP) has been observed in the cerebellar granular layer when animals stay at rest. Some network models have shown that grcs can elicit synchronous spikes in an oscillatory manner. These qualitatively different neural dynamics of the granular layer raises a question of how they can be accounted for by an identical network in the granular layer. Here we report that grc activities of a biologically plausible spiking network model undergo the state transition between synchronized oscillation and random burst-silent alternation, depending on the activation of NMDA channels on the Golgi cell dendrites and the strength of a current injected to grcs.
Collapse
Affiliation(s)
- Takeru Honda
- Department of Information and Communication Engineering, Graduate School of Electro-Communications, The University of Electro-Communications, Chofu-shi, Tokyo, Japan
- Laboratory for Motor Learning Control, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
| | - Tadashi Yamazaki
- Strategic Planning Unit, RIKEN BSI-TOYOTA Collaboration Center, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
| | - Shigeru Tanaka
- Department of Informatics, Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu-shi, Tokyo, Japan
| | - Soichi Nagao
- Laboratory for Motor Learning Control, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
| | - Tetsuro Nishino
- Department of Informatics, Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu-shi, Tokyo, Japan
- * E-mail:
| |
Collapse
|
223
|
Li N, Downey JE, Bar-Shir A, Gilad AA, Walczak P, Kim H, Joel SE, Pekar JJ, Thakor NV, Pelled G. Optogenetic-guided cortical plasticity after nerve injury. Proc Natl Acad Sci U S A 2011; 108:8838-43. [PMID: 21555573 PMCID: PMC3102379 DOI: 10.1073/pnas.1100815108] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Peripheral nerve injury causes sensory dysfunctions that are thought to be attributable to changes in neuronal activity occurring in somatosensory cortices both contralateral and ipsilateral to the injury. Recent studies suggest that distorted functional response observed in deprived primary somatosensory cortex (S1) may be the result of an increase in inhibitory interneuron activity and is mediated by the transcallosal pathway. The goal of this study was to develop a strategy to manipulate and control the transcallosal activity to facilitate appropriate plasticity by guiding the cortical reorganization in a rat model of sensory deprivation. Since transcallosal fibers originate mainly from excitatory pyramidal neurons somata situated in laminae III and V, the excitatory neurons in rat S1 were engineered to express halorhodopsin, a light-sensitive chloride pump that triggers neuronal hyperpolarization. Results from electrophysiology, optical imaging, and functional MRI measurements are concordant with that within the deprived S1, activity in response to intact forepaw electrical stimulation was significantly increased by concurrent illumination of halorhodopsin over the healthy S1. Optogenetic manipulations effectively decreased the adverse inhibition of deprived cortex and revealed the major contribution of the transcallosal projections, showing interhemispheric neuroplasticity and thus, setting a foundation to develop improved rehabilitation strategies to restore cortical functions.
Collapse
Affiliation(s)
- Nan Li
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD 21205
- Department of Biomedical Engineering and
| | - John E. Downey
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD 21205
| | - Amnon Bar-Shir
- Cellular Imaging Section, Vascular Biology Program, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205; and
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287
| | - Assaf A. Gilad
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD 21205
- Cellular Imaging Section, Vascular Biology Program, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205; and
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287
| | - Piotr Walczak
- Cellular Imaging Section, Vascular Biology Program, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205; and
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287
| | - Heechul Kim
- Cellular Imaging Section, Vascular Biology Program, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205; and
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287
| | - Suresh E. Joel
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD 21205
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287
| | - James J. Pekar
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD 21205
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287
| | | | - Galit Pelled
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD 21205
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287
| |
Collapse
|
224
|
Abstract
Octopamine plays an important role in many behaviors in invertebrates. It acts via binding to G protein coupled receptors located on the plasma membrane of responsive cells. Several distinct subtypes of octopamine receptors have been found in invertebrates, yet little is known about the expression pattern of these different receptor subtypes and how each subtype may contribute to different behaviors. One honey bee (Apis mellifera) octopamine receptor, AmOA1, was recently cloned and characterized. Here we continue to characterize the AmOA1 receptor by investigating its distribution in the honey bee brain. We used two independent antibodies produced against two distinct peptides in the carboxyl-terminus to study the distribution of the AmOA1 receptor in the honey bee brain. We found that both anti-AmOA1 antibodies revealed labeling of cell body clusters throughout the brain and within the following brain neuropils: the antennal lobes; the calyces, pedunculus, vertical (alpha, gamma) and medial (beta) lobes of the mushroom body; the optic lobes; the subesophageal ganglion; and the central complex. Double immunofluorescence staining using anti-GABA and anti-AmOA1 receptor antibodies revealed that a population of inhibitory GABAergic local interneurons in the antennal lobes express the AmOA1 receptor in the cell bodies, axons and their endings in the glomeruli. In the mushroom bodies, AmOA1 receptors are expressed in a subpopulation of inhibitory GABAergic feedback neurons that ends in the visual (outer half of basal ring and collar regions) and olfactory (lip and inner basal ring region) calyx neuropils, as well as in the collar and lip zones of the vertical and medial lobes. The data suggest that one effect of octopamine via AmOA1 in the antennal lobe and mushroom body is to modulate inhibitory neurons.
Collapse
Affiliation(s)
- Irina Sinakevitch
- Arizona State University, School of Life Sciences, Tempe, Arizona, United States of America
| | - Julie A. Mustard
- Arizona State University, School of Life Sciences, Tempe, Arizona, United States of America
| | - Brian H. Smith
- Arizona State University, School of Life Sciences, Tempe, Arizona, United States of America
- * E-mail:
| |
Collapse
|
225
|
|
226
|
Abstract
The retina of the compound eye contains a patterned spatial array of receptor cell groups whose symmetry and component numerical constancy allow the unique identification of individual cells. The axon connection patterns arising from the retina similarly are uniquely identifiable and relate by simple consistnet transpositons to the retinal position of their somata. The coincidence of these features and the epidermal origin or retinula cells provides a model system for the developmental analysis of neural patterns. It is known that the retina develops by a wave of determinative mitoses and subsequent cellular differentiation, transmitted inductively from a posteriorly situated differentiation centre, which passes over the prospective eye field independently of the growing axon connections with the optic lobe. The ganglion cells of the optic lobe are similarly produced in a temporal sequence but their subsequent differentiation depends on centripetal innervation and proceeds as a wave initiated in the retina. Axon growth between the retina and optic neuropiles occurs in this temporal sequence, appears largely non-exploratory and dependent on mechanical guidance. By contrast, individual axon connections within the neuropile form probabilistically by extensive filopod explorations between cones. Both growth between and growth within the neuropile depend upon features in the pattern of retinal development which are discussed.
Collapse
|
227
|
Chung L, Moore SD. Cholecystokinin enhances GABAergic inhibitory transmission in basolateral amygdala. Neuropeptides 2007; 41:453-63. [PMID: 17904218 DOI: 10.1016/j.npep.2007.08.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Revised: 07/13/2007] [Accepted: 08/11/2007] [Indexed: 11/25/2022]
Abstract
The neuropeptide cholecystokinin (CCK) is anxiogenic in studies of human and animal behavior. As the amygdala formation has been implicated in generation of emotional states such as anxiety, we tested the effect of CCK on spontaneous synaptic events in the basolateral amygdala (BLA) using whole cell patch recordings in rat brain slice preparation. We found that CCK increased the frequency of spontaneous inhibitory postsynaptic potentials (sIPSPs) and currents (sIPSCs). This effect was blocked by the fast sodium channel blocker tetrodotoxin (TTX), indicating that the CCK effect is likely mediated by direct excitation of GABAergic interneurons. The CCK(B) receptor subtype antagonist, CR2945, blocked the CCK effect, while CCK4, a specific CCK(B) agonist, increased sIPSC frequency. We hypothesize that these actions may underlie the anxiogenic effects of CCK observed in behavioral studies.
Collapse
Affiliation(s)
- L Chung
- Department of Psychiatry, Duke University Medical Center, Durham, NC 27710, USA
| | | |
Collapse
|
228
|
Valeriani M, Fierro B, Brighina F. Brain excitability in migraine: Hyperexcitability or inhibited inhibition? Pain 2007; 132:219-20; author reply 220-2. [PMID: 17870239 DOI: 10.1016/j.pain.2007.08.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Accepted: 08/13/2007] [Indexed: 11/20/2022]
|
229
|
Curra A, Pierelli F, Coppola G, Barbanti P, Buzzi MG, Galeotti F, Serrao M, Truini A, Casali C, Pauri F, Cruccu G. Shortened cortical silent period in facial muscles of patients with migraine. Pain 2007; 132:124-31. [PMID: 17574759 DOI: 10.1016/j.pain.2007.05.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2007] [Revised: 04/22/2007] [Accepted: 05/10/2007] [Indexed: 11/24/2022]
Abstract
Despite intensive neurophysiological research, evidence is lacking to show whether abnormal cortical excitability in migraine reflects a primary cortical disturbance or reduced control by thalamo-cortical loops. One way to contribute to the scientific discussion on this topic is to deliver transcranial magnetic stimulation (TMS) and test the cortical silent period (SP) recorded in facial muscles. The facial-muscle SP is a purely cortical phenomenon that reflects the excitability of inhibitory interneurons, and can disclose changes in cortical inhibition even in patients without documented primary lesions of the motor cortices. To test the interictal excitability of cortical motor inhibitory interneurons in migraine, we investigated the facial-SP in patients with migraine with and without aura between attacks. In 26 patients and 15 age-matched controls, high-intensity magnetic stimuli were delivered with a round coil centered at the vertex during a maximal muscle contraction. Electromyographic responses were recorded from surface electrodes placed over the subjects' perioral muscles. Facial SPs were significantly shorter in patients than in controls. The SP shortening provides neurophysiological evidence showing hypoexcitability of cortical inhibitory neurons in patients with migraine between attacks. Despite a possible primary deficit of cortical inhibitory interneurons in migraine, we favor the interpretation of a secondary disfacilitation by hypoactive thalamo-cortical loops. Based on this interpretation, the interictal reduced cortical inhibition documented by the shortened SP could be considered the motor counterpart of the reduced preactivation excitability level in the sensory cortices purported to explain why cortical evoked responses habituate poorly in patients with migraine.
Collapse
Affiliation(s)
- Antonio Curra
- Department of Neurological Sciences, La Sapienza University, Rome, Italy.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
230
|
Abstract
Temporal lobe epilepsy is the most common type of epilepsy in adults, and its pathophysiology remains unclear. Layer II stellate cells of the entorhinal cortex, which are hyperexcitable in animal models of temporal lobe epilepsy, provide the predominant synaptic input to the hippocampal dentate gyrus. Previous studies have ascribed the hyperexcitability of layer II stellate cells to GABAergic interneurons becoming "dormant" after disconnection from their excitatory synaptic inputs, which has been reported to occur during preferential loss of layer III pyramidal cells. We used whole-cell recording from slices of entorhinal cortex in pilocarpine-treated epileptic rats to test the dormant interneuron hypothesis. Hyperexcitability appeared as multiple action potentials and prolonged depolarizations evoked in layer II stellate cells of epileptic rats but not controls. However, blockade of glutamatergic synaptic transmission caused similar percentage reductions in the frequency of spontaneous IPSCs in layer II stellate cells of control and epileptic rats, suggesting similar levels of excitatory synaptic input to GABAergic interneurons. Direct recordings and biocytin labeling revealed two major types of interneurons in layer III whose excitatory synaptic drive in epileptic animals was undiminished. Interneurons in layer III did not appear to be dormant; therefore, we tested whether loss of GABAergic synapses might underlie hyperexcitability of layer II stellate cells. Stereological evidence of fewer GABAergic interneurons, fewer gephyrin-immunoreactive punctae, and reduced frequency of spontaneous IPSCs and miniature IPSCs (recorded in tetrodotoxin) confirmed that layer II stellate cell hyperexcitability is attributable, at least in part, to reduced inhibitory synaptic input.
Collapse
Affiliation(s)
- Sanjay S Kumar
- Department of Comparative Medicine, Stanford University, Stanford, California 94305, USA
| | | |
Collapse
|
231
|
Abstract
The purpose of this study was to examine the level of agreement and patterns of disagreement between home-care patient and informant reports of depressive symptoms. The authors interviewed a sample of 355 older home-care patients and their informants using the Structured Diagnostic Interview for DSM-IV (R. L. Spitzer, M. Gibbon, & J. B. Williams, 1995). Informants reported more psychological symptoms than patients, and this type of discrepancy was higher for patients with cognitive impairment and patients who had younger informants. Younger informants also reported more cognitive symptoms, whereas patients were more likely to report suicidal thoughts or ideation if they were not cognitively impaired. The patterns of these discrepancies may reflect age- and cohort-related response bias in the reports of depressive symptoms obtained from older adults.
Collapse
Affiliation(s)
- Gail J McAvay
- Program on Aging, Yale University, New Haven, CT 06510, USA.
| | | | | | | |
Collapse
|
232
|
Abstract
The middle ear muscle (MEM) reflexes function to protect the inner ear from intense acoustic stimuli and to reduce acoustic masking. Sound presented to the same side or to the opposite side activates the MEM reflex on both sides. The ascending limbs of these pathways must be the auditory nerve fibers originating in the cochlea and terminating in the cochlear nucleus, the first relay station for all ascending auditory information. The descending limbs project from the motoneurons in the brainstem to the MEMs on both sides, causing their contraction. Although the ascending and descending pathways are well described, the cochlear nucleus interneurons that mediate these reflex pathways have not been identified. In order to localize the MEM reflex interneurons, we developed a physiologically based reflex assay in the rat that can be used to determine the integrity of the reflex pathways after experimental manipulations. This assay monitored the change in tone levels and distortion product otoacoustic emissions within the ear canal in one ear during the presentation of a reflex-eliciting sound stimulus in the contralateral ear. Preliminary findings using surgical transection and focal lesioning of the auditory brainstem to interrupt the MEM reflexes suggest that MEM reflex interneurons are located in the ventral cochlear nucleus.
Collapse
Affiliation(s)
- Daniel J Lee
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts 02114, USA.
| | | | | | | |
Collapse
|
233
|
Sandberg A, Stålberg E. Reflexes in prior polio and their relation to weakness and anterior horn cell loss. J Electromyogr Kinesiol 2005; 16:611-20. [PMID: 16377213 DOI: 10.1016/j.jelekin.2005.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 09/28/2005] [Accepted: 10/05/2005] [Indexed: 10/25/2022] Open
Abstract
The aim of this study was to evaluate the reflex pattern in patients with prior polio and to relate these findings to the degree of anterior horn cell (AHC) involvement and loss of muscle force. Twenty-five prior polio subjects were investigated with electromyography (EMG), force testing and reflex studies, which included the patellar and Achilles reflex, H-reflex, T-response and interlimb reflex (ILR). The clinical reflexes, H/M-ratio and T-response amplitude at rest were positively correlated with force and negatively correlated with the degree of AHC loss. The H/M-ratio was decreased compared with age matched controls. ILR was present in 68% of the prior polio patients but did not exist in controls. The presence of the ILR was not correlated with the degree of AHC loss or force. The reflex studies gave two main findings. The first is reduced excitability of monosynaptic connections in the motor neuron pool, which is related to weakness. The other is the presence of ILR as an indicator of interneuronal hyper-excitability, which is not related to weakness.
Collapse
Affiliation(s)
- Arne Sandberg
- Department of Clinical Neurophysiology, Neurocentre, Uppsala University Hospital, SE-751 85 Uppsala, Sweden.
| | | |
Collapse
|
234
|
Gloveli T, Dugladze T, Rotstein HG, Traub RD, Monyer H, Heinemann U, Whittington MA, Kopell NJ. Orthogonal arrangement of rhythm-generating microcircuits in the hippocampus. Proc Natl Acad Sci U S A 2005; 102:13295-300. [PMID: 16141320 PMCID: PMC1201613 DOI: 10.1073/pnas.0506259102] [Citation(s) in RCA: 184] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
As a structure involved in learning and memory, the hippocampus functions as a network. The functional differentiation along the longitudinal axis of the hippocampus is poorly demarcated in comparison with the transverse axis. Using patch clamp recordings in conjunction with post hoc anatomy, we have examined the pattern of connectivity and the functional differentiation along the long axis of the hippocampus. Here, we provide anatomical and physiological evidence that the prominent rhythmic network activities of the hippocampus, the behavior-specific gamma and theta oscillations, are seen predominantly along the transverse and longitudinal axes respectively. This orthogonal relationship is the result of the axonal field trajectories and the consequential interaction of the principal cells and major interneuron subtypes involved in generating each rhythm. Thus, the axonal arborization patterns of hippocampal inhibitory cells may represent a structural framework for the spatiotemporal distribution of activity observed within the hippocampus.
Collapse
Affiliation(s)
- Tengis Gloveli
- Institute of Neurophysiology, Charité-Universitätsmedizin Berlin, Tucholskystrasse 2, 10117 Berlin, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
235
|
Abstract
The generation of rhythmic patterns by neuronal networks is a complex phenomenon, relying on the interaction of numerous intrinsic and synaptic currents, as well as modulatory agents. To investigate the functional contribution of an individual ionic current to rhythmic pattern generation in a network, we constructed a hybrid system composed of a silicon model neuron and a heart interneuron from the heartbeat timing network of the medicinal leech. When the model neuron and a heart interneuron are connected by inhibitory synapses, they produce rhythmic activity similar to that observed in the heartbeat network. We focused our studies on investigating the functional role of the hyperpolarization-activated inward current (I(h)) on the rhythmic bursts produced by the network. By introducing changes in both the model and the heart interneuron, we showed that I(h) determines both the period of rhythmic bursts and the balance of activity between the two sides of the network, because the amount and the activation/deactivation time constant of I(h) determines the length of time that a neuron spends in the inhibited phase of its burst cycle. Moreover, we demonstrated that the model neuron is an effective replacement for a heart interneuron and that changes made in the model can accurately mimic similar changes made in the living system. Finally, we used a previously developed mathematical model (Hill et al. 2001) of two mutually inhibitory interneurons to corroborate these findings. Our results demonstrated that this hybrid system technique is advantageous for investigating neuronal properties that are inaccessible with traditional techniques.
Collapse
Affiliation(s)
- Michael Sorensen
- Laboratory for Neuroengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0363, USA
| | | | | | | |
Collapse
|
236
|
Abstract
The spike-time reliability of motoneurons in the Aplysia buccal motor ganglion was studied as a function of the frequency content and the relative amplitude of the fluctuations in the neuronal input, calculated as the coefficient of variation (CV). Measurements of spike-time reliability to sinusoidal and aperiodic inputs, as well as simulations of a noisy leaky integrate-and-fire neuron stimulated by spike trains drawn from a periodically modulated process, demonstrate that there are three qualitatively different CV-dependent mechanisms that determine reliability: noise-dominated (CV < 0.05 for Aplysia motoneurons) where spike timing is unreliable regardless of frequency content; resonance-dominated (CV approximately 0.05-0.25) where reliability is reduced by removal of input frequencies equal to motoneuron firing rate; and amplitude-dominated (CV >0.35) where reliability depends on input frequencies greater than motoneuron firing rate. In the resonance-dominated regime, changes in the activity of the presynaptic inhibitory interneuron B4/5 alter motoneuron spike-time reliability. The increases or decreases in reliability occur coincident with small changes in motoneuron spiking rate due to changes in interneuron activity. Injection of a hyperpolarizing current into the motoneuron reproduces the interneuron-induced changes in reliability. The rate-dependent changes in reliability can be understood from the phase-locking properties of regularly spiking motoneurons to periodic inputs. Our observations demonstrate that the ability of a neuron to support a spike-time code can be actively controlled by varying the properties of the neuron and its input.
Collapse
Affiliation(s)
- John D Hunter
- Department of Neurology, University of Chicago, Chicago, Illinois 60615, USA
| | | |
Collapse
|
237
|
KOLMODIN GM, SKOGLUND CR. Properties and functional differentiation of interneurons in the ventral horn of the cat's lumbar cord as revealed by intracellular recording. ACTA ACUST UNITED AC 2003; 10:505-6. [PMID: 14353094 DOI: 10.1007/bf02166186] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
238
|
Abstract
Recent studies in rodents have suggested that some cortical GABAergic interneurons arise within the neuroepithelium of the subcortical telencephalon then migrate dorsally into the cerebral cortex. These studies have relied heavily on short-term organotypic culture methods and on the analysis of mutant mice that die during the neonatal period. The purpose of this study is to ascertain directly whether cells labeled in the subcortical telencephalon in vivo differentiate into mature cortical interneurons and whether any cortical interneurons arise from the dorsal, cortical neuroepithelium. Mitotic cells within the neonatal cortex or subcortical telencephalon were labeled by focal injections of [(3)H]thymidine into the brains of neonatal ferrets. The fates of labeled cells were assessed in mature animals 6 weeks later. Our results suggest that many cortical interneurons, but not cortical projection neurons, derive from the subcortical telencephalon. Conversely, cortical projection neurons, but few if any interneurons, are generated within the proliferative zones of the neocortex.
Collapse
Affiliation(s)
- Stewart A Anderson
- Department of Psychiatry, University of California at San Francisco, San Francisco, CA, USA.
| | | | | | | | | |
Collapse
|
239
|
Booth V, Bose A. Burst synchrony patterns in hippocampal pyramidal cell model networks. Network 2002; 13:157-177. [PMID: 12061418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Types of. mechanisms for and stability of synchrony are discussed in the context of two-compartment CA3 pyramidal cell and interneuron model networks. We show how the strength and timing of inhibitory and excitatory synaptic inputs work together to produce either perfectly synchronized or nearly synchronized oscillations, across different burst or spiking modes of firing. The analysis shows how excitatory inputs tend to desynchronize cells, and how common, slowly decaying inhibition can be used to synchronize them. We also introduce the concept of 'equivalent networks' in which networks with different architectures and synaptic connections display identical firing patterns.
Collapse
Affiliation(s)
- Victoria Booth
- Department of Mathematical Sciences, Center for Applied Mathematics and Statistics, New Jersey Institute of Technology, Newark 07102-1982, USA.
| | | |
Collapse
|
240
|
Abstract
In the developing spinal cord, signals from the roof plate are required for the development of three classes of dorsal interneuron: D1, D2, and D3, listed from dorsal to ventral. Here, we demonstrate that absence of Wnt1 and Wnt3a, normally expressed in the roof plate, leads to diminished development of D1 and D2 neurons and a compensatory increase in D3 neuron populations. This occurs without significantly altered expression of BMP and related genes in the roof plate. Moreover, Wnt3a protein induces expression of D1 and D2 markers in the isolated medial region of the chick neural plate, and Noggin does not interfere with this induction. Thus, Wnt signaling plays a critical role in the specification of cell types for dorsal interneurons.
Collapse
Affiliation(s)
- Yuko Muroyama
- Kondoh Differentiation Signaling Project, Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology Corporation (JST), Kinki Invention Center, Sakyo-ku, Kyoto 606-8305, Japan
| | | | | | | | | |
Collapse
|
241
|
Abstract
Fast and accurate synaptic transmission requires high-density accumulation of neurotransmitter receptors in the postsynaptic membrane. During development of the neuromuscular junction, clustering of acetylcholine receptors (AChR) is one of the first signs of postsynaptic specialization and is induced by nerve-released agrin. Recent studies have revealed that different mechanisms regulate assembly vs stabilization of AChR clusters and of the postsynaptic apparatus. MuSK, a receptor tyrosine kinase and component of the agrin receptor, and rapsyn, an AChR-associated anchoring protein, play crucial roles in the postsynaptic assembly. Once formed, AChR clusters and the postsynaptic membrane are stabilized by components of the dystrophin/utrophin glycoprotein complex, some of which also direct aspects of synaptic maturation such as formation of postjunctional folds. Nicotinic receptors are also expressed across the peripheral and central nervous system (PNS/CNS). These receptors are localized not only at the pre- but also at the postsynaptic sites where they carry out major synaptic transmission. In neurons, they are found as clusters at synaptic or extrasynaptic sites, suggesting that different mechanisms might underlie this specific localization of nicotinic receptors. This review summarizes the current knowledge about formation and stabilization of the postsynaptic apparatus at the neuromuscular junction and extends this to explore the synaptic structures of interneuronal cholinergic synapses.
Collapse
Affiliation(s)
- Kyung-Hye Huh
- Department of Neurochemistry, Brain Research Institute, University of Zürich, Switzerland
| | | |
Collapse
|
242
|
Abstract
In recent years, studies of molluscan and crustacean feeding circuits have greatly expanded our knowledge of how the nervous system selects specific behaviors. Increasing use of neurobehavioral studies, and examination of the roles of identified command-like or influential neurons have narrowed the gap between knowledge of circuit connectivity and understanding of the normal behavioral functions of these circuits.
Collapse
Affiliation(s)
- I Kupfermann
- Center for Neurobiology and Behavior, College of Physicians and Surgeons of Columbia University, 1051 Riverside Drive, Box 87, New York, NY 10032, USA.
| | | |
Collapse
|
243
|
Delwaide PJ. Parkinsonian rigidity. Funct Neurol 2001; 16:147-56. [PMID: 11495420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Affiliation(s)
- P J Delwaide
- University Department of Neurology, CHR de la Citadelle, Liège, Belgium.
| |
Collapse
|
244
|
Abstract
Antidromic volleys in muscle nerves may facilitate monosynaptic reflexes originating from neighboring motoneurons. This facilitation has been studied in spinal cats. It is at its peak with a conditioning-test interval of 20 to 30 msec., and can last 50 to 100 msec. The threshold of facilitation is about the same as that of recurrent inhibition. Both phenomena appear to be activated by stimulation of the large motor axons. The latency of facilitation seems to be longer than that of recurrent inhibition by approximately 1 msec., suggesting the presence of at least one more synaptic delay. Facilitation often follows an inhibition of variable depth and duration. Frequently, however, the facilitation is not preceded by inhibition, and therefore it cannot be a rebound effect. The pharmacological properties of facilitation resemble those of recurrent inhibition. Dihydro-beta-erythroidine(1) partially blocks facilitation; the peak is decreased and occurs earlier, and the duration is shortened. Eserine increases the duration of facilitation and inhibition and sometimes enhances their magnitude. It is concluded that recurrent facilitation is mediated by the cholinergic axon collaterals, and that at least two interneurons are located between collateral and motoneuron. Possible mechanisms of facilitation are discussed.
Collapse
|
245
|
KOLMODIN GM, SKOGLUND CR. Slow membrane potential changes accompanying excitation and inhibition in spinal moto- and interneurons in the cat during natural activation. ACTA ACUST UNITED AC 2000; 44:11-54. [PMID: 13605806 DOI: 10.1111/j.1748-1716.1958.tb01607.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
246
|
Abstract
1. Phencyclidine (PCP), a non-competitive NMDA-receptor antagonist, is able to induce schizophrenia-like symptoms in animals and in humans. It is known that schizophrenic patients have deficits in memory processes. 2. Therefore, it was investigated whether subchronic pulsatile or continuous application of 5.0 mg kg(-1) PCP over 5 days induce short-term memory deficits in holeboard learning and the action of two different neuroleptics on this behavioural test. 3. First, an impairment in the holeboard task was described when the animals were tested 24 h after the last application but not after 15 min or 1 h after the last injection. Secondly, the influence of haloperidol and risperidone on the PCP-induced short-term memory changes was tested. 4. The combined application of PCP and risperidone led to a complete antagonism of the short-term deficits, but the combined treatment with haloperidol was accompanied by a partial abolishment of the PCP-induced deficits. 5. PCP led to an upregulation of the glutamate binding sites in striatum and nucleus accumbens whereas the D(2) binding sites were reduced in striatum. The D(1) binding sites seem to be unchanged. The receptor protein expression of glutamate receptors mGluR1, GluR2, GluR5/7 and NMDAR1 were not modified in response to PCP treatment. 6. The determination of a subpopulation of GABAergic interneurons shows a decrease of the cells within the CA3 of the hippocampal formation. 7. These findings indicate that PCP induced impairments in short term memory can be detected by holeboard learning and may provide an interesting tool for the search of new neuroleptics.
Collapse
Affiliation(s)
- U Schroeder
- Institute of Medical Psychology, Medical Faculty, Leipziger Str. 44, 39 120 Magdeburg, Germany.
| | | | | | | |
Collapse
|
247
|
Huang ZJ, Kirkwood A, Pizzorusso T, Porciatti V, Morales B, Bear MF, Maffei L, Tonegawa S. BDNF regulates the maturation of inhibition and the critical period of plasticity in mouse visual cortex. Cell 1999; 98:739-55. [PMID: 10499792 DOI: 10.1016/s0092-8674(00)81509-3] [Citation(s) in RCA: 893] [Impact Index Per Article: 35.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Maturation of the visual cortex is influenced by visual experience during an early postnatal period. The factors that regulate such a critical period remain unclear. We examined the maturation and plasticity of the visual cortex in transgenic mice in which the postnatal rise of brain-derived neurotrophic factor (BDNF) was accelerated. In these mice, the maturation of GABAergic innervation and inhibition was accelerated. Furthermore, the age-dependent decline of cortical long-term potentiation induced by white matter stimulation, a form of synaptic plasticity sensitive to cortical inhibition, occurred earlier. Finally, transgenic mice showed a precocious development of visual acuity and an earlier termination of the critical period for ocular dominance plasticity. We propose that BDNF promotes the maturation of cortical inhibition during early postnatal life, thereby regulating the critical period for visual cortical plasticity.
Collapse
Affiliation(s)
- Z J Huang
- Center for Learning and Memory, Department of Biology, Massachusetts Institute of Technology, Cambridge 02139, USA
| | | | | | | | | | | | | | | |
Collapse
|
248
|
Capper-Loup C, Rubin BP, Rager G. Extracellular matrix and development of lamination in the dorsal lateral geniculate nucleus in the tree shrew (Tupaia belangeri). Anat Embryol (Berl) 1999; 199:549-61. [PMID: 10350135 DOI: 10.1007/s004290050252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In the tree shrew (Tupaia belangeri), the cytoarchitectonic lamination of the lateral geniculate nucleus cannot be detected at birth; it only appears during the early postnatal period. However, a laminated pattern was revealed with rapid Golgi staining and retinal afferents were segregated into the appropriate laminae well before cytoarchitectonic lamination could be seen. Both observations indicate that the extracellular matrix may play a role in the separation of lateral geniculate nucleus cells into laminae. In the present study, the organization of the extracellular matrix was investigated during development using immunohistochemical and in situ hybridization techniques. For immunohistochemistry, peanut agglutinin (PNA) lectin and antibodies against tenascin (TN) were chosen, while for in situ hybridization, mTN riboprobes were used, simultaneously, with antibodies against Vimentin (Vim) and microtubule associated protein (MAP-2). The results showed that the pattern of PNA-binding glycoproteins and that of tenascin were relatively similar, although tenascin appeared later and disappeared earlier. The first interlaminar spaces to be detected were those between layers innervated by opposite eyes. The TN specific mRNA was detected in the lateral geniculate nucleus at P0, but was no longer visible at P7. By comparing TN mRNA and Vim or MAP-2 stainings a correspondence could be observed. The extracellular matrix lamination therefore seems to precede cytoarchitectonic lamination, suggesting that the extracellular matrix may play a role in the development of laminated structures. The TN-producing cells seem to be developing astrocytes and neurons.
Collapse
Affiliation(s)
- C Capper-Loup
- Institute of Anatomy, University of Fribourg, Switzerland
| | | | | |
Collapse
|
249
|
Abstract
Synaptic distributions of N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methylisoxazolepropionic acid (AMPA) receptor subunits, NMDAR1 and GluR2, respectively, were examined by electron microscopy with the high spatial resolution of postembedding immunogold localization. We provide direct evidence for colocalization at individual axodendritic asymmetric synapses within the CA1 subfield of rat hippocampus. AMPA/NMDA receptor colocalization was found both in gamma-aminobutyric acid (GABA)ergic dendrites and non-GABAergic dendritic shafts, as well as dendritic spines. Some asymmetric synapses were found to contain only NMDAR1 or GluR2; however, most immunopositive synapses contained both subunits. Many NMDAR1 and/or GluR2 immunopositive profiles received GABAergic innervation at an adjacent synapse, providing a substrate for GABAergic modulation of both GluR classes. These data suggest that excitatory neuronal transmission in CA1 neurons may generally involve activation of both NMDA and AMPA receptor subunits at a single synapse, however, they also offer ultrastructural evidence for NMDAR1-only synapses that might represent silent synapses.
Collapse
Affiliation(s)
- Y He
- Fishberg Research Center for Neurobiology and Neurobiology of Aging Laboratories, Mount Sinai School of Medicine, New York, New York 10029, USA
| | | | | |
Collapse
|
250
|
|