101
|
Lombaert N, Hennes M, Gilissen S, Schevenels G, Aerts L, Vanlaer R, Geenen L, Van Eeckhaut A, Smolders I, Nys J, Arckens L. 5-HTR 2A and 5-HTR 3A but not 5-HTR 1A antagonism impairs the cross-modal reactivation of deprived visual cortex in adulthood. Mol Brain 2018; 11:65. [PMID: 30400993 PMCID: PMC6218970 DOI: 10.1186/s13041-018-0404-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 10/10/2018] [Indexed: 01/03/2023] Open
Abstract
Visual cortical areas show enhanced tactile responses in blind individuals, resulting in improved behavioral performance. Induction of unilateral vision loss in adult mice, by monocular enucleation (ME), is a validated model for such cross-modal brain plasticity. A delayed whisker-driven take-over of the medial monocular zone of the visual cortex is preceded by so-called unimodal plasticity, involving the potentiation of the spared-eye inputs in the binocular cortical territory. Full reactivation of the sensory-deprived contralateral visual cortex is accomplished by 7 weeks post-injury. Serotonin (5-HT) is known to modulate sensory information processing and integration, but its impact on cortical reorganization after sensory loss, remains largely unexplored. To address this issue, we assessed the involvement of 5-HT in ME-induced cross-modal plasticity and the 5-HT receptor (5-HTR) subtype used. We first focused on establishing the impact of ME on the total 5-HT concentration measured in the visual cortex and in the somatosensory barrel field. Next, the changes in expression as a function of post-ME recovery time of the monoamine transporter 2 (vMAT2), which loads 5-HT into presynaptic vesicles, and of the 5-HTR1A and 5-HTR3A were assessed, in order to link these temporal expression profiles to the different types of cortical plasticity induced by ME. In order to accurately pinpoint which 5-HTR exactly mediates ME-induced cross-modal plasticity, we pharmacologically antagonized the 5-HTR1A, 5-HTR2A and 5-HTR3A subtypes. This study reveals brain region-specific alterations in total 5-HT concentration, time-dependent modulations in vMAT2, 5-HTR1A and 5-HTR3A protein expression and 5-HTR antagonist-specific effects on the post-ME plasticity phenomena. Together, our results confirm a role for 5-HTR1A in the early phase of binocular visual cortex plasticity and suggest an involvement of 5-HTR2A and 5-HTR3A but not 5-HTR1A during the late cross-modal recruitment of the medial monocular visual cortex. These insights contribute to the general understanding of 5-HT function in cortical plasticity and may encourage the search for improved rehabilitation strategies to compensate for sensory loss.
Collapse
Affiliation(s)
- Nathalie Lombaert
- Laboratory of Neuroplasticity and Neuroproteomics, Katholieke Universiteit Leuven, Naamsestraat 59, Box 2467, B-3000, Leuven, Belgium
| | - Maroussia Hennes
- Laboratory of Neuroplasticity and Neuroproteomics, Katholieke Universiteit Leuven, Naamsestraat 59, Box 2467, B-3000, Leuven, Belgium
| | - Sara Gilissen
- Laboratory of Neuroplasticity and Neuroproteomics, Katholieke Universiteit Leuven, Naamsestraat 59, Box 2467, B-3000, Leuven, Belgium
| | - Giel Schevenels
- Laboratory of Neuroplasticity and Neuroproteomics, Katholieke Universiteit Leuven, Naamsestraat 59, Box 2467, B-3000, Leuven, Belgium
| | - Laetitia Aerts
- Laboratory of Neuroplasticity and Neuroproteomics, Katholieke Universiteit Leuven, Naamsestraat 59, Box 2467, B-3000, Leuven, Belgium
| | - Ria Vanlaer
- Laboratory of Neuroplasticity and Neuroproteomics, Katholieke Universiteit Leuven, Naamsestraat 59, Box 2467, B-3000, Leuven, Belgium
| | - Lieve Geenen
- Laboratory of Neuroplasticity and Neuroproteomics, Katholieke Universiteit Leuven, Naamsestraat 59, Box 2467, B-3000, Leuven, Belgium
| | - Ann Van Eeckhaut
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Ilse Smolders
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Julie Nys
- Laboratory of Neuroplasticity and Neuroproteomics, Katholieke Universiteit Leuven, Naamsestraat 59, Box 2467, B-3000, Leuven, Belgium.,Present Address: Laboratory of Synapse Biology, VIB-KU Leuven Center for Brain and Disease Research, O&N IV, Herestraat 49, box 602, B-3000, Leuven, Belgium
| | - Lutgarde Arckens
- Laboratory of Neuroplasticity and Neuroproteomics, Katholieke Universiteit Leuven, Naamsestraat 59, Box 2467, B-3000, Leuven, Belgium.
| |
Collapse
|
102
|
Bockhorst T, Pieper F, Engler G, Stieglitz T, Galindo-Leon E, Engel AK. Synchrony surfacing: Epicortical recording of correlated action potentials. Eur J Neurosci 2018; 48:3583-3596. [DOI: 10.1111/ejn.14167] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Revised: 08/31/2018] [Accepted: 09/18/2018] [Indexed: 12/31/2022]
Affiliation(s)
- Tobias Bockhorst
- Department of Neurophysiology and Pathophysiology; University Medical Center Hamburg-Eppendorf; Hamburg Germany
| | - Florian Pieper
- Department of Neurophysiology and Pathophysiology; University Medical Center Hamburg-Eppendorf; Hamburg Germany
| | - Gerhard Engler
- Department of Neurophysiology and Pathophysiology; University Medical Center Hamburg-Eppendorf; Hamburg Germany
| | - Thomas Stieglitz
- Department of Microsystems Engineering -IMTEK; Laboratory for Biomedical Microsystems; Albert-Ludwig-University of Freiburg; Freiburg Germany
- BrainLinks-BrainTools; Albert-Ludwig-University of Freiburg; Freiburg Germany
- Bernstein Center Freiburg; Albert-Ludwig-University of Freiburg; Freiburg Germany
| | - Edgar Galindo-Leon
- Department of Neurophysiology and Pathophysiology; University Medical Center Hamburg-Eppendorf; Hamburg Germany
| | - Andreas K. Engel
- Department of Neurophysiology and Pathophysiology; University Medical Center Hamburg-Eppendorf; Hamburg Germany
| |
Collapse
|
103
|
Learning-Related Plasticity in Dendrite-Targeting Layer 1 Interneurons. Neuron 2018; 100:684-699.e6. [PMID: 30269988 PMCID: PMC6226614 DOI: 10.1016/j.neuron.2018.09.001] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 08/09/2018] [Accepted: 08/31/2018] [Indexed: 11/23/2022]
Abstract
A wealth of data has elucidated the mechanisms by which sensory inputs are encoded in the neocortex, but how these processes are regulated by the behavioral relevance of sensory information is less understood. Here, we focus on neocortical layer 1 (L1), a key location for processing of such top-down information. Using Neuron-Derived Neurotrophic Factor (NDNF) as a selective marker of L1 interneurons (INs) and in vivo 2-photon calcium imaging, electrophysiology, viral tracing, optogenetics, and associative memory, we find that L1 NDNF-INs mediate a prolonged form of inhibition in distal pyramidal neuron dendrites that correlates with the strength of the memory trace. Conversely, inhibition from Martinotti cells remains unchanged after conditioning but in turn tightly controls sensory responses in NDNF-INs. These results define a genetically addressable form of dendritic inhibition that is highly experience dependent and indicate that in addition to disinhibition, salient stimuli are encoded at elevated levels of distal dendritic inhibition. Video Abstract
NDNF is a selective marker for neocortical layer 1 interneurons NDNF interneurons mediate prolonged inhibition of distal pyramidal neuron dendrites Inhibition from Martinotti cells tightly controls NDNF interneuron responses Dendritic inhibition by NDNF interneurons is highly experience dependent
Collapse
|
104
|
Zingg B, Dong HW, Tao HW, Zhang LI. Input-output organization of the mouse claustrum. J Comp Neurol 2018; 526:2428-2443. [PMID: 30252130 DOI: 10.1002/cne.24502] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/27/2018] [Accepted: 06/28/2018] [Indexed: 01/04/2023]
Abstract
Progress in determining the precise organization and function of the claustrum (CLA) has been hindered by the difficulty in reliably targeting these neurons. To overcome this, we used a projection-based targeting strategy to selectively label CLA principal neurons. Combined with adeno-associated virus (AAV) and monosynaptic rabies tracing techniques, we systematically examined the pre-synaptic input and axonal output of this structure. We found that CLA neurons projecting to retrosplenial cortex (RSP) collateralize extensively to innervate a variety of higher-order cortical regions. No subcortical labeling was found, with the exception of sparse terminals in the basolateral amygdala (BLA). This pattern of output was similar to cingulate- and visual cortex-projecting CLA neurons, suggesting a common targeting scheme among these projection-defined populations. Rabies virus tracing directly demonstrated widespread synaptic inputs to RSP-projecting CLA neurons from both cortical and subcortical areas. The strongest inputs arose from classically defined limbic regions, including medial prefrontal cortex, anterior cingulate, BLA, ventral hippocampus, and neuromodulatory systems such as the dorsal raphe and cholinergic basal forebrain. These results suggest that the CLA may integrate information related to the emotional salience of stimuli and may globally modulate cortical state by broadcasting its output uniformly across a variety of higher cognitive centers.
Collapse
Affiliation(s)
- Brian Zingg
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California.,Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California.,Neuroscience Graduate Program, University of Southern California, Los Angeles, California
| | - Hong-Wei Dong
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California.,Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Huizhong Whit Tao
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California.,Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Li I Zhang
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California.,Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California
| |
Collapse
|
105
|
Izquierdo-Serra M, Hirtz JJ, Shababo B, Yuste R. Two-Photon Optogenetic Mapping of Excitatory Synaptic Connectivity and Strength. iScience 2018; 8:15-28. [PMID: 30268510 PMCID: PMC6170329 DOI: 10.1016/j.isci.2018.09.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 07/27/2018] [Accepted: 09/07/2018] [Indexed: 11/18/2022] Open
Abstract
The development of optical methods to activate neurons with single-cell resolution has enabled systematic mapping of inhibitory connections. In contrast, optical mapping of excitatory connections between pyramidal neurons (PCs) has been a major challenge due to their high densities in cortical tissue and their weak and stochastic connectivity. Here we present an optogenetic two-photon mapping method in mouse neocortical slices by activating PCs with the red-shifted opsin C1V1 while recording postsynaptic responses in whole-cell configuration. Comparison of delays from triggered action potentials (APs) with those from synaptic inputs allowed us to predict connected PCs in three dimensions. We confirmed these predictions with paired recordings, and used this method to map strong connections among large populations of layer 2/3 PCs. Our method can be used for fast, systematic mapping of synaptic connectivity and weights. Two-photon optogenetic mapping of excitatory connectivity and strength in neocortex Identification of connected neurons in acute slices through numerical optimization Synaptic delays align with location of connected presynaptic cell Confirmation of predicted connections by dual patch-clamp recordings
Collapse
Affiliation(s)
- Mercè Izquierdo-Serra
- NeuroTechnology Center, Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
| | - Jan J Hirtz
- NeuroTechnology Center, Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
| | - Ben Shababo
- NeuroTechnology Center, Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Rafael Yuste
- NeuroTechnology Center, Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| |
Collapse
|
106
|
Preferential inputs from cholecystokinin-positive neurons to the somatic compartment of parvalbumin-expressing neurons in the mouse primary somatosensory cortex. Brain Res 2018; 1695:18-30. [DOI: 10.1016/j.brainres.2018.05.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 05/10/2018] [Accepted: 05/19/2018] [Indexed: 12/22/2022]
|
107
|
Chevée M, Brown SP. The development of local circuits in the neocortex: recent lessons from the mouse visual cortex. Curr Opin Neurobiol 2018; 53:103-109. [PMID: 30053693 DOI: 10.1016/j.conb.2018.06.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 06/14/2018] [Accepted: 06/14/2018] [Indexed: 12/26/2022]
Abstract
Precise synaptic connections among neurons in the neocortex generate the circuits that underlie a broad repertoire of cortical functions including perception, learning and memory, and complex problem solving. The specific patterns and properties of these synaptic connections are fundamental to the computations cortical neurons perform. How such specificity arises in cortical circuits has remained elusive. Here, we first consider the cell-type, subcellular and synaptic specificity required for generating mature patterns of cortical connectivity and responses. Next, we focus on recent progress in understanding how the synaptic connections among excitatory cortical projection neurons are established during development using the primary visual cortex of the mouse as a model.
Collapse
Affiliation(s)
- Maxime Chevée
- Biochemistry, Cellular and Molecular Biology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Solange P Brown
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| |
Collapse
|
108
|
Che A, Babij R, Iannone AF, Fetcho RN, Ferrer M, Liston C, Fishell G, De Marco García NV. Layer I Interneurons Sharpen Sensory Maps during Neonatal Development. Neuron 2018; 99:98-116.e7. [PMID: 29937280 PMCID: PMC6152945 DOI: 10.1016/j.neuron.2018.06.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 04/26/2018] [Accepted: 06/01/2018] [Indexed: 12/26/2022]
Abstract
The neonatal mammal faces an array of sensory stimuli when diverse neuronal types have yet to form sensory maps. How these inputs interact with intrinsic neuronal activity to facilitate circuit assembly is not well understood. By using longitudinal calcium imaging in unanesthetized mouse pups, we show that layer I (LI) interneurons, delineated by co-expression of the 5HT3a serotonin receptor (5HT3aR) and reelin (Re), display spontaneous calcium transients with the highest degree of synchrony among cell types present in the superficial barrel cortex at postnatal day 6 (P6). 5HT3aR Re interneurons are activated by whisker stimulation during this period, and sensory deprivation induces decorrelation of their activity. Moreover, attenuation of thalamic inputs through knockdown of NMDA receptors (NMDARs) in these interneurons results in expansion of whisker responses, aberrant barrel map formation, and deficits in whisker-dependent behavior. These results indicate that recruitment of specific interneuron types during development is critical for adult somatosensory function. VIDEO ABSTRACT.
Collapse
Affiliation(s)
- Alicia Che
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10021, USA
| | - Rachel Babij
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10021, USA; Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, New York, NY 10021, USA
| | - Andrew F Iannone
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10021, USA; Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, New York, NY 10021, USA
| | - Robert N Fetcho
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10021, USA; Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, New York, NY 10021, USA
| | - Monica Ferrer
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10021, USA
| | - Conor Liston
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10021, USA
| | - Gord Fishell
- Harvard Medical School and the Stanley Center at the Broad, Cambridge, MA 02142, USA
| | - Natalia V De Marco García
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10021, USA.
| |
Collapse
|
109
|
Zhou X, Rickmann M, Hafner G, Staiger JF. Subcellular Targeting of VIP Boutons in Mouse Barrel Cortex is Layer-Dependent and not Restricted to Interneurons. Cereb Cortex 2018; 27:5353-5368. [PMID: 28968722 PMCID: PMC6084601 DOI: 10.1093/cercor/bhx220] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Accepted: 08/02/2017] [Indexed: 12/22/2022] Open
Abstract
Neocortical vasoactive intestinal polypeptide (VIP) expressing cells are a diverse subpopulation of GABAergic interneurons issuing distinct axonal projections. They are known to inhibit other types of interneurons as well as excitatory principal neurons and possess a disinhibitory net effect in cortical circuits. In order to elucidate their targeting specificity, the output connectivity of VIP interneurons was studied at the subcellular level in barrel cortex of interneuron-specific Cre-driver mice, using pre- and postembedding electron microscopy. Systematically sampling VIP boutons across all layers, we found a substantial proportion of the innervated subcellular structures were dendrites (80%), with somata (13%), and spines (7%) being much less targeted. In layer VI, a high proportion of axosomatic synapses was found (39%). GABA-immunopositive ratio was quantified among the targets using statistically validated thresholds: only 37% of the dendrites, 7% of the spines, and 26% of the somata showed above-threshold immunogold labeling. For the main target structure "dendrite", a higher proportion of GABAergic subcellular profiles existed in deep than in superficial layers. In conclusion, VIP interneurons innervate non-GABAergic excitatory neurons and interneurons at their subcellular domains with layer-dependent specificity. This suggests a diverse output of VIP interneurons, which predicts multiple functionality in cortical circuitry beyond disinhibition.
Collapse
Affiliation(s)
- Xiaojuan Zhou
- Institute for Neuroanatomy,University Medicine Göttingen, Georg-August-University, Kreuzbergring 36, D-37075 Göttingen, Germany
| | - Michael Rickmann
- Institute for Neuroanatomy,University Medicine Göttingen, Georg-August-University, Kreuzbergring 36, D-37075 Göttingen, Germany
| | - Georg Hafner
- Institute for Neuroanatomy,University Medicine Göttingen, Georg-August-University, Kreuzbergring 36, D-37075 Göttingen, Germany
| | - Jochen F Staiger
- Institute for Neuroanatomy,University Medicine Göttingen, Georg-August-University, Kreuzbergring 36, D-37075 Göttingen, Germany
| |
Collapse
|
110
|
Garcia LP, Witteveen JS, Middelman A, van Hulten JA, Martens GJM, Homberg JR, Kolk SM. Perturbed Developmental Serotonin Signaling Affects Prefrontal Catecholaminergic Innervation and Cortical Integrity. Mol Neurobiol 2018; 56:1405-1420. [PMID: 29948943 PMCID: PMC6400880 DOI: 10.1007/s12035-018-1105-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 05/03/2018] [Indexed: 11/26/2022]
Abstract
Proper development of the medial prefrontal cortex (mPFC), crucial for correct cognitive functioning, requires projections from, among others, the serotonergic (5-HT) and catecholaminergic systems, but it is unclear how these systems influence each other during development. Here, we describe the parallel development of the 5-HT and catecholaminergic prefrontal projection systems in rat and demonstrate a close engagement of both systems in the proximity of Cajal-Retzius cells. We further show that in the absence of the 5-HT transporter (5-HTT), not only the developing 5-HT but also the catecholaminergic system, including their projections towards the mPFC, are affected. In addition, the layer identity of the mPFC neurons and reelin-positive interneuron number and integration are altered in the absence of the 5-HTT. Together, our data demonstrate a functional interplay between the developing mPFC 5-HT and catecholaminergic systems, and call for a holistic approach in studying neurotransmitter systems-specific developmental consequences for adult behavior, to eventually allow the design of better treatment strategies for neuropsychiatric disorders.
Collapse
Affiliation(s)
- Lidiane P Garcia
- Donders Institute for Brain, Cognition, and Behaviour, Centre for Neuroscience, Department of Molecular Animal Physiology, Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Nijmegen, Geert Grooteplein Zuid 28, 6525 GA, Nijmegen, The Netherlands
| | - Josefine S Witteveen
- Donders Institute for Brain, Cognition, and Behaviour, Centre for Neuroscience, Department of Molecular Animal Physiology, Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Nijmegen, Geert Grooteplein Zuid 28, 6525 GA, Nijmegen, The Netherlands
| | - Anthonieke Middelman
- Donders Institute for Brain, Cognition, and Behaviour, Centre for Neuroscience, Department of Cognitive Neuroscience, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Josephus A van Hulten
- Donders Institute for Brain, Cognition, and Behaviour, Centre for Neuroscience, Department of Molecular Animal Physiology, Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Nijmegen, Geert Grooteplein Zuid 28, 6525 GA, Nijmegen, The Netherlands
| | - Gerard J M Martens
- Donders Institute for Brain, Cognition, and Behaviour, Centre for Neuroscience, Department of Molecular Animal Physiology, Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Nijmegen, Geert Grooteplein Zuid 28, 6525 GA, Nijmegen, The Netherlands
| | - Judith R Homberg
- Donders Institute for Brain, Cognition, and Behaviour, Centre for Neuroscience, Department of Cognitive Neuroscience, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Sharon M Kolk
- Donders Institute for Brain, Cognition, and Behaviour, Centre for Neuroscience, Department of Molecular Animal Physiology, Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Nijmegen, Geert Grooteplein Zuid 28, 6525 GA, Nijmegen, The Netherlands.
| |
Collapse
|
111
|
Harris KD, Hochgerner H, Skene NG, Magno L, Katona L, Bengtsson Gonzales C, Somogyi P, Kessaris N, Linnarsson S, Hjerling-Leffler J. Classes and continua of hippocampal CA1 inhibitory neurons revealed by single-cell transcriptomics. PLoS Biol 2018; 16:e2006387. [PMID: 29912866 PMCID: PMC6029811 DOI: 10.1371/journal.pbio.2006387] [Citation(s) in RCA: 168] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 07/03/2018] [Accepted: 05/22/2018] [Indexed: 01/19/2023] Open
Abstract
Understanding any brain circuit will require a categorization of its constituent neurons. In hippocampal area CA1, at least 23 classes of GABAergic neuron have been proposed to date. However, this list may be incomplete; additionally, it is unclear whether discrete classes are sufficient to describe the diversity of cortical inhibitory neurons or whether continuous modes of variability are also required. We studied the transcriptomes of 3,663 CA1 inhibitory cells, revealing 10 major GABAergic groups that divided into 49 fine-scale clusters. All previously described and several novel cell classes were identified, with three previously described classes unexpectedly found to be identical. A division into discrete classes, however, was not sufficient to describe the diversity of these cells, as continuous variation also occurred between and within classes. Latent factor analysis revealed that a single continuous variable could predict the expression levels of several genes, which correlated similarly with it across multiple cell types. Analysis of the genes correlating with this variable suggested it reflects a range from metabolically highly active faster-spiking cells that proximally target pyramidal cells to slower-spiking cells targeting distal dendrites or interneurons. These results elucidate the complexity of inhibitory neurons in one of the simplest cortical structures and show that characterizing these cells requires continuous modes of variation as well as discrete cell classes.
Collapse
Affiliation(s)
- Kenneth D. Harris
- University College London Institute of Neurology, London, United Kingdom
- University College London Department of Neuroscience, Physiology and Pharmacology, London, United Kingdom
| | - Hannah Hochgerner
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Nathan G. Skene
- University College London Institute of Neurology, London, United Kingdom
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Lorenza Magno
- University College London Wolfson Institute for Biomedical Research, London, United Kingdom
| | - Linda Katona
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Carolina Bengtsson Gonzales
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Peter Somogyi
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Nicoletta Kessaris
- University College London Wolfson Institute for Biomedical Research, London, United Kingdom
| | - Sten Linnarsson
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Jens Hjerling-Leffler
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|
112
|
Rutishauser U, Slotine JJ, Douglas RJ. Solving Constraint-Satisfaction Problems with Distributed Neocortical-Like Neuronal Networks. Neural Comput 2018; 30:1359-1393. [PMID: 29566357 PMCID: PMC5930080 DOI: 10.1162/neco_a_01074] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Finding actions that satisfy the constraints imposed by both external inputs and internal representations is central to decision making. We demonstrate that some important classes of constraint satisfaction problems (CSPs) can be solved by networks composed of homogeneous cooperative-competitive modules that have connectivity similar to motifs observed in the superficial layers of neocortex. The winner-take-all modules are sparsely coupled by programming neurons that embed the constraints onto the otherwise homogeneous modular computational substrate. We show rules that embed any instance of the CSP's planar four-color graph coloring, maximum independent set, and sudoku on this substrate and provide mathematical proofs that guarantee these graph coloring problems will convergence to a solution. The network is composed of nonsaturating linear threshold neurons. Their lack of right saturation allows the overall network to explore the problem space driven through the unstable dynamics generated by recurrent excitation. The direction of exploration is steered by the constraint neurons. While many problems can be solved using only linear inhibitory constraints, network performance on hard problems benefits significantly when these negative constraints are implemented by nonlinear multiplicative inhibition. Overall, our results demonstrate the importance of instability rather than stability in network computation and offer insight into the computational role of dual inhibitory mechanisms in neural circuits.
Collapse
Affiliation(s)
- Ueli Rutishauser
- Computation and Neural Systems, Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, U.S.A., and Cedars-Sinai Medical Center, Departments of Neurosurgery, Neurology and Biomedical Sciences, Los Angeles, CA 90048, U.S.A.
| | - Jean-Jacques Slotine
- Nonlinear Systems Laboratory, Department of Mechanical Engineering and Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, U.S.A.
| | - Rodney J Douglas
- Institute of Neuroinformatics, University and ETH Zurich, Zurich 8057, Switzerland
| |
Collapse
|
113
|
Altered Excitability and Local Connectivity of mPFC-PAG Neurons in a Mouse Model of Neuropathic Pain. J Neurosci 2018; 38:4829-4839. [PMID: 29695413 DOI: 10.1523/jneurosci.2731-17.2018] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 03/09/2018] [Accepted: 03/20/2018] [Indexed: 12/29/2022] Open
Abstract
The medial prefrontal cortex (mPFC) plays a major role in both sensory and affective aspects of pain. There is extensive evidence that chronic pain produces functional changes within the mPFC. However, our understanding of local circuit changes to defined subpopulations of mPFC neurons in chronic pain models remains unclear. A major subpopulation of mPFC neurons project to the periaqueductal gray (PAG), which is a key midbrain structure involved in endogenous pain suppression and facilitation. Here, we used laser scanning photostimulation of caged glutamate to map cortical circuits of retrogradely labeled cortico-PAG (CP) neurons in layer 5 (L5) of mPFC in brain slices prepared from male mice having undergone chronic constriction injury (CCI) of the sciatic nerve. Whole-cell recordings revealed a significant reduction in excitability for L5 CP neurons contralateral to CCI in the prelimbic (PL), but not infralimbic (IL), region of mPFC. Circuit mapping showed that excitatory inputs to L5 CP neurons in both PL and IL arose primarily from layer 2/3 (L2/3) and were significantly reduced in CCI mice. Glutamate stimulation of L2/3 and L5 elicited inhibitory inputs to CP neurons in both PL and IL, but only L2/3 input was significantly reduced in CP neurons of CCI mice. We also observed significant reduction in excitability and L2/3 inhibitory input to CP neurons ipsilateral to CCI. These results demonstrating region and laminar specific changes to mPFC-PAG neurons suggest that a unilateral CCI bilaterally alters cortical circuits upstream of the endogenous analgesic network, which may contribute to persistence of chronic pain.SIGNIFICANCE STATEMENT Chronic pain is a significant unresolved medical problem that is refractory to traditional analgesics and can negatively affect emotional health. The role of central circuits in mediating the persistent nature of chronic pain remains unclear. Local circuits within the medial prefrontal cortex (mPFC) process ascending pain inputs and can modulate endogenous analgesia via direct projections to the periaqueductal gray (PAG). However, the mechanisms by which chronic pain alters intracortical circuitry of mPFC-PAG neurons are unknown. Here, we report specific changes to local circuits of mPFC-PAG neurons in mice displaying chronic pain behavior after nerve injury. These findings provide evidence for a neural mechanism by which chronic pain disrupts the descending analgesic system via functional changes to cortical circuits.
Collapse
|
114
|
Jouhanneau JS, Kremkow J, Poulet JFA. Single synaptic inputs drive high-precision action potentials in parvalbumin expressing GABA-ergic cortical neurons in vivo. Nat Commun 2018; 9:1540. [PMID: 29670095 PMCID: PMC5906477 DOI: 10.1038/s41467-018-03995-2] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 03/23/2018] [Indexed: 01/15/2023] Open
Abstract
A defining feature of cortical layer 2/3 excitatory neurons is their sparse activity, often firing in singlets of action potentials. Local inhibitory neurons are thought to play a major role in regulating sparseness, but which cell types are recruited by single excitatory synaptic inputs is unknown. Using multiple, targeted, in vivo whole-cell recordings, we show that single uEPSPs have little effect on the firing rates of excitatory neurons and somatostatin-expressing GABA-ergic inhibitory neurons but evoke precisely timed action potentials in parvalbumin-expressing inhibitory neurons. Despite a uEPSP decay time of 7.8 ms, the evoked action potentials were almost completely restricted to the uEPSP rising phase (~0.5 ms). Evoked parvalbumin-expressing neuron action potentials go on to inhibit the local excitatory network, thus providing a pathway for single spike evoked disynaptic inhibition which may enforce sparse and precisely timed cortical signaling.
Collapse
Affiliation(s)
- Jean-Sébastien Jouhanneau
- Department of Neuroscience, Max Delbrück Center for Molecular Medicine (MDC), 13125, Berlin-Buch, Germany.,Neuroscience Research Center and Cluster of Excellence NeuroCure, Charité-Universitätsmedizin Berlin, 10117, Berlin, Germany
| | - Jens Kremkow
- Department of Neuroscience, Max Delbrück Center for Molecular Medicine (MDC), 13125, Berlin-Buch, Germany.,Neuroscience Research Center and Cluster of Excellence NeuroCure, Charité-Universitätsmedizin Berlin, 10117, Berlin, Germany.,Department of Biology, Institute for Theoretical Biology, Humboldt-Universität zu Berlin, Philippstrasse 13, 10115, Berlin, Germany
| | - James F A Poulet
- Department of Neuroscience, Max Delbrück Center for Molecular Medicine (MDC), 13125, Berlin-Buch, Germany. .,Neuroscience Research Center and Cluster of Excellence NeuroCure, Charité-Universitätsmedizin Berlin, 10117, Berlin, Germany.
| |
Collapse
|
115
|
The functional organization of cortical feedback inputs to primary visual cortex. Nat Neurosci 2018; 21:757-764. [PMID: 29662217 DOI: 10.1038/s41593-018-0135-z] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 03/06/2018] [Indexed: 11/08/2022]
Abstract
Cortical feedback is thought to mediate cognitive processes like attention, prediction, and awareness. Understanding its function requires identifying the organizational logic of feedback axons relaying different signals. We measured retinotopic specificity in inputs from the lateromedial visual area in mouse primary visual cortex (V1) by mapping receptive fields in feedback boutons and relating them to those of neurons in their vicinity. Lateromedial visual area inputs in layer 1 targeted, on average, retinotopically matched locations in V1, but many of them relayed distal visual information. Orientation-selective axons overspread around the retinotopically matched location perpendicularly to their preferred orientation. Direction-selective axons were biased to visual areas shifted from the retinotopically matched position along the angle of their antipreferred direction. Our results show that feedback inputs show tuning-dependent retinotopic specificity. By targeting locations that would be activated by stimuli orthogonal to or opposite to a cell's own tuning, feedback could potentially enhance visual representations in time and space.
Collapse
|
116
|
Audette NJ, Urban-Ciecko J, Matsushita M, Barth AL. POm Thalamocortical Input Drives Layer-Specific Microcircuits in Somatosensory Cortex. Cereb Cortex 2018; 28:1312-1328. [PMID: 28334225 PMCID: PMC6093433 DOI: 10.1093/cercor/bhx044] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 02/03/2017] [Indexed: 12/11/2022] Open
Abstract
Higher-order thalamic nuclei, such as the posterior medial nucleus (POm) in the somatosensory system or the pulvinar in the visual system, densely innervate the cortex and can influence perception and plasticity. To systematically evaluate how higher-order thalamic nuclei can drive cortical circuits, we investigated cell-type selective responses to POm stimulation in mouse primary somatosensory (barrel) cortex, using genetically targeted whole-cell recordings in acute brain slices. We find that ChR2-evoked thalamic input selectively targets specific cell types in the neocortex, revealing layer-specific modules for the summation and processing of POm input. Evoked activity in pyramidal neurons from deep layers is fast and synchronized by rapid feedforward inhibition from GABAergic parvalbumin-expressing neurons, and activity in superficial layers is weaker and prolonged, facilitated by slow inhibition from GABAergic neurons expressing the 5HT3a receptor. Somatostatin-expressing GABAergic neurons do not receive direct input in either layer and their spontaneous activity is suppressed during POm stimulation. This novel pattern of weak, delayed, thalamus-evoked inhibition in layer 2 suggests a longer integration window for incoming sensory information and may facilitate stimulus detection and plasticity in superficial pyramidal neurons.
Collapse
Affiliation(s)
- Nicholas J Audette
- Department of Biological Sciences and Center for the Neural Basis of Cognition, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, USA
| | - Joanna Urban-Ciecko
- Department of Biological Sciences and Center for the Neural Basis of Cognition, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, USA
| | - Megumi Matsushita
- Department of Biological Sciences and Center for the Neural Basis of Cognition, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, USA
| | - Alison L Barth
- Department of Biological Sciences and Center for the Neural Basis of Cognition, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, USA
| |
Collapse
|
117
|
Guerra A, Suppa A, Bologna M, D'Onofrio V, Bianchini E, Brown P, Di Lazzaro V, Berardelli A. Boosting the LTP-like plasticity effect of intermittent theta-burst stimulation using gamma transcranial alternating current stimulation. Brain Stimul 2018; 11:734-742. [PMID: 29615367 DOI: 10.1016/j.brs.2018.03.015] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 02/27/2018] [Accepted: 03/22/2018] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Transcranial Alternating Current Stimulation (tACS) consists in delivering electric current to the brain using an oscillatory pattern that may entrain the rhythmic activity of cortical neurons. When delivered at gamma frequency, tACS modulates motor performance and GABA-A-ergic interneuron activity. OBJECTIVE Since interneuronal discharges play a crucial role in brain plasticity phenomena, here we co-stimulated the primary motor cortex (M1) in healthy subjects by means of tACS during intermittent theta-burst stimulation (iTBS), a transcranial magnetic stimulation paradigm known to induce long-term potentiation (LTP)-like plasticity. METHODS We measured and compared motor evoked potentials before and after gamma, beta and sham tACS-iTBS. While we delivered gamma-tACS, we also measured short-interval intracortical inhibition (SICI) to detect any changes in GABA-A-ergic neurotransmission. RESULTS Gamma, but not beta and sham tACS, significantly boosted and prolonged the iTBS-induced after-effects. Interestingly, the extent of the gamma tACS-iTBS after-effects correlated directly with SICI changes. CONCLUSIONS Overall, our findings point to a link between gamma oscillations, interneuronal GABA-A-ergic activity and LTP-like plasticity in the human M1. Gamma tACS-iTBS co-stimulation might represent a new strategy to enhance and prolong responses to plasticity-inducing protocols, thereby lending itself to future applications in the neurorehabilitation setting.
Collapse
Affiliation(s)
- Andrea Guerra
- Department of Human Neuroscience, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy
| | - Antonio Suppa
- Department of Human Neuroscience, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy; IRCCS Neuromed Institute, Via Atinense 18, 86077, Pozzilli, IS, Italy
| | - Matteo Bologna
- Department of Human Neuroscience, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy; IRCCS Neuromed Institute, Via Atinense 18, 86077, Pozzilli, IS, Italy
| | - Valentina D'Onofrio
- Department of Human Neuroscience, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy
| | - Edoardo Bianchini
- Department of Human Neuroscience, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy
| | - Peter Brown
- Medical Research Council Brain Network Dynamics Unit and Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU, United Kingdom
| | - Vincenzo Di Lazzaro
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, University Campus Bio-Medico, via Álvaro del Portillo 21, 00128, Rome, Italy
| | - Alfredo Berardelli
- Department of Human Neuroscience, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy; IRCCS Neuromed Institute, Via Atinense 18, 86077, Pozzilli, IS, Italy.
| |
Collapse
|
118
|
Niquille M, Limoni G, Markopoulos F, Cadilhac C, Prados J, Holtmaat A, Dayer A. Neurogliaform cortical interneurons derive from cells in the preoptic area. eLife 2018; 7:32017. [PMID: 29557780 PMCID: PMC5860868 DOI: 10.7554/elife.32017] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 02/21/2018] [Indexed: 12/18/2022] Open
Abstract
Delineating the basic cellular components of cortical inhibitory circuits remains a fundamental issue in order to understand their specific contributions to microcircuit function. It is still unclear how current classifications of cortical interneuron subtypes relate to biological processes such as their developmental specification. Here we identified the developmental trajectory of neurogliaform cells (NGCs), the main effectors of a powerful inhibitory motif recruited by long-range connections. Using in vivo genetic lineage-tracing in mice, we report that NGCs originate from a specific pool of 5-HT3AR-expressing Hmx3+ cells located in the preoptic area (POA). Hmx3-derived 5-HT3AR+ cortical interneurons (INs) expressed the transcription factors PROX1, NR2F2, the marker reelin but not VIP and exhibited the molecular, morphological and electrophysiological profile of NGCs. Overall, these results indicate that NGCs are a distinct class of INs with a unique developmental trajectory and open the possibility to study their specific functional contribution to cortical inhibitory microcircuit motifs. Our brain contains over a 100 billion nerve cells or neurons, and each of them is thought to connect to over 1,000 other neurons. Together, these cells form a complex network to convey information from our surroundings or transmit messages to designated destinations. This circuitry forms the basis of our unique cognitive abilities. In the cerebral cortex – the largest region of the brain – two main types of neurons can be found: projection neurons, which transfer information to other regions in the brain, and interneurons, which connect locally to different neurons and harmonize this information by inhibiting specific messages. The over 20 different types of known interneurons come in different shapes and properties and are thought to play a key role in powerful computations such as learning and memory. Since interneurons are hard to track, it is still unclear when and how they start to form and mature as the brain of an embryo develops. For example, one type of interneurons called the neurogliaform cells, have a very distinct shape and properties. But, until now, the origin of this cell type had been unknown. To find out how neurogliaform cells develop, Niquille, Limoni, Markopoulos et al. used a specific gene called Hmx3 to track these cells over time. With this strategy, the shapes and properties of the cells could be analyzed. The results showed that neurogliaform cells originate from a region outside of the cerebral cortex called the preoptic area, and later travel over long distances to reach their final location. The cells reach the cortex a few days after their birth and take several weeks to mature. These results suggest that the traits of a specific type of neuron is determined very early in life. By labeling this unique subset of interneurons, researchers will now be able to identify the specific molecular mechanisms that help the neurogliaform cells to develop. Furthermore, it will provide a new strategy to fully understand what role these cells play in processing information and guiding behavior.
Collapse
Affiliation(s)
- Mathieu Niquille
- Department of Psychiatry, University of Geneva, Geneva, Switzerland.,Department of Basic Neuroscience, University of Geneva, Geneva, Switzerland
| | - Greta Limoni
- Department of Psychiatry, University of Geneva, Geneva, Switzerland.,Department of Basic Neuroscience, University of Geneva, Geneva, Switzerland
| | - Foivos Markopoulos
- Department of Basic Neuroscience, University of Geneva, Geneva, Switzerland
| | - Christelle Cadilhac
- Department of Psychiatry, University of Geneva, Geneva, Switzerland.,Department of Basic Neuroscience, University of Geneva, Geneva, Switzerland
| | - Julien Prados
- Department of Psychiatry, University of Geneva, Geneva, Switzerland.,Department of Basic Neuroscience, University of Geneva, Geneva, Switzerland
| | - Anthony Holtmaat
- Department of Basic Neuroscience, University of Geneva, Geneva, Switzerland
| | - Alexandre Dayer
- Department of Psychiatry, University of Geneva, Geneva, Switzerland.,Department of Basic Neuroscience, University of Geneva, Geneva, Switzerland
| |
Collapse
|
119
|
Target selectivity of septal cholinergic neurons in the medial and lateral entorhinal cortex. Proc Natl Acad Sci U S A 2018; 115:E2644-E2652. [PMID: 29487212 PMCID: PMC5856533 DOI: 10.1073/pnas.1716531115] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Acetylcholine is a key modulator of hippocampal and entorhinal cortex (EC) function. The majority of cholinergic projections targeting these structures originate in the basal forebrain complex, specifically the medial septum. Many studies focused on the behavioral effects involving these projections, but there still is a paucity regarding their connectivity in the target area. Here we provide this missing link. By combining optogenetics with whole-cell recordings in superficial EC layers, we identified the synaptic target cells of septal cholinergic neurons. This level of analysis is an important step toward a better understanding of the modulatory action of acetylcholine in EC in vivo. The entorhinal cortex (EC) plays a pivotal role in processing and conveying spatial information to the hippocampus. It has long been known that EC neurons are modulated by cholinergic input from the medial septum. However, little is known as to how synaptic release of acetylcholine affects the different cell types in EC. Here we combined optogenetics and patch-clamp recordings to study the effect of cholinergic axon stimulation on distinct neurons in EC. We found dense cholinergic innervations that terminate in layer I and II (LI and LII). Light-activated stimulation of septal cholinergic projections revealed differential responses in excitatory and inhibitory neurons in LI and LII of both medial and lateral EC. We observed depolarizing responses mediated by nicotinic and muscarinic receptors primarily in putative serotonin receptor (p5HT3R)-expressing interneurons. Hyperpolarizing muscarinic receptor-mediated responses were found predominantly in excitatory cells. Additionally, some excitatory as well as a higher fraction of inhibitory neurons received mono- and/or polysynaptic GABAergic inputs, revealing that medial septum cholinergic neurons have the capacity to corelease GABA alongside acetylcholine. Notably, the synaptic effects of acetylcholine were similar in neurons of both medial and lateral EC. Taken together, our findings demonstrate that EC activity may be differentially modulated via the activation or the suppression of distinct subsets of LI and LII neurons by the septal cholinergic system.
Collapse
|
120
|
Boivin JR, Nedivi E. Functional implications of inhibitory synapse placement on signal processing in pyramidal neuron dendrites. Curr Opin Neurobiol 2018; 51:16-22. [PMID: 29454834 DOI: 10.1016/j.conb.2018.01.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 01/23/2018] [Indexed: 01/02/2023]
Abstract
A rich literature describes inhibitory innervation of pyramidal neurons in terms of the distinct inhibitory cell types that target the soma, axon initial segment, or dendritic arbor. Less attention has been devoted to how localization of inhibition to specific parts of the pyramidal dendritic arbor influences dendritic signal detection and integration. The effect of inhibitory inputs can vary based on their placement on dendritic spines versus shaft, their distance from the soma, and the branch order of the dendrite they inhabit. Inhibitory synapses are also structurally dynamic, and the implications of these dynamics depend on their dendritic location. Here we consider the heterogeneous roles of inhibitory synapses as defined by their strategic placement on the pyramidal cell dendritic arbor.
Collapse
Affiliation(s)
- Josiah R Boivin
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Elly Nedivi
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| |
Collapse
|
121
|
Regulation of Synapse Development by Vgat Deletion from ErbB4-Positive Interneurons. J Neurosci 2018; 38:2533-2550. [PMID: 29431653 DOI: 10.1523/jneurosci.0669-17.2018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 01/22/2018] [Accepted: 01/29/2018] [Indexed: 11/21/2022] Open
Abstract
GABA signaling has been implicated in neural development; however, in vivo genetic evidence is missing because mutant mice lacking GABA activity die prematurely. Here, we studied synapse development by ablating vesicular GABA transporter (Vgat) in ErbB4+ interneurons. We show that inhibitory axo-somatic synapses onto pyramidal neurons vary from one cortical layer to another; however, inhibitory synapses on axon initial segments (AISs) were similar across layers. Conversely, parvalbumin-positive (PV+)/ErbB4+ interneurons and PV-only interneurons receive a higher number of inhibitory synapses from PV+ErbB4+ interneurons compared with ErbB4-only interneurons. Vgat deletion from ErbB4+ interneurons reduced axo-somatic or axo-axonic synapses from PV+ErbB4+ interneurons onto excitatory neurons. This effect was associated with corresponding changes in neurotransmission. However, the Vgat mutation seemed to have little effect on inhibitory synapses onto PV+ and/or ErbB4+ interneurons. Interestingly, perineuronal nets, extracellular matrix structures implicated in maturation, survival, protection, and plasticity of PV+ interneurons, were increased in the cortex of ErbB4-Vgat-/- mice. No apparent difference was observed between males and females. These results demonstrate that Vgat of ErbB4+ interneurons is essential for the development of inhibitory synapses onto excitatory neurons and suggest a role of GABA in circuit assembly.SIGNIFICANCE STATEMENT GABA has been implicated in neural development, but in vivo genetic evidence is missing because mutant mice lacking GABA die prematurely. Here, we ablated Vgat in ErbB4+ interneurons in an inducible manner. We provide evidence that the formation of inhibitory and excitatory synapses onto excitatory neurons requires Vgat in interneurons. In particular, inhibitory axo-somatic and axo-axonic synapses are more vulnerable. Our results suggest a role of GABA in circuit assembly.
Collapse
|
122
|
Osanai H, Minusa S, Tateno T. Micro-coil-induced Inhomogeneous Electric Field Produces sound-driven-like Neural Responses in Microcircuits of the Mouse Auditory Cortex In Vivo. Neuroscience 2018; 371:346-370. [DOI: 10.1016/j.neuroscience.2017.12.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 11/29/2017] [Accepted: 12/06/2017] [Indexed: 12/27/2022]
|
123
|
Takesian AE, Bogart LJ, Lichtman JW, Hensch TK. Inhibitory circuit gating of auditory critical-period plasticity. Nat Neurosci 2018; 21:218-227. [PMID: 29358666 PMCID: PMC5978727 DOI: 10.1038/s41593-017-0064-2] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 12/04/2017] [Indexed: 12/15/2022]
Abstract
Cortical sensory maps are remodeled during early life to adapt to the surrounding environment. Both sensory and contextual signals are important for induction of this plasticity, but how these signals converge to sculpt developing thalamocortical circuits remains largely unknown. Here we show that layer 1 (L1) of primary auditory cortex (A1) is a key hub where neuromodulatory and topographically organized thalamic inputs meet to tune the cortical layers below. Inhibitory interneurons in L1 send narrowly descending projections to differentially modulate thalamic drive to pyramidal and parvalbumin-expressing (PV) cells in L4, creating brief windows of intracolumnar activation. Silencing of L1 (but not VIP-expressing) cells abolishes map plasticity during the tonotopic critical period. Developmental transitions in nicotinic acetylcholine receptor (nAChR) sensitivity in these cells caused by Lynx1 protein can be overridden to extend critical-period closure. Notably, thalamocortical maps in L1 are themselves stable, and serve as a scaffold for cortical plasticity throughout life.
Collapse
Affiliation(s)
- Anne E Takesian
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Center for Brain Science, Department of Molecular & Cellular Biology, Harvard University, Cambridge, MA, USA
| | - Luke J Bogart
- Center for Brain Science, Department of Molecular & Cellular Biology, Harvard University, Cambridge, MA, USA
| | - Jeff W Lichtman
- Center for Brain Science, Department of Molecular & Cellular Biology, Harvard University, Cambridge, MA, USA
| | - Takao K Hensch
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA.
- Center for Brain Science, Department of Molecular & Cellular Biology, Harvard University, Cambridge, MA, USA.
| |
Collapse
|
124
|
Bohannon AS, Hablitz JJ. Developmental Changes in HCN Channel Modulation of Neocortical Layer 1 Interneurons. Front Cell Neurosci 2018; 12:20. [PMID: 29440994 PMCID: PMC5797556 DOI: 10.3389/fncel.2018.00020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 01/15/2018] [Indexed: 01/31/2023] Open
Abstract
Layer 1 (L1) interneurons (INs) play a key role in modulating the integration of inputs to pyramidal neurons (PNs) and controlling cortical network activity. Hyperpolarization-activated, cyclic nucleotide-gated, non-specific cation (HCN) channels are known to alter the intrinsic and synaptic excitability of principal components (PCs) as well as select populations of GABAergic INs. However, the developmental profile and functional role of HCN channels in diverse L1 IN populations is not completely understood. In the present study, we used electrophysiological characterization, in conjunction with unbiased hierarchical cluster analysis, to examine developmental modulation of L1 INs by HCN channels in the rat medial agranular cortex (AGm). We identified three physiologically discrete IN populations which were classified as regular spiking (RS), burst accommodating (BA) and non-accommodating (NA). A distinct developmental pattern of excitability modulation by HCN channels was observed for each group. RS and NA cells displayed distinct morphologies with modulation of EPSPs increasing in RS cells and decreasing in NA cells across development. The results indicate a possible role of HCN channels in the formation and maintenance of cortical circuits through alteration of the excitability of distinct AGm L1 INs.
Collapse
Affiliation(s)
- Andrew S Bohannon
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - John J Hablitz
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, United States
| |
Collapse
|
125
|
Anastasiades PG, Marques‐Smith A, Butt SJB. Studies of cortical connectivity using optical circuit mapping methods. J Physiol 2018; 596:145-162. [PMID: 29110301 PMCID: PMC5767689 DOI: 10.1113/jp273463] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 10/11/2017] [Indexed: 11/08/2022] Open
Abstract
An important consideration when probing the function of any neuron is to uncover the source of synaptic input onto the cell, its intrinsic physiology and efferent targets. Over the years, electrophysiological approaches have generated considerable insight into these properties in a variety of cortical neuronal subtypes and circuits. However, as researchers explore neuronal function in greater detail, they are increasingly turning to optical techniques to bridge the gap between local network interactions and behaviour. The application of optical methods has increased dramatically over the past decade, spurred on by the optogenetic revolution. In this review, we provide an account of recent innovations, providing researchers with a primer detailing circuit mapping strategies in the cerebral cortex. We will focus on technical aspects of performing neurotransmitter uncaging and channelrhodopsin-assisted circuit mapping, with the aim of identifying common pitfalls that can negatively influence the collection of reliable data.
Collapse
|
126
|
Uhlirova H, Kılıç K, Tian P, Sakadžić S, Gagnon L, Thunemann M, Desjardins M, Saisan PA, Nizar K, Yaseen MA, Hagler DJ, Vandenberghe M, Djurovic S, Andreassen OA, Silva GA, Masliah E, Kleinfeld D, Vinogradov S, Buxton RB, Einevoll GT, Boas DA, Dale AM, Devor A. The roadmap for estimation of cell-type-specific neuronal activity from non-invasive measurements. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0356. [PMID: 27574309 DOI: 10.1098/rstb.2015.0356] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/14/2016] [Indexed: 12/22/2022] Open
Abstract
The computational properties of the human brain arise from an intricate interplay between billions of neurons connected in complex networks. However, our ability to study these networks in healthy human brain is limited by the necessity to use non-invasive technologies. This is in contrast to animal models where a rich, detailed view of cellular-level brain function with cell-type-specific molecular identity has become available due to recent advances in microscopic optical imaging and genetics. Thus, a central challenge facing neuroscience today is leveraging these mechanistic insights from animal studies to accurately draw physiological inferences from non-invasive signals in humans. On the essential path towards this goal is the development of a detailed 'bottom-up' forward model bridging neuronal activity at the level of cell-type-specific populations to non-invasive imaging signals. The general idea is that specific neuronal cell types have identifiable signatures in the way they drive changes in cerebral blood flow, cerebral metabolic rate of O2 (measurable with quantitative functional Magnetic Resonance Imaging), and electrical currents/potentials (measurable with magneto/electroencephalography). This forward model would then provide the 'ground truth' for the development of new tools for tackling the inverse problem-estimation of neuronal activity from multimodal non-invasive imaging data.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'.
Collapse
Affiliation(s)
- Hana Uhlirova
- Department of Radiology, UCSD, La Jolla, CA 92093, USA CEITEC-Central European Institute of Technology and Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Brno, Czech Republic
| | - Kıvılcım Kılıç
- Department of Neurosciences, UCSD, La Jolla, CA 92093, USA
| | - Peifang Tian
- Department of Neurosciences, UCSD, La Jolla, CA 92093, USA Department of Physics, John Carroll University, University Heights, OH 44118, USA
| | - Sava Sakadžić
- Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA 02129, USA
| | - Louis Gagnon
- Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA 02129, USA
| | | | | | - Payam A Saisan
- Department of Neurosciences, UCSD, La Jolla, CA 92093, USA
| | - Krystal Nizar
- Neurosciences Graduate Program, UCSD, La Jolla, CA 92093, USA
| | - Mohammad A Yaseen
- Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA 02129, USA
| | | | - Matthieu Vandenberghe
- Department of Radiology, UCSD, La Jolla, CA 92093, USA NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital and University of Oslo, 0407 Oslo, Norway
| | - Srdjan Djurovic
- Department of Medical Genetics, Oslo University Hospital, 0407 Oslo, Norway NORMENT, KG Jebsen Centre for Psychosis Research, Department of Clinical Science, University of Bergen, 5020 Bergen, Norway
| | - Ole A Andreassen
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital and University of Oslo, 0407 Oslo, Norway
| | - Gabriel A Silva
- Department of Bioengineering, UCSD, La Jolla, CA 92093, USA Department of Opthalmology, UCSD, La Jolla, CA 92093, USA
| | | | - David Kleinfeld
- Department of Physics, UCSD, La Jolla, CA 92093, USA Department of Electrical and Computer Engineering, UCSD, La Jolla, CA 92093, USA Section of Neurobiology, UCSD, La Jolla, CA 92093, USA
| | - Sergei Vinogradov
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | | - Gaute T Einevoll
- Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, 1432 Ås, Norway Department of Physics, University of Oslo, 0316 Oslo, Norway
| | - David A Boas
- Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA 02129, USA
| | - Anders M Dale
- Department of Radiology, UCSD, La Jolla, CA 92093, USA Department of Neurosciences, UCSD, La Jolla, CA 92093, USA
| | - Anna Devor
- Department of Radiology, UCSD, La Jolla, CA 92093, USA Department of Neurosciences, UCSD, La Jolla, CA 92093, USA Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA 02129, USA
| |
Collapse
|
127
|
Systematic population spike delays across cortical layers within and between primary sensory areas. Sci Rep 2017; 7:15267. [PMID: 29127394 PMCID: PMC5681572 DOI: 10.1038/s41598-017-15611-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 10/30/2017] [Indexed: 12/12/2022] Open
Abstract
The coordinated propagation of activity across cortical layers enables simultaneous local computation and inter-areal interactions. A pattern of upward propagation from deeper to more superficial layers, which has been repeatedly demonstrated in spontaneous activity, would allow these functions to occur in parallel. But it remains unclear whether upward propagation also occurs for stimulus evoked activity, and how it relates to activity in other cortical areas. Here we used a new method to analyze relative delays between spikes obtained from simultaneous laminar recordings in primary sensory cortex (S1) of both hemispheres. The results identified systematic spike delays across cortical layers that showed a general upward propagation of activity in evoked and spontaneous activity. Systematic spike delays were also observed between hemispheres. After spikes in one S1 the delays in the other S1 were shortest at infragranular layers and increased in the upward direction. Model comparisons furthermore showed that upward propagation was better explained as a step-wise progression over cortical layers than as a traveling wave. The results are in line with the notion that upward propagation functionally integrates activity into local processing at superficial layers, while efficiently allowing for simultaneous inter-areal interactions.
Collapse
|
128
|
Parvalbumin-expressing interneurons can act solo while somatostatin-expressing interneurons act in chorus in most cases on cortical pyramidal cells. Sci Rep 2017; 7:12764. [PMID: 28986578 PMCID: PMC5630625 DOI: 10.1038/s41598-017-12958-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 09/13/2017] [Indexed: 11/24/2022] Open
Abstract
Neural circuits in the cerebral cortex consist primarily of excitatory pyramidal (Pyr) cells and inhibitory interneurons. Interneurons are divided into several subtypes, in which the two major groups are those expressing parvalbumin (PV) or somatostatin (SOM). These subtypes of interneurons are reported to play distinct roles in tuning and/or gain of visual response of pyramidal cells in the visual cortex. It remains unclear whether there is any quantitative and functional difference between the PV → Pyr and SOM → Pyr connections. We compared unitary inhibitory postsynaptic currents (uIPSCs) evoked by electrophysiological activation of single presynaptic interneurons with population IPSCs evoked by photo-activation of a mass of interneurons in vivo and in vitro in transgenic mice in which PV or SOM neurons expressed channelrhodopsin-2, and found that at least about 14 PV neurons made strong connections with a postsynaptic Pyr cell while a much larger number of SOM neurons made weak connections. Activation or suppression of single PV neurons modified visual responses of postsynaptic Pyr cells in 6 of 7 pairs whereas that of single SOM neurons showed no significant modification in 8 of 11 pairs, suggesting that PV neurons can act solo whereas most of SOM neurons may act in chorus on Pyr cells.
Collapse
|
129
|
Uncertainty and stress: Why it causes diseases and how it is mastered by the brain. Prog Neurobiol 2017; 156:164-188. [DOI: 10.1016/j.pneurobio.2017.05.004] [Citation(s) in RCA: 295] [Impact Index Per Article: 42.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 05/22/2017] [Accepted: 05/24/2017] [Indexed: 02/06/2023]
|
130
|
Abstract
Cortical networks are composed of glutamatergic excitatory projection neurons and local GABAergic inhibitory interneurons that gate signal flow and sculpt network dynamics. Although they represent a minority of the total neocortical neuronal population, GABAergic interneurons are highly heterogeneous, forming functional classes based on their morphological, electrophysiological, and molecular features, as well as connectivity and in vivo patterns of activity. Here we review our current understanding of neocortical interneuron diversity and the properties that distinguish cell types. We then discuss how the involvement of multiple cell types, each with a specific set of cellular properties, plays a crucial role in diversifying and increasing the computational power of a relatively small number of simple circuit motifs forming cortical networks. We illustrate how recent advances in the field have shed light onto the mechanisms by which GABAergic inhibition contributes to network operations.
Collapse
|
131
|
D'Souza RD, Burkhalter A. A Laminar Organization for Selective Cortico-Cortical Communication. Front Neuroanat 2017; 11:71. [PMID: 28878631 PMCID: PMC5572236 DOI: 10.3389/fnana.2017.00071] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 08/07/2017] [Indexed: 11/13/2022] Open
Abstract
The neocortex is central to mammalian cognitive ability, playing critical roles in sensory perception, motor skills and executive function. This thin, layered structure comprises distinct, functionally specialized areas that communicate with each other through the axons of pyramidal neurons. For the hundreds of such cortico-cortical pathways to underlie diverse functions, their cellular and synaptic architectures must differ so that they result in distinct computations at the target projection neurons. In what ways do these pathways differ? By originating and terminating in different laminae, and by selectively targeting specific populations of excitatory and inhibitory neurons, these “interareal” pathways can differentially control the timing and strength of synaptic inputs onto individual neurons, resulting in layer-specific computations. Due to the rapid development in transgenic techniques, the mouse has emerged as a powerful mammalian model for understanding the rules by which cortical circuits organize and function. Here we review our understanding of how cortical lamination constrains long-range communication in the mammalian brain, with an emphasis on the mouse visual cortical network. We discuss the laminar architecture underlying interareal communication, the role of neocortical layers in organizing the balance of excitatory and inhibitory actions, and highlight the structure and function of layer 1 in mouse visual cortex.
Collapse
Affiliation(s)
- Rinaldo D D'Souza
- Department of Neuroscience, Washington University School of MedicineSt. Louis, MO, United States
| | - Andreas Burkhalter
- Department of Neuroscience, Washington University School of MedicineSt. Louis, MO, United States
| |
Collapse
|
132
|
Inhibitory Gating of Basolateral Amygdala Inputs to the Prefrontal Cortex. J Neurosci 2017; 36:9391-406. [PMID: 27605614 DOI: 10.1523/jneurosci.0874-16.2016] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 07/18/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Interactions between the prefrontal cortex (PFC) and basolateral amygdala (BLA) regulate emotional behaviors. However, a circuit-level understanding of functional connections between these brain regions remains incomplete. The BLA sends prominent glutamatergic projections to the PFC, but the overall influence of these inputs is predominantly inhibitory. Here we combine targeted recordings and optogenetics to examine the synaptic underpinnings of this inhibition in the mouse infralimbic PFC. We find that BLA inputs preferentially target layer 2 corticoamygdala over neighboring corticostriatal neurons. However, these inputs make even stronger connections onto neighboring parvalbumin and somatostatin expressing interneurons. Inhibitory connections from these two populations of interneurons are also much stronger onto corticoamygdala neurons. Consequently, BLA inputs are able to drive robust feedforward inhibition via two parallel interneuron pathways. Moreover, the contributions of these interneurons shift during repetitive activity, due to differences in short-term synaptic dynamics. Thus, parvalbumin interneurons are activated at the start of stimulus trains, whereas somatostatin interneuron activation builds during these trains. Together, these results reveal how the BLA impacts the PFC through a complex interplay of direct excitation and feedforward inhibition. They also highlight the roles of targeted connections onto multiple projection neurons and interneurons in this cortical circuit. Our findings provide a mechanistic understanding for how the BLA can influence the PFC circuit, with important implications for how this circuit participates in the regulation of emotion. SIGNIFICANCE STATEMENT The prefrontal cortex (PFC) and basolateral amygdala (BLA) interact to control emotional behaviors. Here we show that BLA inputs elicit direct excitation and feedforward inhibition of layer 2 projection neurons in infralimbic PFC. BLA inputs are much stronger at corticoamygdala neurons compared with nearby corticostriatal neurons. However, these inputs are even more powerful at parvalbumin and somatostatin expressing interneurons. BLA inputs thus activate two parallel inhibitory networks, whose contributions change during repetitive activity. Finally, connections from these interneurons are also more powerful at corticoamygdala neurons compared with corticostriatal neurons. Together, our results demonstrate how the BLA predominantly inhibits the PFC via a complex sequence involving multiple cell-type and input-specific connections.
Collapse
|
133
|
Yamagata T, Ogiwara I, Mazaki E, Yanagawa Y, Yamakawa K. Nav1.2 is expressed in caudal ganglionic eminence-derived disinhibitory interneurons: Mutually exclusive distributions of Nav1.1 and Nav1.2. Biochem Biophys Res Commun 2017; 491:1070-1076. [PMID: 28784306 DOI: 10.1016/j.bbrc.2017.08.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 08/02/2017] [Indexed: 11/15/2022]
Abstract
Nav1.1 and Nav1.2 are the voltage-gated sodium channel pore-forming alpha I and II subunits, encoded by the genes SCN1A and SCN2A. Although mutations of both genes have similarly been described in patients with epilepsy, autism and/or intellectual disability, their expression sites in brain are largely distinct. Nav1.1 was shown to be expressed dominantly in parvalbumin (PV)-positive or somatostatin (SST)-positive inhibitory neurons and in a sparsely-distributed subpopulation of excitatory neurons. In contrast, Nav1.2 has been reported to be dominantly expressed in excitatory neurons. Here we show that Nav1.2 is also expressed in caudal ganglionic eminence (CGE)-derived inhibitory neurons, and expressions of Nav1.1 and Nav1.2 are mutually-exclusive in many of brain regions including neocortex, hippocampus, cerebellum, striatum and globus pallidus. In neocortex at postnatal day 15, in addition to the expression in excitatory neurons we show that Nav1.2 is expressed in reelin (RLN)-positive/SST-negative inhibitory neurons that are presumably single-bouquet cells because of their cortical layer I-limited distribution, and vasoactive intestinal peptide (VIP)-positive neurons that would be multipolar cell because of their layer I/II margin and layer VI distribution. Although Nav1.2 has previously been reported to be expressed in SST-positive cells, we here show that Nav1.2 is not expressed in either of PV-positive or SST-positive inhibitory neurons. PV-positive and SST-positive inhibitory neurons derive from medial ganglionic eminence (MGE) and innervate excitatory neurons, while VIP-positive and RLN-positive/SST-negative inhibitory neurons derive from CGE, innervate on inhibitory neurons and play disinhibitory roles in the neural network. Our results therefore indicate that, while Nav1.1 is expressed in MEG-derived inhibitory neurons, Nav1.2 is expressed in CGE-derived disinhibitory interneurons in addition to excitatory neurons. These findings should contribute to understanding of the pathology of neurodevelopmental diseases caused by SCN2A mutations.
Collapse
Affiliation(s)
- Tetsushi Yamagata
- Laboratory for Neurogenetics, RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan
| | - Ikuo Ogiwara
- Laboratory for Neurogenetics, RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan; Department of Physiology, Nippon Medical School, Tokyo 113-8602, Japan
| | - Emi Mazaki
- Laboratory for Neurogenetics, RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan
| | - Yuchio Yanagawa
- Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine, Maebashi 371-8511, Japan
| | - Kazuhiro Yamakawa
- Laboratory for Neurogenetics, RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan.
| |
Collapse
|
134
|
Fogerson PM, Huguenard JR. Tapping the Brakes: Cellular and Synaptic Mechanisms that Regulate Thalamic Oscillations. Neuron 2017; 92:687-704. [PMID: 27883901 DOI: 10.1016/j.neuron.2016.10.024] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 10/03/2016] [Accepted: 10/10/2016] [Indexed: 12/26/2022]
Abstract
Thalamic oscillators contribute to both normal rhythms associated with sleep and anesthesia and abnormal, hypersynchronous oscillations that manifest behaviorally as absence seizures. In this review, we highlight new findings that refine thalamic contributions to cortical rhythms and suggest that thalamic oscillators may be subject to both local and global control. We describe endogenous thalamic mechanisms that limit network synchrony and discuss how these protective brakes might be restored to prevent absence seizures. Finally, we describe how intrinsic and circuit-level specializations among thalamocortical loops may determine their involvement in widespread oscillations and render subsets of thalamic nuclei especially vulnerable to pathological synchrony.
Collapse
Affiliation(s)
- P Michelle Fogerson
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - John R Huguenard
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA.
| |
Collapse
|
135
|
Peikon ID, Kebschull JM, Vagin VV, Ravens DI, Sun YC, Brouzes E, Corrêa IR, Bressan D, Zador AM. Using high-throughput barcode sequencing to efficiently map connectomes. Nucleic Acids Res 2017; 45:e115. [PMID: 28449067 PMCID: PMC5499584 DOI: 10.1093/nar/gkx292] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 03/20/2017] [Accepted: 04/13/2017] [Indexed: 01/16/2023] Open
Abstract
The function of a neural circuit is determined by the details of its synaptic connections. At present, the only available method for determining a neural wiring diagram with single synapse precision-a 'connectome'-is based on imaging methods that are slow, labor-intensive and expensive. Here, we present SYNseq, a method for converting the connectome into a form that can exploit the speed and low cost of modern high-throughput DNA sequencing. In SYNseq, each neuron is labeled with a unique random nucleotide sequence-an RNA 'barcode'-which is targeted to the synapse using engineered proteins. Barcodes in pre- and postsynaptic neurons are then associated through protein-protein crosslinking across the synapse, extracted from the tissue, and joined into a form suitable for sequencing. Although our failure to develop an efficient barcode joining scheme precludes the widespread application of this approach, we expect that with further development SYNseq will enable tracing of complex circuits at high speed and low cost.
Collapse
Affiliation(s)
- Ian D. Peikon
- Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Justus M. Kebschull
- Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Vasily V. Vagin
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Diana I. Ravens
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Yu-Chi Sun
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Eric Brouzes
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
- Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | | | - Dario Bressan
- Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
- Cancer Research UK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge CB2 0RE, UK
| | - Anthony M. Zador
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| |
Collapse
|
136
|
Shadlen MN, Shohamy D. Decision Making and Sequential Sampling from Memory. Neuron 2017; 90:927-39. [PMID: 27253447 DOI: 10.1016/j.neuron.2016.04.036] [Citation(s) in RCA: 173] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 04/18/2016] [Accepted: 04/22/2016] [Indexed: 12/16/2022]
Abstract
Decisions take time, and as a rule more difficult decisions take more time. But this only raises the question of what consumes the time. For decisions informed by a sequence of samples of evidence, the answer is straightforward: more samples are available with more time. Indeed, the speed and accuracy of such decisions are explained by the accumulation of evidence to a threshold or bound. However, the same framework seems to apply to decisions that are not obviously informed by sequences of evidence samples. Here, we proffer the hypothesis that the sequential character of such tasks involves retrieval of evidence from memory. We explore this hypothesis by focusing on value-based decisions and argue that mnemonic processes can account for regularities in choice and decision time. We speculate on the neural mechanisms that link sampling of evidence from memory to circuits that represent the accumulated evidence bearing on a choice. We propose that memory processes may contribute to a wider class of decisions that conform to the regularities of choice-reaction time predicted by the sequential sampling framework.
Collapse
Affiliation(s)
- Michael N Shadlen
- Howard Hughes Medical Institute and Department of Neuroscience, Columbia University, New York, NY 10032, USA; Zuckerman Mind Brain Behavior Institute and Kavli Institute for Brain Science, Columbia University, New York, NY 10032, USA.
| | - Daphna Shohamy
- Department of Psychology, Columbia University, New York, NY 10032, USA; Zuckerman Mind Brain Behavior Institute and Kavli Institute for Brain Science, Columbia University, New York, NY 10032, USA.
| |
Collapse
|
137
|
Feldmeyer D, Qi G, Emmenegger V, Staiger JF. Inhibitory interneurons and their circuit motifs in the many layers of the barrel cortex. Neuroscience 2017; 368:132-151. [PMID: 28528964 DOI: 10.1016/j.neuroscience.2017.05.027] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 05/11/2017] [Accepted: 05/12/2017] [Indexed: 10/19/2022]
Abstract
Recent years have seen substantial progress in studying the structural and functional properties of GABAergic interneurons and their roles in the neuronal networks of barrel cortex. Although GABAergic interneurons represent only about 12% of the total number of neocortical neurons, they are extremely diverse with respect to their structural and functional properties. It has become clear that barrel cortex interneurons not only serve the maintenance of an appropriate excitation/inhibition balance but also are directly involved in sensory processing. In this review we present different interneuron types and their axonal projection pattern framework in the context of the laminar and columnar organization of the barrel cortex. The main focus is here on the most prominent interneuron types, i.e. basket cells, chandelier cells, Martinotti cells, bipolar/bitufted cells and neurogliaform cells, but interneurons with more unusual axonal domains will also be mentioned. We describe their developmental origin, their classification with respect to molecular, morphological and intrinsic membrane and synaptic properties. Most importantly, we will highlight the most prominent circuit motifs these interneurons are involved in and in which way they serve feed-forward inhibition, feedback inhibition and disinhibition. Finally, this will be put into context to their functional roles in sensory signal perception and processing in the whisker system and beyond.
Collapse
Affiliation(s)
- Dirk Feldmeyer
- Institute of Neuroscience and Medicine, INM-2, Research Center Jülich, D-52425 Jülich, Germany; Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, D-52074 Aachen, Germany; Jülich Aachen Research Alliance, Translational Brain Medicine (JARA Brain), D-52074 Aachen, Germany.
| | - Guanxiao Qi
- Institute of Neuroscience and Medicine, INM-2, Research Center Jülich, D-52425 Jülich, Germany
| | - Vishalini Emmenegger
- Institute of Neuroscience and Medicine, INM-2, Research Center Jülich, D-52425 Jülich, Germany; Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, D-52074 Aachen, Germany
| | - Jochen F Staiger
- Institute for Neuroanatomy, University Medical Center Göttingen, Georg-August-University, Göttingen D-37075, Germany.
| |
Collapse
|
138
|
Tao C, Zhang G, Zhou C, Wang L, Yan S, Tao HW, Zhang LI, Zhou Y, Xiong Y. Diversity in Excitation-Inhibition Mismatch Underlies Local Functional Heterogeneity in the Rat Auditory Cortex. Cell Rep 2017; 19:521-531. [PMID: 28423316 DOI: 10.1016/j.celrep.2017.03.061] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 02/09/2017] [Accepted: 03/21/2017] [Indexed: 11/29/2022] Open
Abstract
Cortical neurons are heterogeneous in their functional properties. This heterogeneity is fundamental for the processing of different features of sensory information. However, functional diversity within a local group of neurons is poorly understood. Here, we demonstrate that neighboring cortical neurons in layer 5 but not those of layer 4 of the rat anterior auditory field (AAF) exhibited a surprisingly high level of diversity in tonal receptive fields. In vivo whole-cell voltage-clamp recordings revealed that the diversity of frequency representation was due to a spectral mismatch between synaptic excitation and inhibition to varying degrees. The spectral distribution of excitation was skewed at different levels, whereas inhibition was homogeneous and non-skewed, similar to the summed spiking activity of local neuronal ensembles, which further enhanced diversity. Our results indicate that AAF in the auditory cortex is involved in processing auditory information in a highly refined manner that is important for complex pattern recognition.
Collapse
Affiliation(s)
- Can Tao
- Department of Neurobiology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, Chongqing 400038, China
| | - Guangwei Zhang
- Department of Neurobiology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, Chongqing 400038, China
| | - Chang Zhou
- Department of Neurobiology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, Chongqing 400038, China
| | - Lijuan Wang
- Department of Neurobiology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, Chongqing 400038, China
| | - Sumei Yan
- Department of Neurobiology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, Chongqing 400038, China
| | - Huizhong Whit Tao
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Li I Zhang
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Yi Zhou
- Department of Neurobiology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, Chongqing 400038, China.
| | - Ying Xiong
- Department of Neurobiology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, Chongqing 400038, China.
| |
Collapse
|
139
|
Combination of High-density Microelectrode Array and Patch Clamp Recordings to Enable Studies of Multisynaptic Integration. Sci Rep 2017; 7:978. [PMID: 28428560 PMCID: PMC5430511 DOI: 10.1038/s41598-017-00981-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 03/17/2017] [Indexed: 12/15/2022] Open
Abstract
We present a novel, all-electric approach to record and to precisely control the activity of tens of individual presynaptic neurons. The method allows for parallel mapping of the efficacy of multiple synapses and of the resulting dynamics of postsynaptic neurons in a cortical culture. For the measurements, we combine an extracellular high-density microelectrode array, featuring 11’000 electrodes for extracellular recording and stimulation, with intracellular patch-clamp recording. We are able to identify the contributions of individual presynaptic neurons - including inhibitory and excitatory synaptic inputs - to postsynaptic potentials, which enables us to study dendritic integration. Since the electrical stimuli can be controlled at microsecond resolution, our method enables to evoke action potentials at tens of presynaptic cells in precisely orchestrated sequences of high reliability and minimum jitter. We demonstrate the potential of this method by evoking short- and long-term synaptic plasticity through manipulation of multiple synaptic inputs to a specific neuron.
Collapse
|
140
|
Muñoz W, Tremblay R, Levenstein D, Rudy B. Layer-specific modulation of neocortical dendritic inhibition during active wakefulness. Science 2017; 355:954-959. [PMID: 28254942 DOI: 10.1126/science.aag2599] [Citation(s) in RCA: 205] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 02/06/2017] [Indexed: 10/25/2024]
Abstract
γ-Aminobutyric acid (GABA)ergic inputs are strategically positioned to gate synaptic integration along the dendritic arbor of pyramidal cells. However, their spatiotemporal dynamics during behavior are poorly understood. Using an optical-tagging electrophysiological approach to record and label somatostatin-expressing (Sst) interneurons (GABAergic neurons specialized for dendritic inhibition), we discovered a layer-specific modulation of their activity in behaving mice. Sst interneuron subtypes, residing in different cortical layers and innervating complementary laminar domains, exhibited opposite activity changes during transitions to active wakefulness. The relative weight of vasoactive intestinal peptide-expressing (Vip) interneuron-mediated inhibition of distinct Sst interneurons and cholinergic modulation determined their in vivo activity. These results reveal a state-dependent laminar influence of Sst interneuron-mediated inhibition, with implications for the compartmentalized regulation of dendritic signaling in the mammalian neocortex.
Collapse
Affiliation(s)
- William Muñoz
- Neuroscience Institute and Department of Neuroscience and Physiology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Robin Tremblay
- Neuroscience Institute and Department of Neuroscience and Physiology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Daniel Levenstein
- Neuroscience Institute and Department of Neuroscience and Physiology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
- Center for Neural Science, New York University, 4 Washington Place, New York, NY 10003, USA
| | - Bernardo Rudy
- Neuroscience Institute and Department of Neuroscience and Physiology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA.
- Department of Anesthesiology, Perioperative Care and Pain Medicine, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| |
Collapse
|
141
|
Hierlemann A. Direct Interfacing of Neurons to Highly Integrated Microsystems. PROCEEDINGS. IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS 2017; 2017:199-204. [PMID: 28677939 PMCID: PMC5448667 DOI: 10.1109/memsys.2017.7863375] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The use of large high-density transducer arrays enables fundamentally new neuroscientific insights through enabling high-throughput monitoring of action potentials of larger neuronal networks (> 1000 neurons) over extended time to see effects of disturbances or developmental effects, and through facilitating detailed investigations of neuronal signaling characteristics at subcellular level, for example, the study of axonal signal propagation that has been largely inaccessible to established methods. Applications include research in neural diseases and pharmacology.
Collapse
Affiliation(s)
- Andreas Hierlemann
- ETH Zurich, Department of Biosystems Science and Engineering, CH-4058, Basel, Switzerland
| |
Collapse
|
142
|
Sohn J, Okamoto S, Kataoka N, Kaneko T, Nakamura K, Hioki H. Differential Inputs to the Perisomatic and Distal-Dendritic Compartments of VIP-Positive Neurons in Layer 2/3 of the Mouse Barrel Cortex. Front Neuroanat 2016; 10:124. [PMID: 28066195 PMCID: PMC5167764 DOI: 10.3389/fnana.2016.00124] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Accepted: 12/07/2016] [Indexed: 11/13/2022] Open
Abstract
The recurrent network composed of excitatory and inhibitory neurons is fundamental to neocortical function. Inhibitory neurons in the mammalian neocortex are molecularly diverse, and individual cell types play unique functional roles in the neocortical microcircuit. Recently, vasoactive intestinal polypeptide-positive (VIP+) neurons, comprising a subclass of inhibitory neurons, have attracted particular attention because they can disinhibit pyramidal cells through inhibition of other types of inhibitory neurons, such as parvalbumin- (PV+) and somatostatin-positive (SOM+) inhibitory neurons, promoting sensory information processing. Although VIP+ neurons have been reported to receive synaptic inputs from PV+ and SOM+ inhibitory neurons as well as from cortical and thalamic excitatory neurons, the somatodendritic localization of these synaptic inputs has yet to be elucidated at subcellular spatial resolution. In the present study, we visualized the somatodendritic membranes of layer (L) 2/3 VIP+ neurons by injecting a newly developed adeno-associated virus (AAV) vector into the barrel cortex of VIP-Cre knock-in mice, and we determined the extensive ramification of VIP+ neuron dendrites in the vertical orientation. After immunohistochemical labeling of presynaptic boutons and postsynaptic structures, confocal laser scanning microscopy revealed that the synaptic contacts were unevenly distributed throughout the perisomatic (<100 μm from the somata) and distal-dendritic compartments (≥100 μm) of VIP+ neurons. Both corticocortical and thalamocortical excitatory neurons preferentially targeted the distal-dendritic compartment of VIP+ neurons. On the other hand, SOM+ and PV+ inhibitory neurons preferentially targeted the distal-dendritic and perisomatic compartments of VIP+ neurons, respectively. Notably, VIP+ neurons had few reciprocal connections. These observations suggest different inhibitory effects of SOM+ and PV+ neuronal inputs on VIP+ neuron activity; inhibitory inputs from SOM+ neurons likely modulate excitatory inputs locally in dendrites, while PV+ neurons could efficiently interfere with action potential generation through innervation of the perisomatic domain of VIP+ neurons. The present study, which shows a precise configuration of site-specific inputs, provides a structural basis for the integration mechanism of synaptic inputs to VIP+ neurons.
Collapse
Affiliation(s)
- Jaerin Sohn
- Department of Morphological Brain Science, Graduate School of Medicine, Kyoto UniversityKyoto, Japan; Division of Cerebral Circuitry, National Institute for Physiological SciencesOkazaki, Japan
| | - Shinichiro Okamoto
- Department of Morphological Brain Science, Graduate School of Medicine, Kyoto University Kyoto, Japan
| | - Naoya Kataoka
- Department of Integrative Physiology, Nagoya University Graduate School of Medicine Nagoya, Japan
| | - Takeshi Kaneko
- Department of Morphological Brain Science, Graduate School of Medicine, Kyoto University Kyoto, Japan
| | - Kazuhiro Nakamura
- Department of Integrative Physiology, Nagoya University Graduate School of MedicineNagoya, Japan; Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST)Kawaguchi, Japan
| | - Hiroyuki Hioki
- Department of Morphological Brain Science, Graduate School of Medicine, Kyoto University Kyoto, Japan
| |
Collapse
|
143
|
Abstract
Predictive coding theories of sensory brain function interpret the hierarchical construction of the cerebral cortex as a Bayesian, generative model capable of predicting the sensory data consistent with any given percept. Predictions are fed backward in the hierarchy and reciprocated by prediction error in the forward direction, acting to modify the representation of the outside world at increasing levels of abstraction, and so to optimize the nature of perception over a series of iterations. This accounts for many ‘illusory’ instances of perception where what is seen (heard, etc.) is unduly influenced by what is expected, based on past experience. This simple conception, the hierarchical exchange of prediction and prediction error, confronts a rich cortical microcircuitry that is yet to be fully documented. This article presents the view that, in the current state of theory and practice, it is profitable to begin a two-way exchange: that predictive coding theory can support an understanding of cortical microcircuit function, and prompt particular aspects of future investigation, whilst existing knowledge of microcircuitry can, in return, influence theoretical development. As an example, a neural inference arising from the earliest formulations of predictive coding is that the source populations of forward and backward pathways should be completely separate, given their functional distinction; this aspect of circuitry – that neurons with extrinsically bifurcating axons do not project in both directions – has only recently been confirmed. Here, the computational architecture prescribed by a generalized (free-energy) formulation of predictive coding is combined with the classic ‘canonical microcircuit’ and the laminar architecture of hierarchical extrinsic connectivity to produce a template schematic, that is further examined in the light of (a) updates in the microcircuitry of primate visual cortex, and (b) rapid technical advances made possible by transgenic neural engineering in the mouse. The exercise highlights a number of recurring themes, amongst them the consideration of interneuron diversity as a spur to theoretical development and the potential for specifying a pyramidal neuron’s function by its individual ‘connectome,’ combining its extrinsic projection (forward, backward or subcortical) with evaluation of its intrinsic network (e.g., unidirectional versus bidirectional connections with other pyramidal neurons).
Collapse
Affiliation(s)
- Stewart Shipp
- Laboratory of Visual Perceptual Mechanisms, Institute of Neuroscience, Chinese Academy of SciencesShanghai, China; INSERM U1208, Stem Cell and Brain Research InstituteBron, France; Department of Visual Neuroscience, UCL Institute of OphthalmologyLondon, UK
| |
Collapse
|
144
|
Chanauria N, Bharmauria V, Bachatene L, Cattan S, Rouat J, Molotchnikoff S. Comparative effects of adaptation on layers II-III and V-VI neurons in cat V1. Eur J Neurosci 2016; 44:3094-3104. [PMID: 27740707 DOI: 10.1111/ejn.13439] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 10/04/2016] [Accepted: 10/06/2016] [Indexed: 12/23/2022]
Abstract
V1 is fundamentally grouped into columns that descend from layers II-III to V-VI. Neurons inherent to visual cortex are capable of adapting to changes in the incoming stimuli that drive the cortical plasticity. A principle feature called orientation selectivity can be altered by the presentation of non-optimal stimulus called 'adapter'. When triggered, LGN cells impinge upon layer IV and further relay the information to deeper layers via layers II-III. Using different adaptation protocols, neuronal plasticity can be investigated. Superficial neurons in area V1 are well acknowledged to exhibit attraction and repulsion by shifting their tuning peaks when challenged by a non-optimal stimulus called 'adapter'. Layers V-VI neurons in spite of partnering layers II-III neurons in cortical computation have not been explored simultaneously toward adaptation. We believe that adaptation not only affects cells specific to a layer but modifies the entire column. In this study, through simultaneous multiunit recordings in anesthetized cats using a multichannel depth electrode, we show for the first time how layers V-VI neurons (1000-1200 μm) along with layers II-III neurons (300-500 μm) exhibit plasticity in response to adaptation. Our results demonstrate that superficial and deeper layer neurons react synonymously toward adapter by exhibiting similar behavioral properties. The neurons displayed similar amplitude of shift and maintained equivalent sharpness of Gaussian tuning peaks before and the following adaptation. It appears that a similar mechanism, belonging to all layers, is responsible for the analog outcome of the neurons' experience with adapter.
Collapse
Affiliation(s)
- Nayan Chanauria
- Neurophysiology of Visual System, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada
| | - Vishal Bharmauria
- Neurophysiology of Visual System, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada.,The Visuomotor Neuroscience Lab, Centre for Vision Research, Faculty of Health, York University, Toronto, ON, Canada
| | - Lyes Bachatene
- Neurophysiology of Visual System, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada.,Department of Nuclear Medicine and Radiobiology, Faculty of Medicine and Health Sciences (CHUS), SNAIL
- Sherbrooke Neuro Analysis and Imaging Lab, University of Sherbrooke, Sherbrooke, QC, Canada
| | - Sarah Cattan
- Neurophysiology of Visual System, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada
| | - Jean Rouat
- Neurophysiology of Visual System, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada.,Département de Génie Électrique et Génie Informatique, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Stéphane Molotchnikoff
- Neurophysiology of Visual System, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succursale Centre-Ville, Montréal, QC, H3C 3J7, Canada
| |
Collapse
|
145
|
Aracri P, Meneghini S, Coatti A, Amadeo A, Becchetti A. α4β2 ∗ nicotinic receptors stimulate GABA release onto fast-spiking cells in layer V of mouse prefrontal (Fr2) cortex. Neuroscience 2016; 340:48-61. [PMID: 27793780 PMCID: PMC5231322 DOI: 10.1016/j.neuroscience.2016.10.045] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 10/08/2016] [Accepted: 10/18/2016] [Indexed: 11/24/2022]
Abstract
α4β2∗ nAChRs stimulate IPSCs in FS interneurons, in layer V of the mouse PFC (Fr2). In P16–P63 mice, nicotine increased both IPSC and mIPSC frequencies. GABAergic terminals adjacent to PV+ cells expressed α4 nAChR. The percentage of FS cells with somatic α4β2∗ currents decreased with age. Hence, nAChRs may be able to induce local circuit disinhibition in Fr2 PFC.
Nicotinic acetylcholine receptors (nAChRs) produce widespread and complex effects on neocortex excitability. We studied how heteromeric nAChRs regulate inhibitory post-synaptic currents (IPSCs), in fast-spiking (FS) layer V neurons of the mouse frontal area 2 (Fr2). In the presence of blockers of ionotropic glutamate receptors, tonic application of 10 μM nicotine augmented the spontaneous IPSC frequency, with minor alterations of amplitudes and kinetics. These effects were studied since the 3rd postnatal week, and persisted throughout the first two months of postnatal life. The action of nicotine was blocked by 1 μM dihydro-β-erythroidine (DHβE; specific for α4∗ nAChRs), but not 10 nM methyllycaconitine (MLA; specific for α7∗ nAChRs). It was mimicked by 10 nM 5-iodo-3-[2(S)-azetidinylmethoxy]pyridine (5-IA; which activates β2∗ nAChRs). Similar results were obtained on miniature IPSCs (mIPSCs). Moreover, during the first five postnatal weeks, approximately 50% of FS cells displayed DHβE-sensitive whole-cell nicotinic currents. This percentage decreased to ∼5% in mice older than P45. By confocal microscopy, the α4 nAChR subunit was immunocytochemically identified on interneurons expressing either parvalbumin (PV), which mainly labels FS cells, or somatostatin (SOM), which labels the other major interneuron population in layer V. GABAergic terminals expressing α4 were observed to be juxtaposed to PV-positive (PV+) cells. A fraction of these terminals displayed PV immunoreactivity. We conclude that α4β2∗ nAChRs can produce sustained regulation of FS cells in Fr2 layer V. The effect presents a presynaptic component, whereas the somatic regulation decreases with age. These mechanisms may contribute to the nAChR-dependent stimulation of excitability during cognitive tasks as well as to the hyperexcitability caused by hyperfunctional heteromeric nAChRs in sleep-related epilepsy.
Collapse
Affiliation(s)
- Patrizia Aracri
- Department of Biotechnology and Biosciences, and NeuroMI (Milan Center of Neuroscience), University of Milano-Bicocca, piazza della Scienza 2, Milano 20126, Italy
| | - Simone Meneghini
- Department of Biotechnology and Biosciences, and NeuroMI (Milan Center of Neuroscience), University of Milano-Bicocca, piazza della Scienza 2, Milano 20126, Italy
| | - Aurora Coatti
- Department of Biotechnology and Biosciences, and NeuroMI (Milan Center of Neuroscience), University of Milano-Bicocca, piazza della Scienza 2, Milano 20126, Italy
| | - Alida Amadeo
- Department of Biosciences, University of Milano, Via Celoria 26, Milano 20133, Italy
| | - Andrea Becchetti
- Department of Biotechnology and Biosciences, and NeuroMI (Milan Center of Neuroscience), University of Milano-Bicocca, piazza della Scienza 2, Milano 20126, Italy.
| |
Collapse
|
146
|
Jiang X, Shen S, Sinz F, Reimer J, Cadwell CR, Berens P, Ecker AS, Patel S, Denfield GH, Froudarakis E, Li S, Walker E, Tolias AS. Response to Comment on “Principles of connectivity among morphologically defined cell types in adult neocortex”. Science 2016; 353:1108. [DOI: 10.1126/science.aaf6102] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 08/03/2016] [Indexed: 11/02/2022]
Affiliation(s)
- Xiaolong Jiang
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Shan Shen
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Fabian Sinz
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Jacob Reimer
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Cathryn R. Cadwell
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Philipp Berens
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Bernstein Centre for Computational Neuroscience, Tübingen, Germany
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Werner Reichardt Center for Integrative Neuroscience and Institute of Theoretical Physics, University of Tübingen, Tübingen, Germany
| | - Alexander S. Ecker
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Bernstein Centre for Computational Neuroscience, Tübingen, Germany
- Werner Reichardt Center for Integrative Neuroscience and Institute of Theoretical Physics, University of Tübingen, Tübingen, Germany
| | - Saumil Patel
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - George H. Denfield
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | | | - Shuang Li
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Edgar Walker
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Andreas S. Tolias
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Bernstein Centre for Computational Neuroscience, Tübingen, Germany
| |
Collapse
|
147
|
Yao XH, Wang M, He XN, He F, Zhang SQ, Lu W, Qiu ZL, Yu YC. Electrical coupling regulates layer 1 interneuron microcircuit formation in the neocortex. Nat Commun 2016; 7:12229. [PMID: 27510304 PMCID: PMC4987578 DOI: 10.1038/ncomms12229] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 06/15/2016] [Indexed: 02/06/2023] Open
Abstract
The coexistence of electrical and chemical synapses among interneurons is essential for interneuron function in the neocortex. However, it remains largely unclear whether electrical coupling between interneurons influences chemical synapse formation and microcircuit assembly during development. Here, we show that electrical and GABAergic chemical connections robustly develop between interneurons in neocortical layer 1 over a similar time course. Electrical coupling promotes action potential generation and synchronous firing between layer 1 interneurons. Furthermore, electrically coupled interneurons exhibit strong GABA-A receptor-mediated synchronous synaptic activity. Disruption of electrical coupling leads to a loss of bidirectional, but not unidirectional, GABAergic connections. Moreover, a reduction in electrical coupling induces an increase in excitatory synaptic inputs to layer 1 interneurons. Together, these findings strongly suggest that electrical coupling between neocortical interneurons plays a critical role in regulating chemical synapse development and precise formation of circuits.
Collapse
Affiliation(s)
- Xing-Hua Yao
- Institute of Neurobiology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Min Wang
- Institute of Neurobiology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Xiang-Nan He
- Centre for Computational Systems Biology and the School of Mathematical Sciences, Fudan University, Shanghai 200433, China
| | - Fei He
- Stem Cell Translational Research Center, Tongji Hospital, Tongji University School of Medicine, Shanghai 200092, China
| | - Shu-Qing Zhang
- Institute of Neurobiology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Wenlian Lu
- Centre for Computational Systems Biology and the School of Mathematical Sciences, Fudan University, Shanghai 200433, China
| | - Zi-Long Qiu
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and University of Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China
| | - Yong-Chun Yu
- Institute of Neurobiology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| |
Collapse
|
148
|
Sheng Y, Zhang L, Su SC, Tsai LH, Julius Zhu J. Cdk5 is a New Rapid Synaptic Homeostasis Regulator Capable of Initiating the Early Alzheimer-Like Pathology. Cereb Cortex 2016; 26:2937-51. [PMID: 26088971 PMCID: PMC4898661 DOI: 10.1093/cercor/bhv032] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cyclin-dependent kinase 5 (Cdk5) is a serine/threonine kinase implicated in synaptic plasticity, behavior, and cognition, yet its synaptic function remains poorly understood. Here, we report that physiological Cdk5 signaling in rat hippocampal CA1 neurons regulates homeostatic synaptic transmission using an unexpectedly rapid mechanism that is different from all known slow homeostatic regulators, such as beta amyloid (Aβ) and activity-regulated cytoskeleton-associated protein (Arc, aka Arg3.1). Interestingly, overproduction of the potent Cdk5 activator p25 reduces synapse density, and dynamically regulates synaptic size by suppressing or enhancing Aβ/Arc production. Moreover, chronic overproduction of p25, seen in Alzheimer's patients, induces initially concurrent reduction in synapse density and increase in synaptic size characteristic of the early Alzheimer-like pathology, and later persistent synapse elimination in intact brains. These results identify Cdk5 as the regulator of a novel rapid form of homeostasis at central synapses and p25 as the first molecule capable of initiating the early Alzheimer's synaptic pathology.
Collapse
Affiliation(s)
- Yanghui Sheng
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
- Undergraduate Class of 2011, Yuanpei Honors College, Peking University, Beijing100871, China
- Current address: Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Lei Zhang
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Susan C. Su
- Picower Institute for Learning and Memory and Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Li-Huei Tsai
- Picower Institute for Learning and Memory and Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - J. Julius Zhu
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| |
Collapse
|
149
|
Abstract
The most striking structure in the nervous system is the complex yet stereotyped morphology of the neuronal dendritic tree. Dendritic morphologies and the connections they make govern information flow and integration in the brain. The fundamental mechanisms that regulate dendritic outgrowth and branching are subjects of extensive study. In this review, we summarize recent advances in the molecular and cellular mechanisms for routing dendrites in layers and columns, prevalent organizational structures in the brain. We highlight how dendritic patterning influences the formation of synaptic circuits.
Collapse
Affiliation(s)
- Jiangnan Luo
- a Section on Neuronal Connectivity, Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development , Bethesda , MD , USA
| | - Philip G McQueen
- b Mathematical and Statistical Computing Laboratory, Office of Intramural Research, Center for Information Technology , National Institutes of Health , Bethesda , MD , USA
| | - Bo Shi
- a Section on Neuronal Connectivity, Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development , Bethesda , MD , USA ;,c Biological Sciences Graduate Program, College of Computer, Mathematical, and Natural Sciences , University of Maryland , College Park , MD , USA
| | - Chi-Hon Lee
- a Section on Neuronal Connectivity, Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development , Bethesda , MD , USA
| | - Chun-Yuan Ting
- a Section on Neuronal Connectivity, Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development , Bethesda , MD , USA
| |
Collapse
|
150
|
Jiang X, Lachance M, Rossignol E. Involvement of cortical fast-spiking parvalbumin-positive basket cells in epilepsy. PROGRESS IN BRAIN RESEARCH 2016; 226:81-126. [PMID: 27323940 DOI: 10.1016/bs.pbr.2016.04.012] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
GABAergic interneurons of the parvalbumin-positive fast-spiking basket cells subtype (PV INs) are important regulators of cortical network excitability and of gamma oscillations, involved in signal processing and cognition. Impaired development or function of PV INs has been associated with epilepsy in various animal models of epilepsy, as well as in some genetic forms of epilepsy in humans. In this review, we provide an overview of some of the experimental data linking PV INs dysfunction with epilepsy, focusing on disorders of the specification, migration, maturation, synaptic function, or connectivity of PV INs. Furthermore, we reflect on the potential therapeutic use of cell-type specific stimulation of PV INs within active networks and on the transplantation of PV INs precursors in the treatment of epilepsy and its comorbidities.
Collapse
Affiliation(s)
- X Jiang
- Université de Montréal, Montréal, QC, Canada; CHU Ste-Justine Research Center, Montréal, QC, Canada
| | - M Lachance
- CHU Ste-Justine Research Center, Montréal, QC, Canada
| | - E Rossignol
- Université de Montréal, Montréal, QC, Canada; CHU Ste-Justine Research Center, Montréal, QC, Canada.
| |
Collapse
|