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Reggiani JDS, Jiang Q, Barbini M, Lutas A, Liang L, Fernando J, Deng F, Wan J, Li Y, Chen C, Andermann ML. Brainstem serotonin neurons selectively gate retinal information flow to thalamus. Neuron 2023; 111:711-726.e11. [PMID: 36584680 PMCID: PMC10131437 DOI: 10.1016/j.neuron.2022.12.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 10/10/2022] [Accepted: 12/05/2022] [Indexed: 12/30/2022]
Abstract
Retinal ganglion cell (RGC) types relay parallel streams of visual feature information. We hypothesized that neuromodulators might efficiently control which visual information streams reach the cortex by selectively gating transmission from specific RGC axons in the thalamus. Using fiber photometry recordings, we found that optogenetic stimulation of serotonergic axons in primary visual thalamus of awake mice suppressed ongoing and visually evoked calcium activity and glutamate release from RGC boutons. Two-photon calcium imaging revealed that serotonin axon stimulation suppressed RGC boutons that responded strongly to global changes in luminance more than those responding only to local visual stimuli, while the converse was true for suppression induced by increases in arousal. Converging evidence suggests that differential expression of the 5-HT1B receptor on RGC presynaptic terminals, but not differential density of nearby serotonin axons, may contribute to the selective serotonergic gating of specific visual information streams before they can activate thalamocortical neurons.
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Affiliation(s)
- Jasmine D S Reggiani
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA
| | - Qiufen Jiang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Melanie Barbini
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Andrew Lutas
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Liang Liang
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jesseba Fernando
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Fei Deng
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Beijing 100871, China
| | - Jinxia Wan
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Beijing 100871, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Beijing 100871, China
| | - Chinfei Chen
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA.
| | - Mark L Andermann
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA.
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Retinal Inputs to the Thalamus Are Selectively Gated by Arousal. Curr Biol 2020; 30:3923-3934.e9. [PMID: 32795442 DOI: 10.1016/j.cub.2020.07.065] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 06/12/2020] [Accepted: 07/21/2020] [Indexed: 12/14/2022]
Abstract
The brain can flexibly filter out sensory information in a manner that depends on behavioral state. In the visual thalamus and cortex, arousal and locomotion are associated with changes in the magnitude of responses to visual stimuli. Here, we asked whether such modulation of visual responses might already occur at an earlier stage in this visual pathway. We measured neural activity of retinal axons using wide-field and two-photon calcium imaging in awake mouse thalamus across arousal states associated with different pupil sizes. Surprisingly, visual responses to drifting gratings in retinal axonal boutons were robustly modulated by arousal level in a manner that varied across stimulus dimensions and across functionally distinct subsets of boutons. At low and intermediate spatial frequencies, the majority of boutons were suppressed by arousal. In contrast, at high spatial frequencies, boutons tuned to regions of visual space ahead of the mouse showed enhancement of responses. Arousal-related modulation also varied with a bouton's preference for luminance changes and direction or axis of motion, with greater response suppression in boutons tuned to luminance decrements versus increments, and in boutons preferring motion along directions or axes of optic flow. Together, our results suggest that differential modulation of distinct visual information channels by arousal state occurs at very early stages of visual processing, before the information is transmitted to neurons in visual thalamus. Such early filtering may provide an efficient means of optimizing central visual processing and perception across behavioral contexts.
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XiangWei W, Kannan V, Xu Y, Kosobucki GJ, Schulien AJ, Kusumoto H, Moufawad El Achkar C, Bhattacharya S, Lesca G, Nguyen S, Helbig KL, Cuisset JM, Fenger CD, Marjanovic D, Schuler E, Wu Y, Bao X, Zhang Y, Dirkx N, Schoonjans AS, Syrbe S, Myers SJ, Poduri A, Aizenman E, Traynelis SF, Lemke JR, Yuan H, Jiang Y. Heterogeneous clinical and functional features of GRIN2D-related developmental and epileptic encephalopathy. Brain 2019; 142:3009-3027. [PMID: 31504254 PMCID: PMC6763743 DOI: 10.1093/brain/awz232] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 04/30/2019] [Accepted: 05/31/2019] [Indexed: 01/08/2023] Open
Abstract
N-methyl d-aspartate receptors are ligand-gated ionotropic receptors mediating a slow, calcium-permeable component of excitatory synaptic transmission in the CNS. Variants in genes encoding NMDAR subunits have been associated with a spectrum of neurodevelopmental disorders. Here we report six novel GRIN2D variants and one previously-described disease-associated GRIN2D variant in two patients with developmental and epileptic encephalopathy. GRIN2D encodes for the GluN2D subunit protein; the GluN2D amino acids affected by the variants in this report are located in the pre-M1 helix, transmembrane domain M3, and the intracellular carboxyl terminal domain. Functional analysis in vitro reveals that all six variants decreased receptor surface expression, which may underline some shared clinical symptoms. In addition the GluN2D(Leu670Phe), (Ala675Thr) and (Ala678Asp) substitutions confer significantly enhanced agonist potency, and/or increased channel open probability, while the GluN2D(Ser573Phe), (Ser1271Phe) and (Arg1313Trp) substitutions result in a mild increase of agonist potency, reduced sensitivity to endogenous protons, and decreased channel open probability. The GluN2D(Ser573Phe), (Ala675Thr), and (Ala678Asp) substitutions significantly decrease current amplitude, consistent with reduced surface expression. The GluN2D(Leu670Phe) variant slows current response deactivation time course and increased charge transfer. GluN2D(Ala678Asp) transfection significantly decreased cell viability of rat cultured cortical neurons. In addition, we evaluated a set of FDA-approved NMDAR channel blockers to rescue functional changes of mutant receptors. This work suggests the complexity of the pathological mechanisms of GRIN2D-mediated developmental and epileptic encephalopathy, as well as the potential benefit of precision medicine.
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Affiliation(s)
- Wenshu XiangWei
- Department of Pediatrics and Pediatric Epilepsy Center, Peking University First Hospital, Beijing, China
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA
| | - Varun Kannan
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA
| | - Yuchen Xu
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Gabrielle J Kosobucki
- Department of Neurobiology, University of Pittsburgh School of Medicine and Pittsburgh Institute for Neurodegenerative Diseases, Pittsburgh PA, USA
| | - Anthony J Schulien
- Department of Neurobiology, University of Pittsburgh School of Medicine and Pittsburgh Institute for Neurodegenerative Diseases, Pittsburgh PA, USA
| | - Hirofumi Kusumoto
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA
| | - Christelle Moufawad El Achkar
- Division of Epilepsy, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Subhrajit Bhattacharya
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA
| | - Gaetan Lesca
- Service de Genetique, Centre de Reference Anomalies du Developpement, Hospices Civils de Lyon, Bron, France; INSERM U1028, CNRS UMR5292, Paris, France
- Centre de Recherche en Neurosciences de Lyon, GENDEV Team, Universite Claude Bernard Lyon 1, Bron, France; Claude Bernard Lyon I University, Lyon, France
| | - Sylvie Nguyen
- Department of Pediatric Neurology, University Hospital of Lille, and Lille Reference Centre for Rare Epileptic Disorders, Lille, France
| | - Katherine L Helbig
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jean-Marie Cuisset
- Department of Pediatric Neurology, University Hospital of Lille, and Lille Reference Centre for Rare Epileptic Disorders, Lille, France
| | | | | | - Elisabeth Schuler
- Division of Child Neurology and Inherited Metabolic Diseases, Centre for Paediatrics and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Ye Wu
- Department of Pediatrics and Pediatric Epilepsy Center, Peking University First Hospital, Beijing, China
| | - Xinhua Bao
- Department of Pediatrics and Pediatric Epilepsy Center, Peking University First Hospital, Beijing, China
| | - Yuehua Zhang
- Department of Pediatrics and Pediatric Epilepsy Center, Peking University First Hospital, Beijing, China
| | - Nina Dirkx
- Neurogenetics Group, University of Antwerp, Belgium
- Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - An-Sofie Schoonjans
- Department of Child Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Steffen Syrbe
- Division of Child Neurology and Inherited Metabolic Diseases, Centre for Paediatrics and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Scott J Myers
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA
- Center for Functional Evaluation of Rare Variants (CFERV), Emory University School of Medicine, Atlanta, GA, USA
| | - Annapurna Poduri
- Division of Epilepsy, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Elias Aizenman
- Department of Neurobiology, University of Pittsburgh School of Medicine and Pittsburgh Institute for Neurodegenerative Diseases, Pittsburgh PA, USA
| | - Stephen F Traynelis
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA
- Center for Functional Evaluation of Rare Variants (CFERV), Emory University School of Medicine, Atlanta, GA, USA
| | - Johannes R Lemke
- Institute of Human Genetics, University of Leipzig Hospitals and Clinics, Leipzig, Germany
| | - Hongjie Yuan
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA
- Center for Functional Evaluation of Rare Variants (CFERV), Emory University School of Medicine, Atlanta, GA, USA
| | - Yuwu Jiang
- Department of Pediatrics and Pediatric Epilepsy Center, Peking University First Hospital, Beijing, China
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Van Hook MJ, Nawy S, Thoreson WB. Voltage- and calcium-gated ion channels of neurons in the vertebrate retina. Prog Retin Eye Res 2019; 72:100760. [PMID: 31078724 PMCID: PMC6739185 DOI: 10.1016/j.preteyeres.2019.05.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/25/2019] [Accepted: 05/01/2019] [Indexed: 02/06/2023]
Abstract
In this review, we summarize studies investigating the types and distribution of voltage- and calcium-gated ion channels in the different classes of retinal neurons: rods, cones, horizontal cells, bipolar cells, amacrine cells, interplexiform cells, and ganglion cells. We discuss differences among cell subtypes within these major cell classes, as well as differences among species, and consider how different ion channels shape the responses of different neurons. For example, even though second-order bipolar and horizontal cells do not typically generate fast sodium-dependent action potentials, many of these cells nevertheless possess fast sodium currents that can enhance their kinetic response capabilities. Ca2+ channel activity can also shape response kinetics as well as regulating synaptic release. The L-type Ca2+ channel subtype, CaV1.4, expressed in photoreceptor cells exhibits specific properties matching the particular needs of these cells such as limited inactivation which allows sustained channel activity and maintained synaptic release in darkness. The particular properties of K+ and Cl- channels in different retinal neurons shape resting membrane potentials, response kinetics and spiking behavior. A remaining challenge is to characterize the specific distributions of ion channels in the more than 100 individual cell types that have been identified in the retina and to describe how these particular ion channels sculpt neuronal responses to assist in the processing of visual information by the retina.
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Affiliation(s)
- Matthew J Van Hook
- Truhlsen Eye Institute, Department of Ophthalmology & Visual Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - Scott Nawy
- Truhlsen Eye Institute, Department of Ophthalmology & Visual Sciences, University of Nebraska Medical Center, Omaha, NE, USA; Department Pharmacology & Experimental Neuroscience(2), University of Nebraska Medical Center, Omaha, NE, USA
| | - Wallace B Thoreson
- Truhlsen Eye Institute, Department of Ophthalmology & Visual Sciences, University of Nebraska Medical Center, Omaha, NE, USA; Department Pharmacology & Experimental Neuroscience(2), University of Nebraska Medical Center, Omaha, NE, USA.
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Singh M, George AK, Homme RP, Majumder A, Laha A, Sandhu HS, Tyagi SC. Circular RNAs profiling in the cystathionine-β-synthase mutant mouse reveals novel gene targets for hyperhomocysteinemia induced ocular disorders. Exp Eye Res 2018; 174:80-92. [PMID: 29803556 DOI: 10.1016/j.exer.2018.05.026] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/09/2018] [Accepted: 05/23/2018] [Indexed: 12/15/2022]
Abstract
Cystathionine-β-synthase (CBS) gene encodes L-serine hydrolyase which catalyzes β-reaction to condense serine with homocysteine (Hcy) by pyridoxal-5'-phosphate helps to form cystathionine which in turn is converted to cysteine. CBS resides at the intersection of transmethylation, transsulfuration, and remethylation pathways, thus lack of CBS fundamentally blocks Hcy degradation; an essential step in glutathione synthesis. Redox homeostasis, free-radical detoxification and one-carbon metabolism (Methionine-Hcy-Folate cycle) require CBS and its deficiency leads to hyperhomocysteinemia (HHcy) causing retinovascular thromboembolism and eye-lens dislocation along with vascular cognitive impairment and dementia. HHcy results in retinovascular, coronary, cerebral and peripheral vessels' dysfunction and how it causes metabolic dysregulation predisposing patients to serious eye conditions remains unknown. HHcy orchestrates inflammation and redox imbalance via epigenetic remodeling leading to neurovascular pathologies. Although circular RNAs (circRNAs) are dominant players regulating their parental genes' expression dynamics, their importance in ocular biology has not been appreciated. Progress in gene-centered analytics via improved microarray and bioinformatics are enabling dissection of genomic pathways however there is an acute under-representation of circular RNAs in ocular disorders. This study undertook circRNAs' analysis in the eyes of CBS deficient mice identifying a pool of 12532 circRNAs, 74 exhibited differential expression profile, ∼27% were down-regulated while most were up-regulated (∼73%). Findings also revealed several microRNAs that are specific to each circRNA suggesting their roles in HHcy induced ocular disorders. Further analysis of circRNAs helped identify novel parental genes that seem to influence certain eye disease phenotypes.
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Affiliation(s)
- Mahavir Singh
- Eye and Vision Science Laboratory, Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA; Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA.
| | - Akash K George
- Eye and Vision Science Laboratory, Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA; Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Rubens Petit Homme
- Eye and Vision Science Laboratory, Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA; Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Avisek Majumder
- Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Anwesha Laha
- Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Harpal S Sandhu
- Department of Ophthalmology and Visual Sciences, University of Louisville School of Medicine, Louisville, KY 40202, USA; Kentucky Lions Eye Center, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Suresh C Tyagi
- Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
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Hoerder-Suabedissen A, Hayashi S, Upton L, Nolan Z, Casas-Torremocha D, Grant E, Viswanathan S, Kanold PO, Clasca F, Kim Y, Molnár Z. Subset of Cortical Layer 6b Neurons Selectively Innervates Higher Order Thalamic Nuclei in Mice. Cereb Cortex 2018; 28:1882-1897. [PMID: 29481606 PMCID: PMC6018949 DOI: 10.1093/cercor/bhy036] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 01/25/2018] [Accepted: 01/28/2018] [Indexed: 12/16/2022] Open
Abstract
The thalamus receives input from 3 distinct cortical layers, but input from only 2 of these has been well characterized. We therefore investigated whether the third input, derived from layer 6b, is more similar to the projections from layer 6a or layer 5. We studied the projections of a restricted population of deep layer 6 cells ("layer 6b cells") taking advantage of the transgenic mouse Tg(Drd1a-cre)FK164Gsat/Mmucd (Drd1a-Cre), that selectively expresses Cre-recombinase in a subpopulation of layer 6b neurons across the entire cortical mantle. At P8, 18% of layer 6b neurons are labeled with Drd1a-Cre::tdTomato in somatosensory cortex (SS), and some co-express known layer 6b markers. Using Cre-dependent viral tracing, we identified topographical projections to higher order thalamic nuclei. VGluT1+ synapses formed by labeled layer 6b projections were found in posterior thalamic nucleus (Po) but not in the (pre)thalamic reticular nucleus (TRN). The lack of TRN collaterals was confirmed with single-cell tracing from SS. Transmission electron microscopy comparison of terminal varicosities from layer 5 and layer 6b axons in Po showed that L6b varicosities are markedly smaller and simpler than the majority from L5. Our results suggest that L6b projections to the thalamus are distinct from both L5 and L6a projections.
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Affiliation(s)
| | - Shuichi Hayashi
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - Louise Upton
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - Zachary Nolan
- Neural and Behavioral Sciences, Pennsylvania State University, 500 University Drive, Hershey, PA 17033, USA
| | - Diana Casas-Torremocha
- Department of Anatomy, Histology and Neuroscience, School of Medicine, Autónoma University, Madrid, Spain
| | - Eleanor Grant
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - Sarada Viswanathan
- Department of Biology, University of Maryland, 1116 Biosciences Building,College Park, MD 20742, USA
| | - Patrick O Kanold
- Department of Biology, University of Maryland, 1116 Biosciences Building,College Park, MD 20742, USA
| | - Francisco Clasca
- Department of Anatomy, Histology and Neuroscience, School of Medicine, Autónoma University, Madrid, Spain
| | - Yongsoo Kim
- Neural and Behavioral Sciences, Pennsylvania State University, 500 University Drive, Hershey, PA 17033, USA
| | - Zoltán Molnár
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
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Abstract
My active collaboration with Ray Guillery started in 1968, when he was a Full Professor at the University of Wisconsin and I was a graduate student at the University of Pennsylvania. The collaboration lasted almost 50 years with virtually no breaks. Among the ideas we proposed are that glutamatergic pathways in thalamus and cortex can be classified into drivers and modulators; that many thalamic nuclei could be classified as higher order, meaning that they receive driving input from layer 5 of cortex and participate in cortico-thalamocortical circuits; and that much of the information relayed by thalamus serves as an efference copy for motor commands initiated by cortex.
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Affiliation(s)
- S Murray Sherman
- Department of Neurobiology, University of Chicago, Chicago, IL, 60637, USA
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Aguila J, Cudeiro FJ, Rivadulla C. Suppression of V1 Feedback Produces a Shift in the Topographic Representation of Receptive Fields of LGN Cells by Unmasking Latent Retinal Drives. Cereb Cortex 2018; 27:3331-3345. [PMID: 28334353 DOI: 10.1093/cercor/bhx071] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Indexed: 12/15/2022] Open
Abstract
In awake monkeys, we used repetitive transcranial magnetic stimulation (rTMS) to focally inactivate visual cortex while measuring the responsiveness of parvocellular lateral geniculate nucleus (LGN) neurons. Effects were noted in 64/75 neurons, and could be divided into 2 main groups: (1) for 39 neurons, visual responsiveness decreased and visual latency increased without apparent shift in receptive field (RF) position and (2) a second group (n = 25, 33% of the recorded cells) whose excitability was not compromised, but whose RF position shifted an average of 4.5°. This change is related to the retinotopic correspondence observed between the recorded thalamic area and the affected cortical zone. The effect of inactivation for this group of neurons was compatible with silencing the original retinal drive and unmasking a second latent retinal drive onto the studied neuron. These results indicate novel and remarkable dynamics in thalamocortical circuitry that force us to reassess constraints on retinogeniculate transmission.
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Affiliation(s)
- Jordi Aguila
- Neurocom, School of Health Sciences and Centro de Investigacións Científicas Avanzadas (CICA), Institute of Biomedical Research (INIBIC), University of A Coruña, 15006 A Coruña, Spain
| | - F Javier Cudeiro
- Neurocom, School of Health Sciences and Centro de Investigacións Científicas Avanzadas (CICA), Institute of Biomedical Research (INIBIC), University of A Coruña, 15006 A Coruña, Spain.,Cerebral Stimulation Center of Galicia, 15009 A Coruña, Spain
| | - Casto Rivadulla
- Neurocom, School of Health Sciences and Centro de Investigacións Científicas Avanzadas (CICA), Institute of Biomedical Research (INIBIC), University of A Coruña, 15006 A Coruña, Spain
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Synaptic properties of the lemniscal and paralemniscal pathways to the mouse somatosensory thalamus. Proc Natl Acad Sci U S A 2017; 114:E6212-E6221. [PMID: 28696281 PMCID: PMC5544298 DOI: 10.1073/pnas.1703222114] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Somatosensory information is thought to arrive in thalamus through two glutamatergic routes called the lemniscal and paralemniscal pathways via the ventral posterior medial (VPm) and posterior medial (POm) nuclei. Here we challenge the view that these pathways functionally represent parallel information routes. Using electrical stimulation and an optogenetic approach in brain slices from the mouse, we investigated the synaptic properties of the lemniscal and paralemniscal input to VPm and POm. Stimulation of the lemniscal pathway produced class 1, or "driver," responses in VPm relay cells, which is consistent with this being an information-bearing channel. However, stimulation of the paralemniscal pathway produced two distinct types of responses in POm relay cells: class 1 (driver) responses in 29% of the cells, and class 2, or "modulator," responses in the rest. Our data suggest that, unlike the lemniscal pathway, the paralemniscal one is not homogenous and that it is primarily modulatory. This finding requires major rethinking regarding the routes of somatosensory information to cortex and suggests that the paralemniscal route is chiefly involved in modulatory functions rather than simply being an information route parallel to the lemniscal channel.
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11
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Abstract
The thalamocortical (TC) relay neuron of the dorsoLateral Geniculate Nucleus (dLGN) has borne its imprecise label for many decades in spite of strong evidence that its role in visual processing transcends the implied simplicity of the term "relay". The retinogeniculate synapse is the site of communication between a retinal ganglion cell and a TC neuron of the dLGN. Activation of retinal fibers in the optic tract causes reliable, rapid, and robust postsynaptic potentials that drive postsynaptics spikes in a TC neuron. Cortical and subcortical modulatory systems have been known for decades to regulate retinogeniculate transmission. The dynamic properties that the retinogeniculate synapse itself exhibits during and after developmental refinement further enrich the role of the dLGN in the transmission of the retinal signal. Here we consider the structural and functional substrates for retinogeniculate synaptic transmission and plasticity, and reflect on how the complexity of the retinogeniculate synapse imparts a novel dynamic and influential capacity to subcortical processing of visual information.
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Affiliation(s)
- Elizabeth Y Litvina
- Department of Neurology,F.M. Kirby Neurobiology Center,Children's Hospital, Boston,Boston,Massachusetts 02115
| | - Chinfei Chen
- Department of Neurology,F.M. Kirby Neurobiology Center,Children's Hospital, Boston,Boston,Massachusetts 02115
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12
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The Metabotropic Glutamate Receptor Subtype 1 Mediates Experience-Dependent Maintenance of Mature Synaptic Connectivity in the Visual Thalamus. Neuron 2016; 91:1097-1109. [PMID: 27545713 DOI: 10.1016/j.neuron.2016.07.035] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 04/18/2016] [Accepted: 07/19/2016] [Indexed: 11/23/2022]
Abstract
Neural circuits formed during postnatal development have to be maintained stably thereafter, but their mechanisms remain largely unknown. Here we report that the metabotropic glutamate receptor subtype 1 (mGluR1) is essential for the maintenance of mature synaptic connectivity in the dorsal lateral geniculate nucleus (dLGN). In mGluR1 knockout (mGluR1-KO) mice, strengthening and elimination at retinogeniculate synapses occurred normally until around postnatal day 20 (P20). However, during the subsequent visual-experience-dependent maintenance phase, weak retinogeniculate synapses were newly recruited. These changes were similar to those of wild-type (WT) mice that underwent visual deprivation or inactivation of mGluR1 in the dLGN from P21. Importantly, visual deprivation was ineffective in mGluR1-KO mice, and the changes induced by visual deprivation in WT mice were rescued by pharmacological activation of mGluR1 in the dLGN. These results demonstrate that mGluR1 is crucial for the visual-experience-dependent maintenance of mature synaptic connectivity in the dLGN.
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13
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Sherman SM. Thalamus plays a central role in ongoing cortical functioning. Nat Neurosci 2016; 19:533-41. [PMID: 27021938 DOI: 10.1038/nn.4269] [Citation(s) in RCA: 447] [Impact Index Per Article: 55.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 02/11/2016] [Indexed: 12/22/2022]
Abstract
Several challenges to current views of thalamocortical processing are offered here. Glutamatergic pathways in thalamus and cortex are divided into two distinct classes: driver and modulator. We suggest that driver inputs are the main conduits of information and that modulator inputs modify how driver inputs are processed. Different driver sources reveal two types of thalamic relays: first order relays receive subcortical driver input (for example, retinal input to the lateral geniculate nucleus), whereas higher order relays (for example, pulvinar) receive driver input from layer 5 of cortex and participate in cortico-thalamo-cortical (or transthalamic) circuits. These transthalamic circuits represent an unappreciated aspect of cortical functioning, which I discuss here. Direct corticocortical connections are often paralleled by transthalamic ones. Furthermore, driver inputs to thalamus, both first and higher order, typically arrive via branching axons, and the transthalamic branch often innervates subcortical motor centers, leading to the suggestion that these inputs to thalamus serve as efference copies.
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Affiliation(s)
- S Murray Sherman
- Department of Neurobiology, University of Chicago, Chicago, Illinois, USA
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14
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Jubran M, Mohar B, Lampl I. The Transformation of Adaptation Specificity to Whisker Identity from Brainstem to Thalamus. Front Syst Neurosci 2016; 10:56. [PMID: 27445716 PMCID: PMC4917531 DOI: 10.3389/fnsys.2016.00056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Accepted: 06/09/2016] [Indexed: 01/15/2023] Open
Abstract
Stimulus specific adaptation has been studied extensively in different modalities. High specificity implies that deviant stimulus induces a stronger response compared to a common stimulus. The thalamus gates sensory information to the cortex, therefore, the specificity of adaptation in the thalamus must have a great impact on cortical processing of sensory inputs. We studied the specificity of adaptation to whisker identity in the ventral posteromedial nucleus of the thalamus (VPM) in rats using extracellular and intracellular recordings. We found that subsequent to repetitive stimulation that induced strong adaptation, the response to stimulation of the same, or any other responsive whisker was equally adapted, indicating that thalamic adaptation is non-specific. In contrast, adaptation of single units in the upstream brainstem principal trigeminal nucleus (PrV) was significantly more specific. Depolarization of intracellularly recorded VPM cells demonstrated that adaptation is not due to buildup of inhibition. In addition, adaptation increased the probability of observing complete synaptic failures to tactile stimulation. In accordance with short-term synaptic depression models, the evoked synaptic potentials in response to whisker stimulation, subsequent to a response failure, were facilitated. In summary, we show that local short-term synaptic plasticity is involved in the transformation of adaptation in the trigemino-thalamic synapse and that the low specificity of adaptation in the VPM emerges locally rather than cascades from earlier stages. Taken together we suggest that during sustained stimulation, local thalamic mechanisms equally suppress inputs arriving from different whiskers before being gated to the cortex.
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Affiliation(s)
- Muna Jubran
- Department of Neurobiology, Weizmann Institute of Science Rehovot, Israel
| | - Boaz Mohar
- Department of Neurobiology, Weizmann Institute of Science Rehovot, Israel
| | - Ilan Lampl
- Department of Neurobiology, Weizmann Institute of Science Rehovot, Israel
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15
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Li Q, Cui P, Miao Y, Gao F, Li XY, Qian WJ, Jiang SX, Wu N, Sun XH, Wang Z. Activation of group I metabotropic glutamate receptors regulates the excitability of rat retinal ganglion cells by suppressing Kir and I h. Brain Struct Funct 2016; 222:813-830. [PMID: 27306787 DOI: 10.1007/s00429-016-1248-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 06/05/2016] [Indexed: 10/21/2022]
Abstract
Group I metabotropic glutamate receptor (mGluR I) activation exerts a slow postsynaptic excitatory effect in the CNS. Here, the issues of whether and how this receptor is involved in regulating retinal ganglion cell (RGC) excitability were investigated in retinal slices using patch-clamp techniques. Under physiological conditions, RGCs displayed spontaneous firing. Extracellular application of LY367385 (10 µM)/MPEP (10 µM), selective mGluR1 and mGluR5 antagonists, respectively, significantly reduced the firing frequency, suggesting that glutamate endogenously released from bipolar cells constantly modulates RGC firing. DHPG (10 µM), an mGluR I agonist, significantly increased the firing and caused depolarization of the cells, which were reversed by LY367385, but not by MPEP, suggesting the involvement of the mGluR1 subtype. Intracellular Ca2+-dependent PI-PLC/PKC and calcium/calmodulin-dependent protein kinase II (CaMKII) signaling pathways mediated the DHPG-induced effects. In the presence of cocktail synaptic blockers (CNQX, D-AP5, bicuculline, and strychnine), which terminated the spontaneous firing in both ON and OFF RGCs, DHPG still induced depolarization and triggered the cells to fire. The DHPG-induced depolarization could not be blocked by TTX. In contrast, Ba2+, an inwardly rectifying potassium channel (Kir) blocker, and Cs+ and ZD7288, hyperpolarization-activated cation channel (I h) blockers, mimicked the effect of DHPG. Furthermore, in the presence of Ba2+/ZD7288, DHPG did not show further effects. Moreover, Kir and I h currents could be recorded in RGCs, and extracellular application of DHPG indeed suppressed these currents. Our results suggest that activation of mGluR I regulates the excitability of rat RGCs by inhibiting Kir and I h.
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Affiliation(s)
- Qian Li
- Institutes of Brain Science, Fudan University, 138 Yixueyuan Rd, Shanghai, 200032, China.,Institute of Neurobiology, Fudan University, Shanghai, 200032, China.,State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China.,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Peng Cui
- Institutes of Brain Science, Fudan University, 138 Yixueyuan Rd, Shanghai, 200032, China.,Institute of Neurobiology, Fudan University, Shanghai, 200032, China.,State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China.,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Yanying Miao
- Institutes of Brain Science, Fudan University, 138 Yixueyuan Rd, Shanghai, 200032, China.,Institute of Neurobiology, Fudan University, Shanghai, 200032, China.,State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China.,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Feng Gao
- Institutes of Brain Science, Fudan University, 138 Yixueyuan Rd, Shanghai, 200032, China.,Eye & ENT Hospital, Fudan University, Shanghai, 200031, China.,State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China.,Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, 200031, China.,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Xue-Yan Li
- Institutes of Brain Science, Fudan University, 138 Yixueyuan Rd, Shanghai, 200032, China.,Institute of Neurobiology, Fudan University, Shanghai, 200032, China.,State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China.,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Wen-Jing Qian
- Institutes of Brain Science, Fudan University, 138 Yixueyuan Rd, Shanghai, 200032, China.,Institute of Neurobiology, Fudan University, Shanghai, 200032, China.,State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China.,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Shu-Xia Jiang
- Institutes of Brain Science, Fudan University, 138 Yixueyuan Rd, Shanghai, 200032, China.,Institute of Neurobiology, Fudan University, Shanghai, 200032, China.,State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China.,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Na Wu
- Institutes of Brain Science, Fudan University, 138 Yixueyuan Rd, Shanghai, 200032, China.,Eye & ENT Hospital, Fudan University, Shanghai, 200031, China.,State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China.,Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, 200031, China.,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Xing-Huai Sun
- Institutes of Brain Science, Fudan University, 138 Yixueyuan Rd, Shanghai, 200032, China. .,Eye & ENT Hospital, Fudan University, Shanghai, 200031, China. .,State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China. .,Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, 200031, China. .,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China.
| | - Zhongfeng Wang
- Institutes of Brain Science, Fudan University, 138 Yixueyuan Rd, Shanghai, 200032, China. .,Eye & ENT Hospital, Fudan University, Shanghai, 200031, China. .,Institute of Neurobiology, Fudan University, Shanghai, 200032, China. .,State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China. .,Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, 200031, China. .,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China.
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16
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Abstract
Corticothalamic projection systems arise from 2 main cortical layers. Layer V neurons project exclusively to higher-order thalamic nuclei, while layer VIa fibers project to both first-order and higher-order thalamic nuclei. During early postnatal development, layer VIa and VIb fibers accumulate at the borders of the dorsal lateral geniculate nucleus (dLGN) before they innervate it. After neonatal monocular enucleation or silencing of the early retinal activity, there is premature entry of layer VIa and VIb fibers into the dLGN contralateral to the manipulation. Layer V fibers do not innervate the superficial gray layer of the superior colliculus during the first postnatal week, but also demonstrate premature entry to the contralateral superficial gray layer following neonatal enucleation. Normally, layer V driver projections to the thalamus only innervate higher-order nuclei. Our results demonstrate that removal of retinal input from the dLGN induces cortical layer V projections to aberrantly enter, arborize, and synapse within the first-order dLGN. These results suggest that there is cross-hierarchical corticothalamic plasticity after monocular enucleation. Cross-hierarchical rewiring has been previously demonstrated in the thalamocortical system (Pouchelon et al. 2014), and now we provide evidence for cross-hierarchical corticothalamic rewiring after loss of the peripheral sensory input.
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Affiliation(s)
- Eleanor Grant
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | | | - Zoltán Molnár
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
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17
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Petrof I, Viaene AN, Sherman SM. Properties of the primary somatosensory cortex projection to the primary motor cortex in the mouse. J Neurophysiol 2015; 113:2400-7. [PMID: 25632081 PMCID: PMC4416606 DOI: 10.1152/jn.00949.2014] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 01/22/2015] [Indexed: 11/22/2022] Open
Abstract
The primary somatosensory (S1) and primary motor (M1) cortices are reciprocally connected, and their interaction has long been hypothesized to contribute to coordinated motor output. Very little is known, however, about the nature and synaptic properties of the S1 input to M1. Here we wanted to take advantage of a previously developed sensorimotor slice preparation that preserves much of the S1-to-M1 connectivity (Rocco MM, Brumberg JC. J Neurosci Methods 162: 139-147, 2007), as well as available optogenetic methodologies, in order to investigate the synaptic profile of this projection. Our data show that S1 input to pyramidal cells of M1 is highly homogeneous, possesses many features of a "driver" pathway, such as paired-pulse depression and lack of metabotropic glutamate receptor activation, and is mediated through axons that terminate in both small and large synaptic boutons. Our data suggest that S1 provides M1 with afferents that possess synaptic and anatomical characteristics ideal for the delivery of strong inputs that can "drive" postsynaptic M1 cells, thereby potentially affecting their output.
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Affiliation(s)
- Iraklis Petrof
- Department of Neurobiology, University of Chicago, Chicago, Illinois
| | - Angela N Viaene
- Department of Neurobiology, University of Chicago, Chicago, Illinois
| | - S Murray Sherman
- Department of Neurobiology, University of Chicago, Chicago, Illinois
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18
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Liu T, Petrof I, Sherman SM. Modulatory effects of activation of metabotropic glutamate receptors on GABAergic circuits in the mouse thalamus. J Neurophysiol 2015; 113:2646-52. [PMID: 25652932 DOI: 10.1152/jn.01014.2014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 02/01/2015] [Indexed: 11/22/2022] Open
Abstract
Metabotropic glutamate receptors (mGluRs) are widely distributed in the central nervous system and modulate the release of neurotransmitters in different ways. We have previously shown that activation of presynaptic group II mGluRs reduces the gain of GABAergic inputs in both primary visual and auditory cortices (V1 and A1). In the present study, we sought to determine whether activation of mGluRs can also affect the inhibitory inputs in thalamus. Using whole cell recordings in a mouse slice preparation, we studied two GABAergic inputs to thalamic relay cells: that of the thalamic reticular nucleus (TRN) to cells of the ventral posteromedial nucleus (VPM) and that of interneurons to cells of the lateral geniculate nucleus (LGN). We found that activation of mGluRs significantly reduced the amplitudes of inhibitory postsynaptic currents (IPSCs) evoked from TRN inputs to VPM cells, and further experiments indicated that this was due to activation of presynaptic group I and group II mGluRs. Similar results were found in the interneuronal inputs to LGN cells. Activation of presynaptic group I (type 1 but not type 5) and group II mGluRs significantly reduced the amplitudes of evoked IPSCs of the axonal inputs to relay cells, and additional experiments were consistent with previous observations that activation of type 5 mGluRs on the dendritic terminals of interneurons enhanced postsynaptic IPSCs. We concluded that group I and II mGluRs may generally reduce the amplitude of evoked GABAergic IPSCs of axonal inputs to thalamic relay cells, operating through presynaptic mechanisms, and this extends our previous findings in cortex.
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Affiliation(s)
- Tingting Liu
- Department of Neurobiology, University of Chicago, Chicago, Illinois
| | - Iraklis Petrof
- Department of Neurobiology, University of Chicago, Chicago, Illinois
| | - S Murray Sherman
- Department of Neurobiology, University of Chicago, Chicago, Illinois
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19
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Ohi Y, Kimura S, Haji A. Modulation of glutamatergic transmission by metabotropic glutamate receptor activation in second-order neurons of the guinea pig nucleus tractus solitarius. Brain Res 2014; 1581:12-22. [DOI: 10.1016/j.brainres.2014.04.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 04/10/2014] [Accepted: 04/23/2014] [Indexed: 11/30/2022]
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20
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Shostak Y, Wenger A, Mavity-Hudson J, Casagrande VA. Metabotropic glutamate receptor 5 shows different patterns of localization within the parallel visual pathways in macaque and squirrel monkeys. Eye Brain 2014; 6:29-43. [PMID: 25774086 PMCID: PMC4356996 DOI: 10.2147/eb.s51817] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Glutamate is used as an excitatory neurotransmitter by the koniocellular (K), magnocellular (M), and parvocellular (P) pathways to transfer signals from the primate lateral geniculate nucleus (LGN) to primary visual cortex (V1). Glutamate acts through both fast ionotropic receptors, which appear to carry the main sensory message, and slower, modulatory metabotropic receptors (mGluRs). In this study, we asked whether mGluR5 relates in distinct ways to the K, M, and P LGN axons in V1. To answer this question, we used light microscopic immunocytochemistry and preembedding electron microscopic immunogold labeling to determine the localization of mGluR5 within the layers of V1 in relation to the K, M, and P pathways in macaque and squirrel monkeys. These pathways were labeled separately via wheat germ agglutinin-horseradish peroxidase (WGA-HRP) injections targeting the LGN layers. mGluR5 is of interest because it: 1) has been shown to be expressed in the thalamic input layers; 2) appears to be responsible for some types of oscillatory firing, which could be important in the binding of visual features; and 3) has been associated with a number of sensory-motor gating-related pathologies, including schizophrenia and autism. Our results demonstrated the presence of mGluR5 in the neuropil of all V1 layers. This protein was lowest in IVCα (M input) and the infragranular layers. In layer IVC, mGluR5 also was found postsynaptic to about 30% of labeled axons, but the distribution was uneven, such that postsynaptic mGluR5 label tended to occur opposite smaller (presumed P), and not larger (presumed M) axon terminals. Only in the K pathway in layer IIIB, however, was mGluR5 always found in the axon terminals themselves. The presence of mGluR5 in K axons and not in M and P axons, and the presence of mGluR5 postsynaptic mainly to smaller P and not larger M axons suggest that the response to the release of glutamate is modulated in distinct ways within and between the parallel visual pathways of primates.
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Affiliation(s)
- Yuri Shostak
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA ; Foreign Trade Unitary Enterprise, Minsk, Belarus
| | - Ashley Wenger
- Undergraduate Neuroscience Program, Vanderbilt University, Nashville, TN, USA
| | - Julia Mavity-Hudson
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
| | - Vivien A Casagrande
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA ; Department of Psychology, Vanderbilt University, Nashville, TN, USA ; Department of Ophthalmology and Visual Sciences, Vanderbilt University, Nashville, TN, USA
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