{"title":"不同类型齿状回中间神经元的突触后 GABAB 受体介导电流","authors":"Claudius E. Degro, Imre Vida, Sam A. Booker","doi":"10.1002/hipo.23628","DOIUrl":null,"url":null,"abstract":"<p>The processing of rich synaptic information in the dentate gyrus (DG) relies on a diverse population of inhibitory GABAergic interneurons to regulate cellular and circuit activity, in a layer-specific manner. Metabotropic GABA<sub>B</sub>-receptors (GABA<sub>B</sub>Rs) provide powerful inhibition to the DG circuit, on timescales consistent with behavior and learning, but their role in controlling the activity of interneurons is poorly understood with respect to identified cell types. We hypothesize that GABA<sub>B</sub>Rs display cell type-specific heterogeneity in signaling strength, which will have direct ramifications for signal processing in DG networks. To test this, we perform <i>in vitro</i> whole-cell patch-clamp recordings from identified DG principal cells and interneurons, followed by GABA<sub>B</sub>R pharmacology, photolysis of caged GABA, and extracellular stimulation of endogenous GABA release to classify the cell type-specific inhibitory potential. Based on our previous classification of DG interneurons, we show that postsynaptic GABA<sub>B</sub>R-mediated currents are present on all interneuron types albeit at different amplitudes, dependent largely on soma location and synaptic targets. GABA<sub>B</sub>Rs were coupled to inwardly-rectifying K+ channels that strongly reduced the excitability of those interneurons where large currents were observed. These data provide a systematic characterization of GABA<sub>B</sub>R signaling in the rat DG to provide greater insight into circuit dynamics.</p>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 10","pages":"551-562"},"PeriodicalIF":2.4000,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23628","citationCount":"0","resultStr":"{\"title\":\"Postsynaptic GABAB-receptor mediated currents in diverse dentate gyrus interneuron types\",\"authors\":\"Claudius E. Degro, Imre Vida, Sam A. Booker\",\"doi\":\"10.1002/hipo.23628\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>The processing of rich synaptic information in the dentate gyrus (DG) relies on a diverse population of inhibitory GABAergic interneurons to regulate cellular and circuit activity, in a layer-specific manner. Metabotropic GABA<sub>B</sub>-receptors (GABA<sub>B</sub>Rs) provide powerful inhibition to the DG circuit, on timescales consistent with behavior and learning, but their role in controlling the activity of interneurons is poorly understood with respect to identified cell types. We hypothesize that GABA<sub>B</sub>Rs display cell type-specific heterogeneity in signaling strength, which will have direct ramifications for signal processing in DG networks. To test this, we perform <i>in vitro</i> whole-cell patch-clamp recordings from identified DG principal cells and interneurons, followed by GABA<sub>B</sub>R pharmacology, photolysis of caged GABA, and extracellular stimulation of endogenous GABA release to classify the cell type-specific inhibitory potential. Based on our previous classification of DG interneurons, we show that postsynaptic GABA<sub>B</sub>R-mediated currents are present on all interneuron types albeit at different amplitudes, dependent largely on soma location and synaptic targets. GABA<sub>B</sub>Rs were coupled to inwardly-rectifying K+ channels that strongly reduced the excitability of those interneurons where large currents were observed. These data provide a systematic characterization of GABA<sub>B</sub>R signaling in the rat DG to provide greater insight into circuit dynamics.</p>\",\"PeriodicalId\":13171,\"journal\":{\"name\":\"Hippocampus\",\"volume\":\"34 10\",\"pages\":\"551-562\"},\"PeriodicalIF\":2.4000,\"publicationDate\":\"2024-08-13\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23628\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Hippocampus\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1002/hipo.23628\",\"RegionNum\":3,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"NEUROSCIENCES\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Hippocampus","FirstCategoryId":"3","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/hipo.23628","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"NEUROSCIENCES","Score":null,"Total":0}
Postsynaptic GABAB-receptor mediated currents in diverse dentate gyrus interneuron types
The processing of rich synaptic information in the dentate gyrus (DG) relies on a diverse population of inhibitory GABAergic interneurons to regulate cellular and circuit activity, in a layer-specific manner. Metabotropic GABAB-receptors (GABABRs) provide powerful inhibition to the DG circuit, on timescales consistent with behavior and learning, but their role in controlling the activity of interneurons is poorly understood with respect to identified cell types. We hypothesize that GABABRs display cell type-specific heterogeneity in signaling strength, which will have direct ramifications for signal processing in DG networks. To test this, we perform in vitro whole-cell patch-clamp recordings from identified DG principal cells and interneurons, followed by GABABR pharmacology, photolysis of caged GABA, and extracellular stimulation of endogenous GABA release to classify the cell type-specific inhibitory potential. Based on our previous classification of DG interneurons, we show that postsynaptic GABABR-mediated currents are present on all interneuron types albeit at different amplitudes, dependent largely on soma location and synaptic targets. GABABRs were coupled to inwardly-rectifying K+ channels that strongly reduced the excitability of those interneurons where large currents were observed. These data provide a systematic characterization of GABABR signaling in the rat DG to provide greater insight into circuit dynamics.
期刊介绍:
Hippocampus provides a forum for the exchange of current information between investigators interested in the neurobiology of the hippocampal formation and related structures. While the relationships of submitted papers to the hippocampal formation will be evaluated liberally, the substance of appropriate papers should deal with the hippocampal formation per se or with the interaction between the hippocampal formation and other brain regions. The scope of Hippocampus is wide: single and multidisciplinary experimental studies from all fields of basic science, theoretical papers, papers dealing with hippocampal preparations as models for understanding the central nervous system, and clinical studies will be considered for publication. The Editor especially encourages the submission of papers that contribute to a functional understanding of the hippocampal formation.