2026-03-06T20:34:34Z https://ir.soken.ac.jp/oai

oai:ir.soken.ac.jp:00001165 2023-06-20T16:07:47Z 2:430:22

Quantitative localization of GABAA receptor subunits on hippocampal pyramidal cells by SDS-digested freeze fracture replica labeling(SDS-FRL) Quantitative localization of GABAA receptor subunits on hippocampal pyramidal cells by SDS-digested freeze fracture replica labeling(SDS-FRL) 春日井, 雄 カスガイ, ユウ KASUGAI, Yu 総合研究大学院大学 博士（理学） Pyramidal cells in he hippocampal CA1 area express at least 14 subunits of the<br />GABA-A receptor, and receive GABAergic input from interneurons, which make<br />synapses on the soma,dendrites and the axon initial segment(AIS).Here,they used<br />the SDS-digested freeze-fracture replica labelling method to visualize the cell surface<br />distribution of the alpha1,alpha2,and beta2/3 subunits quantitatively on distinct<br />subcellular compartments of pyramidal cells. Immunogold particles for these subunits<br />were accumulated over clusters of intramembrane particles(IMP) on the protoplasmic<br />face(P-face) of the plasma membrane, indicating that many IMP clusters of a certain<br />size represent GABAergic synapses.<br />The sizes of labelled synapses were not different on the somata and the main apical<br />dendritic trunks.However,the synaptic areas on AISs were significantly smaller than<br />those on the soma and apical dendrites. Axon initial segments were identified by<br />immunogold Labelling for the Nav1.6 subunit of sodium channels. The synaptic<br />receptor labelling densities for GABA-A receptor subunits were not significantly<br />different on the tested areas of the cells. A high proportion of receptor labelling was on<br />the extrasynaptic membrane of the pyramidal cell soma and dendrites. To examine the<br />co-localization of different GABA-A receptor subunits in single synapses on the soma,<br />double labelling was performed with antibodies raised in different species. These<br />experiments showed that the majority of synapses contains alpha1,alpha2,and beta2/3<br />subunits. Future experiments aim at testing whether distinct synapese populations<br />differing in the relative proportions of different subunits can be detected with freeze<br />fracture replica immunogold labelling. application/pdf 総研大甲第963号 thesis 2006-03-24 application/pdf application/pdf https://ir.soken.ac.jp/record/1165/files/甲963_要旨.pdf https://ir.soken.ac.jp/record/1165/files/甲963_本文.pdf https://ir.soken.ac.jp/records/1165 eng