タケトウ　メグミ   TAKETOU MEGUMI   武藤　恵    所属   関西医科大学  生理学講座    職種   講師
言語種別	英語
発表タイトル	Function of metabotropic glutamate receptor 1 in the neonatal hippocampal marginal zone
会議名	the 97th Annual Meeting of the Physiological Society of Japan
主催者	the Physiological Society of Japan
学会区分	全国規模の学会
発表形式	抄録のみ
講演区分	一般
発表者・共同発表者	◎Megumi Taketo
発表年月日	2020/03/17
開催地 （都市, 国名）	Beppu, Japan（誌上開催）
学会抄録	J. Physiol. Sci. 70(Suppl. 1),S97 2020
概要	Metabotropic glutamate receptors (mGluRs) are distributed in the central nervous system and play important roles as synaptic plasticity and memory formation in various neuronal processes. mGluRs are classified into three groups I to III, and group I mGluRs consist of two subtypes, mGluR1 and mGluR5. Group I receptors couple to Gq protein and increase intracellular Ca2+ concentration ([Ca2+]i) through the release of Ca2+ from intracellular stores. These receptors also regulate the channel activity of plasma membranes. Hippocampal marginal zone contains early-developed neurons including Cajal-Retzius cells (CR cells), which regulate neuronal migration through secretion of glycoprotein, reelin. CR cells also project their dendrites to other hippocampal neurons and regulate network activity. Though the function of the secreted reelin has been studied considerably, less is known about the regulation of CR cell excitability. In the present experiments, functional expression of mGluR1 was detected by fluorescence Ca2+ imaging, in acute slices of neonatal rat hippocampus. In CR cells, [Ca2+]i elevation was induced by application of group 1 mGluR-specific agonist in the presence of mGluR5 specific antagonist, MPEP. Whereas, the [Ca2+]i elevation was prevented by mGluR1-specific antagonist, CPCCOEt. Characteristics of the Ca2+ mobilization after activation of mGluR1 in neurons of marginal zone were further investigated. Elimination of extracellular Ca2+ could not prevent the mGluR1-induced [Ca2+]i increase in CR cells. Effects of Ca2+-permeable channel blockers on mGluR1-mediated Ca2+ mobilization were also determined. Possibility of a cross-talk between mGluR1 and other receptors expressed in CR cells is under investigation.