ウエタ ヨシフミ   Yoshifumi Ueta
  植田 禎史
   所属   医学部 医学科
   職種   講師
論文種別 原著
言語種別 英語
査読の有無 査読あり
表題 Homer 1a suppresses neocortex long-term depression in a cortical layer-specific manner.
掲載誌名 正式名:Journal of Neurophysiology
略  称:J Neurophysiol
ISSNコード:0022-3077(Print)0022-3077(Linking)
巻・号・頁 99(2),pp.950-957
著者・共著者 Ueta Yoshifumi†, Yamamoto Ryo, Sugiura Shigeki, Inokuchi Kaoru, Kato Nobuo*
担当区分 筆頭著者
発行年月 2008/02
概要 Homer1a/Vesl-1S is an activity-dependently induced member of the scaffold protein family Homer/Vesl, which is known to link group I metabotropic glutamate receptors (mGluRs) to endoplasmic calcium release channels and to regulate them. Here we studied roles of Homer 1a in inducing long-term depression (LTD) in rat visual cortex slices. Homer 1a protein was injected by diffusion from whole cell patch pipettes. In layer VI pyramidal cells, LTD was reduced in magnitude with Homer 1a. LTD in layer VI was suppressed by applying antagonists of mGluR5, a subtype of group I mGluRs expressed with higher density than mGluR1 in neocortex pyramidal cells, or inositol-1,4,5-triphosphate receptors (IP3Rs) but not that against N-methyl-d-aspartate receptors (NMDARs). In layer II/III or layer V, Homer 1a injection was unable to affect LTD, which is mostly dependent on NMDARs and not on group I mGluRs in these layers. To examine the effects of endogenous Homer 1a, electroconvulsive shock (ECS) was applied. Homer 1a thereby induced, as did Homer 1a injection, reduced LTD magnitude in layer VI pyramidal cells and failed to do so in layer II/III or layer V pyramidal cells. These results indicate that both exo- and endogenous Homer 1a suppressed LTD in a cortical layer-specific manner, and its layer-specificity may be explained by the high affinity of Homer 1a to group I mGluRs.
DOI 10.1152/jn.01101.2007
文献番号 18077661
PMID 18077661