オオニシ ジュンジ  onishi junji
大西 淳之

  • 所属   東京家政大学  家政学部 栄養学科
  •     東京家政大学大学院  人間生活学総合研究科 健康栄養学専攻
  •     東京家政大学大学院  人間生活学総合研究科 人間生活学専攻
  •     東京家政大学短期大学部  短期大学部 栄養科
  • 職種   教授
論文種別 原著
言語種別 英語
査読の有無 査読あり
表題 Characterization of recombinant endothelin receptor-type B overexpressed in Chinese-hamster ovary cells.
掲載誌名 正式名:Biomedical Research (Tokyo, Japan)
略  称:Biomed Res
ISSNコード:03886107/1880313x
掲載区分国内
巻・号・頁 15(5),pp.299-309
著者・共著者 ◎Etoh N, Kondoh M, Ohnishi J, Murakami K, Miyazaki H
発行年月 1994
概要 The recombinant B type of endothelin (ET) receptor (ETB receptor) was expressed at high levels in Chinese hamster ovary (CHO) cells. The recombinant ETB receptor possessed biochemical characteristics of the endogenous ETB receptor with regard to affinities, specificities for ET isopeptides, and molecular mass. In the transfected CHO cells, high concentrations of ET (10-10 M≦) caused a rapid, transient increase in intracellular free Ca2+ concentrations ([Ca2+]i) followed by a lower, sustained phase. In contrast, low concentrations of ET (≦10-11 M) induced only the sustained [Ca2+]i phase. Removal ofextracellular Ca2+ and the addition of nicardipine, an antagonist of L-type Ca2+ channels, completely blocked and significantly decreased the sustained [Ca2+]i response, respectively. These results in conjunction with the findings that ET-induced inositol triphosphate production was observed at only high concentrations of ET (10-10 M≦) suggest that the ETB receptor preferentially couples with the induction of Ca2+ channel opening at low ligand concentrations (≦10-11 M), whereas that the receptor causes both activation of phospholipase C and Ca2+ channel opening at high ligand concentrations (10-10 M≦). Rapid internalization ofthe ET-ETB receptor complex with a halftime of l5 min was detected by affinity labeling, presenting the necessity for studying correlation between the internalization and ETB receptor-mediated generation of intracellular signals. Finally, this study demonstrates the usefulness of our transfected CHO cells stably expressing the recombinant ETB receptor, with which signal transduction pathways through this receptor and internalization of the ET-ETB receptor complex can be analyzed.
DOI doi: http://doi.org/10.2220/biomedres.15.299