非リン酸化性イノシトール三酸塩によるCa2+のアシナ細胞への侵入の活性化
G S Bird1, M F Rossier, A R Hughes
1Calcium Regulation Section, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709.
Nature
|July 21, 1991
まとめ
イノシトール1,4,5-トリスホスファートは,カルシウム (Ca2+) がマウスの涙状アシナ細胞に侵入するために不可欠です. この発見は,細胞カルシウムシグナル伝達経路におけるイノシトールフォスファートの役割を明確にします.
科学分野:
- 細胞生物学 細胞生物学
- 生理学 生理学とは
- バイオケミストリー バイオケミストリー
背景:
- 受容体の活性化は,細胞内カルシウム (Ca2+) の放出と,その後のプラズマ膜への侵入を誘発する.
- イノシトール1,4,5-トリスホスファートは初期Ca2+の放出を媒介するが,Ca2+の侵入におけるその役割は議論されている.
研究 の 目的:
- イノシトール1,4,5-トリスホスファートのマウスの涙状アシナ細胞にCa2+の侵入を調節する役割について調査する.
- イノシトール1,4,5-トリスホスファートが受容体活性化Ca2+エントリーに必要で十分かどうかを判断する.
主な方法:
- イノシトール・フォスファートは,マイクロインジェクションまたはパッチ・クランプ・パーフュージョンを用いてマウスの涙状アシナ細胞に導入されました.
- 細胞内自由カルシウム濃度は,Fura-2光を用いて測定された.
- カルシウム活性化カリウムチャネルは,全細胞のCa2+活動を監視した.
主要な成果:
- イノシトール1,4,5-トリスホスファートは,受容体活性化Ca2+のエントリーに必要かつ十分であることが判明しました.
- これらの発見は,マイクロインジェクションとパッチクランプの両方の実験セットアップに一貫していました.
結論:
- イノシトール1,4,5-トリスホスファートは,カルシウム (Ca2+) が血膜を横断して侵入することを開始するための重要な信号として作用します.
- この研究は,細胞のカルシウムホメオスタシスにおけるイノシトール1,4,5-トリスホスファートの役割をめぐる論争を解決しています.
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