Ca2+放出チャネルのサブセルラー分布は,Ca2+の波と振動を背景に,分泌外臓の振動を背景に,Ca2+放出チャネルが分布している
1Department of Physiology, Faculty of Medicine, University of Tokyo, Japan.
Cell
|August 27, 1993
まとめ
臓のアシナ細胞におけるカルシウム (Ca2+) 波はトリガーゾーンから発生し,異なる段階に分散する. イノシトール1,4,5-トリスホスファート (IP3) 受容体とCa2+放出チャネルの異質な局所化は,これらのCa2+シグナル伝達パターンを決定する.
科学分野:
- 細胞生物学 細胞生物学
- 生理学 生理学とは
背景:
- アゴニストは外分泌腺細胞を刺激し,カルシウム (Ca2+) の波と振動を誘発する.
- Ca2+シグナル伝達の空間時間的動態を理解することは,外分泌腺の機能にとって極めて重要です.
研究 の 目的:
- ネズミの臓アシナ細胞におけるCa2+波の背後にある異なる段階とメカニズムを調査する.
- Ca2+信号の開始とパターニングにおけるCa2+放出チャネルの異質な局所化の役割を特定する.
主な方法:
- コンフォカルCa2+イメージングは,Ca2+ダイナミクスをリアルタイムで視覚化するために使用されました.
- イノシトール1,4,5-トリスホスファート (IP3) とCa2+のパッチピペット注射が,受容体の機能を検査するために使用されました.
主要な成果:
- Ca2+波は,トリガーゾーン (Tゾーン) での開始,急速な拡散,および高アゴニスト濃度で基礎極への遅い伝播の3つの異なる段階を示した.
- 高感度IP3受容体はTゾーン,Ca2+誘発のCa2+放出チャネルは粒状領域,低感度IP3受容体は基礎領域に局在していた.
- TゾーンのIP3受容体は,自律的なCa2+スパイクとパターン化されたCa2+振動を開始しました.
結論:
- Ca2+放出チャネルの異質な細胞性局所化は,臓のアシナ細胞におけるCa2+波と振動パターンの重要な決定因子である.
- Tゾーンは,局所的なIP3受容体活性を通じたCa2+シグナリングイベントを開始するための重要なサイトとして機能します.
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