極化細胞のトンネルを通るCa2+の流れ:基底膜のパッチを通る焦点Ca2+の入り口によって,頂点のCa2+貯蔵庫の充電
H Mogami1, K Nakano, A V Tepikin
1Medical Research Council Secretory Control Research Group, Physiological Laboratory, University of Liverpool, United Kingdom.
Cell
|January 10, 1997
まとめ
臓のアシナ細胞は,タプシガージンに敏感なポンプを介して細胞内カルシウム (Ca2+) 貯蔵庫を再充電します. このプロセスは,基底極から頂点極へのCa2+の流れを含み,細胞機能に不可欠です.
科学分野:
- 細胞生理学 細胞生理学
- カルシウムシグナル伝達
背景:
- 細胞内カルシウム (Ca2+) の貯蔵は,細胞のプロセスを調節する.
- 貯蔵庫の枯渇は,再充填のためのCa2+の入力を引き起こす.
研究 の 目的:
- 臓のアシナ細胞における細胞内Ca2+貯蔵の補充のメカニズムを調査する.
- この過程におけるエンドプラズマ網膜Ca2+ポンプの役割を明らかにする.
主な方法:
- 臓のアシナ細胞は,Ca2+フリー溶液中のアセチルコリン (ACh) で刺激された.
- Ca2+の吸収は,CaCl2.2を含むパッチクランプパイペットで制御された.
- Ca2+貯蔵庫の補充に対するタプシガーギンの効果を評価した.
主要な成果:
- Ca2+貯蔵庫の補充は,タプシガージンに敏感なCa2+ポンプに依存する,細胞溶液のCa2+上昇なしに発生しました.
- 補充後,ACH刺激は再び,アピカルポールから始まる細胞溶液Ca2+上昇を誘発した.
- 頂点貯蔵庫の補充には,基礎から頂点極へのCa2+輸送が必要です.
結論:
- エンドプラズマ網膜のCa2+ポンプは,臓のアシナ細胞のアピカルCa2+貯蔵庫を再充填するために不可欠です.
- ベースからアピカル経路を通るCa2+の移動は,貯蔵庫の再活性化に不可欠です.
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