肺上皮細胞の1回の機械的な伸縮後にカルシウム動員とエクソサイトーシス
1Cardiovascular Research Institute, University of California, San Francisco 94143-0130.
Science (New York, N.Y.)
|November 30, 1990
まとめ
機械的な肺の伸縮は,表面活性物質を分泌するアルベオラ型II細胞を直接刺激します. このプロセスは,細胞内カルシウムの一時的な増加を含み,肺機能を調節する機械的要因を強調します.
科学分野:
- 細胞生物学 細胞生物学
- 呼吸器生理学 呼吸器生理学について
- バイオフィジックス 生物物理学
背景:
- 深肺膨張は,理解されていないメカニズムを通して表面活性物質の分泌を刺激します.
- アルベオラ型II細胞は,表面活性物質の産生と分泌を担当する.
研究 の 目的:
- 機械的な膨張がアルベオラ型II細胞からの表面活性物質の分泌を直接刺激するかどうかを調査する.
- 機械的に誘発された表面活性物質の放出における細胞内カルシウムの役割を明らかにする.
主な方法:
- 柔軟なシラスティック膜にアルベオラ型II細胞を培養する.
- 培養細胞に制御された機械的ストレッチを施す.
- 光インジケーターを用いた細胞内カルシウム濃度の測定.
- 機械的刺激後の表面活性物質の分泌量 (エクソサイトーシス) を定量化する.
主要な成果:
- 単一の機械的なストレッチは,細胞内カルシウム濃度の急速かつ一時的な上昇を誘導しました.
- このカルシウム動員に続いて,持続的な期間,表面活性物質の分泌が強化されました.
- カルシウム反応と表面活性物質の放出の両方とも,ストレッチ刺激の大きさと用量依存の関係を示した.
結論:
- 機械的な膨張は,アルベオラ型II細胞による表面活性物質の分泌の直接的な刺激である.
- 細胞内カルシウムシグナル伝達は,機械的ストレスに対する細胞の反応を媒介する上で重要な役割を果たします.
- 機械的な力は,非ニューロン,非筋肉の細胞の複雑な細胞機能を調節し,正常な肺生理に影響を与えます.
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