胃腺細胞の異常な浸透性特性
S J Waisbren1, J P Geibel, I M Modlin
1Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut 06510.
Nature
|March 24, 1994
まとめ
胃内膜は,消化から身を守ります. 粘液の障壁がないより深い胃腺細胞は,アンモニアと二酸化炭素を除外する頂上障壁によって酸から保護されています.
科学分野:
- 生理学 生理学とは
- 細胞生物学 細胞生物学
- 胃腸内科 胃腸内科
背景:
- 胃は消化ジュースを分泌し,自己消化について疑問を投げかけます.
- 粘液-バイカーボネートバリアは,胃の光と表面腺を保護します.
- より深い胃腺の細胞は, parietal と chief 細胞のように,この粘液の障壁を欠いており,保護の課題となっています.
研究 の 目的:
- 自己消化に対するより深い胃腺細胞の保護機構を調査する.
- 胃腺の頂上壁がアンモニア (NH3) と二酸化炭素 (CO2) を排除しているかどうかを判断する.
主な方法:
- ウサギの単一胃腺を perfusedして利用した.
- 極度の光酸化に対する細胞内pH抵抗を評価した.
- 細胞膜のアンモニアと二酸化炭素への浸透性を研究した.
主要な成果:
- 細胞内pHは,重度の光の酸性化に対するユニークな耐性を示した.
- 胃腺の頂上障壁は,アンモニアと二酸化炭素を排除することが判明しました.
- 細胞膜は,アピカルバリアとは異なり,一般的にアンモニアと二酸化炭素に対する高透過性を示す.
結論:
- 胃腺の頂上壁は,頭部および頭部細胞を含むより深い細胞に保護を提供します.
- この障壁がアンモニアと二酸化炭素を排除することで,分泌される胃酸と酵素による細胞損傷を防ぐことができます.
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