脳の血流の自己調節におけるアンジオテンシンの役割
O B Paulson1, G Waldemar, A R Andersen
1Department of Neurology, Rigshospitalet (University Hospital), Copenhagen, Denmark.
Circulation
|June 1, 1988
まとめ
アンジオテンシン変換酵素阻害剤カプトプリルは,脳血流の自己調節限界を下げる. これは,カプトプリルが脳動脈を広げることで,心不全患者の脳血流を維持する方法を説明します.
科学分野:
- 神経科学は神経科学である.
- 心血管生理学 心血管の生理学
- 薬理学 薬理学とは
背景:
- レニン-アニオテンシン系 (RAS) は,血管や脳を含む腎臓外組織に存在します.
- アンジオテンシン変換酵素 (ACE) 阻害剤は,腎外RAS機能の研究を可能にする効果的な阻害剤です.
研究 の 目的:
- 脳の血流の自己調節に対するACE阻害剤の効果を調査する.
- 脳血管トーンと血流の維持における外RASの役割を明らかにする.
主な方法:
- ACE阻害剤カプトプリルを正常血圧および自発高血圧のラットに投与する.
- 脳の血流の自己調節限界の評価.
- ACE阻害剤で治療された慢性心不全患者の脳血流の臨床観察.
主要な成果:
- カプトプリルは脳血流の自己調節をシフトさせ,ネズミの血圧を下げました.
- 慢性心不全の患者は,ACE阻害による血圧低下にもかかわらず,脳血流の維持を示した.
- ACE阻害は,より大きな脳動脈の膨張につながり,血管トーンを低下させました.
結論:
- ACEの阻害は,脳血流の自己調節に好ましい影響を及ぼします.
- 外RASは,脳血管トーンを維持する上で重要な役割を果たします.
- 脳の血流に対するカプトプリルの効果は,局所アンジオテンシンIIの産生を阻害したため,血管トーンが低下することで媒介されます.
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