アルドステロンは血管の反応性を調節する:フォスファディチルニノシトール3キナーゼ依存の酸化窒素合成酵素の活性化によって媒介される短期的な効果
Selina L Liu1, Saskia Schmuck, Jozef Z Chorazcyzewski
1Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada.
Circulation
|October 15, 2003
まとめ
アルドステロンは,血管機能に急速に影響します. それは無傷な内皮を持つ血管をリラックスさせ,無傷な内皮を持たない血管を収縮させ,血管抵抗性や心血管疾患に影響を及ぼします.
科学分野:
- 心血管生理学 心血管の生理学
- エンドクリノロジー エンドクリノロジー
- 血管生物学 血管生物学
背景:
- 新興の証拠は,アルドステロンの急速な,ノンゲノム的な効果を示唆しています.
- アルドステロンの血管反応に対する直接的な影響については,さらなる調査が必要である.
研究 の 目的:
- ラットの大動脈環におけるアルドステロンの血管反応に対する直接的な効果を調査する.
- 腸内および血管の滑らかな筋肉細胞におけるアルドステロンの細胞反応を調べる.
主な方法:
- ネズミの大動脈のリングセグメント (エンドセリウム・無傷・無欠) を利用して,血管の反応性を評価した.
- 細胞内皮細胞における酸化窒素合成酵素活性とキナーゼ活性を含む細胞信号伝達経路を研究した.
主要な成果:
- アルドステロンが衰弱したフェニルエフリン誘発の収縮は,内皮の無傷のリングで起こります.
- アルドステロンは,内皮を脱皮した血管の血管収縮を強めた.
- 内皮細胞では,アルドステロンは酸化窒素合成酵素の活性を増やし,PI3K経由でERK1/2とp70S6キナーゼを活性化させた.
結論:
- アルドステロンは,血管内皮細胞および滑らかな筋肉細胞に新しい,急速な効果を発揮します.
- これらの急速な作用は,外周血管抵抗を調節する役割を果たす可能性があります.
- 内皮機能不全におけるアルドステロン反応の変化は,心血管疾患の病原化に寄与する可能性があります.
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