実験的な高コレステロール血症におけるエンドセリン媒介による冠動脈収縮の強化と基礎酸化窒素の活性低下
V Mathew1, C R Cannan, V M Miller
1Division of Cardiovascular Diseases and Internal Medicine, Mayo Foundation, Rochester, Minn 55905, USA.
Circulation
|October 10, 1997
まとめ
実験的な高コレステロール血症は冠動脈血管運動の反応を変化させる. エンドオセリン-1は血管収縮を増加させ,酸化窒素合成酵素抑制効果は低下し,冠動脈血管反応性の低下を示した.
科学分野:
- 心血管生理学 心血管の生理学
- 内皮機能の機能について
- メタボリック障害 メタボリック障害
背景:
- 実験的高コレステロール血症は冠動脈血管運動機能不全と関連しています.
- この研究では,高コレステロール血症におけるエンドセリンと酸化窒素経路に対する冠動脈血管運動応答の変化を調査した.
研究 の 目的:
- 実験的な高コレステロール血症が,エンドセリンと内生性酸化窒素 (NO) 経路の阻害に対する冠動脈血管運動反応を変化させるという仮説を検証する.
主な方法:
- エンドオセリン-1 (ET-1) とN(G) モノメチル-L-アルギニン (L-NMMA) を10週間のコレステロールダイエット前後に豚の冠動脈に注入する.
- 冠動脈血流量 (CBF),冠動脈直径 (CAD),冠動脈血管抵抗 (CVR) を測定する.
- 構成的酸化窒素合成酵素 (NOS) のET受容体密度と免疫ヒストケミカル染色の評価.
主要な成果:
- 高コレステロール血症のブタは,CBFとCADの有意に顕著な減少を示し,ET-1への反応としてCVRの増加を示しました.
- CBF,CAD,CVRに対するL-NMMAの効果は,高コレステロール血症の豚では弱まった.
- 高コレステロール血症の豚の冠動脈では,構成的なNOS免疫反応性の低下が観察されました.
結論:
- 実験的高コレステロール血症は,冠動脈血管収縮をエンドセリンに強化する.
- 高コレステロール血症では,内生的なNO活性抑制に対する反応が弱まります.
- これらの発見は,実験的な高コレステロール血症における冠動脈血管反応性の変化を示唆しています.
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