孤立したヒト肺における内生性酸化窒素の基礎および刺激された放出による血液動力学的効果
G Cremona1, T W Higenbottam, E A Bower
1Pulmonary Division, "Salvatore Maugeri" Foundation IRCCS, Medical Centre, Veruno, Italy.
Circulation
|September 24, 1999
まとめ
肺高血圧の肺では,内皮の酸化窒素 (NO) の放出が妨げられるが,基礎のNO放出は機能的であり続ける. この研究では,NOを調査した.
科学分野:
- 心血管科学 心血管科学
- 肺内医学は肺内医学である.
- 血管生物学 血管生物学
背景:
- 肺高血圧 (PH) は,肺の血管系に影響を与える重篤な状態です.
- 内皮の酸化窒素 (NO) は,肺血管トーンを調節する上で重要な役割を果たします.
- 機能不全のNO経路は,PHの病理生理学に関連しています.
研究 の 目的:
- 重度の肺高血圧 (SPH) と慢性閉塞性肺疾患 (COLD) の患者からの拡張肺におけるNO経路調節に対する血液動力学的反応を,ノルモテンシブ対照と比較するために.
- 異なる肺疾患における基礎および刺激された内皮酸化窒素 (NO) 放出の両方の機能的状態を調査する.
主な方法:
- SPH,COLD,および対照群から分離された充血肺を使用しました.
- 血液動力学的反応は,NO合成の抑制 (N(G) - ニトロ-L-アルギニンメチルエステル) とNO放出の刺激 (アセチルコリン,ナトリウムニトロプロシド) 時に測定されました.
- 血管反応を評価するために,肺動脈圧 (PAP) の変化を分析した.
主要な成果:
- NO合成の阻害は,すべてのグループでベースラインPAPの同様の増加を引き起こし,基礎NO放出が保存されていることを示しました.
- アセチルコリンでNOの放出を刺激すると,対照群と比較して,SPHとCOLDの肺におけるPAPの減少が著しく減少しました.
- ナトリウムニトロプロシドは,すべての肺群でPAPを効果的に減少させ,外因的なNOに対する滑らかな筋肉の反応性を確認しました.
結論:
- 刺激された内皮の窒素酸化物 (NO) 放出は,プレクソゲン性または低血圧性肺高血圧の肺動脈に障害がある.
- 基礎的なNO放出は,重度の肺高血圧でも維持されているようです.
- これらの発見は,PH肺における刺激されたNO経路の特定の欠陥を示唆しています.
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