人間の肺毛細血管内皮に結合したアンジオテンシン変換酵素の活性
S E Orfanos1, D Langleben, J Khoury
1Division of Cardiology, Jewish General Hospital, McGill University, Montreal, P.Q., Canada.
Circulation
|March 30, 1999
まとめ
この研究は,ヒトにおける肺内皮アンジオテンシン変換酵素 (ACE) 活性と動的に perfused毛細血管表面積 (DPCSA) を測定するためのインジケーター-希釈技術を検証し,一貫したACE濃度とトランジット時間を発見します.
科学分野:
- 肺の生理学について
- 内皮の機能は,内皮の機能である.
- 酵素の動力学について
背景:
- 肺内皮は,アンジオテンシン変換酵素 (ACE) を通してアンジオテンシンIをアンジオテンシンIIに変換することを含む代謝機能を果たします.
- 以前のインビョ内皮機能の評価方法は限られていた.
- この研究は,肺内皮のACE活動と毛細血管の表面積の特徴に重点を置いています.
研究 の 目的:
- 人体における動的に perfused毛細血管表面積 (DPCSA) を推定するためのインジケーター-希釈技術を検証する.
- 肺内皮のACE活性 in vivoを特徴付けるために.
- 人間の肺におけるACE分布と毛細血管通過時間の均一性を評価する.
主な方法:
- 12人の成人の被験者にインジケーターの希釈技術を使用した.
- ACE基質3H-ベンゾイル-フェ-アラ-プロ (3H-BPAP) の単一通路トランスプルモナリー水解を測定した.
- 計算された主要なパラメータには,%代謝 (%M),v=-ln(1-M),およびAmax/Km (DPCSAのインデックス) が含まれています.
主要な成果:
- %M と v の値は,両肺と右肺の間で類似しており,均質な ACE 活性を示しています.
- Amax/Km per body surface areaは減少を示し,DPCSA.の量化可能な指数を示唆しました.
- 肺毛細血管のACE濃度と毛細血管通過時間は均質であることが判明しました.
結論:
- インジケーター稀释技術は,ヒトのベッドサイドでの肺内皮のACE活性を確実に評価することができます.
- この結果は,ヒトの肺循環の中で,均一なACE濃度と毛細血管通過時間を示唆しています.
- Amax/Kmは,ヒトの肺におけるDPCSAの信頼性と量化可能な指標として機能します.
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