人类的肺毛细血管内皮结合的血管酶转化酶活性
S E Orfanos1, D Langleben, J Khoury
1Division of Cardiology, Jewish General Hospital, McGill University, Montreal, P.Q., Canada.
Circulation
|March 30, 1999
概括
这项研究验证了一种指标稀释技术,用于测量肺内皮血管酶转化酶 (ACE) 活性和动态 perfused毛细血管表面积 (DPCSA) 在人类中,找到一致的ACE度和传输时间.
科学领域:
- 肺部生理学 肺部生理学
- 脑内皮功能 脑内皮功能
- 酶动力学 酶动力学
背景情况:
- 肺内皮执行代谢功能,包括通过血管素转化酶 (ACE) 将血管素I转化为血管素II.
- 以前评估内皮质功能 in vivo 的方法是有限的.
- 这项研究的重点是描述肺内皮细胞的ACE活性和毛细血管表面积.
研究的目的:
- 验证一种指标稀释技术,用于估计人类动态 perfused毛细血管表面积 (DPCSA).
- 在体内鉴定肺内皮细胞的ACE活性.
- 评估人类肺部ACE分布和毛细血管传输时间的均性.
主要方法:
- 在12名成年人中使用了指标稀释技术.
- 测量了ACE基质3H--Phe-Ala-Pro (3H-BPAP) 的单通透透肺水解.
- 计算的关键参数包括%新陈代谢 (%M),v=-ln(1-M) 和Amax/Km (DPCSA指数).
主要成果:
- %M和v值在肺和右肺之间是相似的,表明均的ACE活性.
- 亚马克斯/公里/人体表面积呈现下降,这表明DPCSA的可量化的指数.
- 肺毛细血管ACE度和毛细血管过渡时间被发现是均的.
结论:
- 指标稀释技术可以可靠地评估肺内皮细胞在人体床边的ACE活性.
- 结果表明,在人类肺循环中,ACE度和毛细血管过渡时间均.
- 亚马克斯/千米作为人类肺部DPCSA的可靠和可量化的指数.
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