肺血管紧张素转换酶。种间同源性及体内异源抗体的抑制作用。

Pulmonary angiotensin-converting enzyme. Interspecies homology and inhibition by heterologous antibody in vivo.

作者信息

Conroy J M, Hoffman H, Kirk E S, Hirzel H O, Sonnenblick E H, Soffer R L

出版信息

J Biol Chem. 1976 Aug 25;251(16):4828-32.

Abstract

Goat antibody against pure rabbit pulmonary angiotensin-converting enzyme was used to probe homology of converting enzymes from other species. Immunologically cross-reactive material was found in detergent-solubilized extracts of lung particles from rat, guinea pig, and dog by double immunodiffusion, radioimmunoassay, and inhibition of enzyme activity. No homology was demonstrable with bovine, frog, or chicken lung extracts. Antibodies from different individual goats yielded comparable estimates of homology by immunodiffusion and radioimmunoassay. In contrast, they varied greatly in extent and specificity of their inhibitory action on heterologous enzyme activity. The vasopressor effect of angiotensin I and the vasodepressor effect of bradykinin were diminished and potentiated, respectively, in rats treated with anti-rabbit enzyme antibody. A smaller but significant immune-dependent inhibition of the vasopressor response to angiotensin II was also observed.

摘要

用抗纯兔肺血管紧张素转换酶的山羊抗体来探测其他物种转换酶的同源性。通过双向免疫扩散、放射免疫测定和酶活性抑制，在大鼠、豚鼠和狗的肺颗粒去污剂溶解提取物中发现了免疫交叉反应物质。在牛、青蛙或鸡的肺提取物中未发现同源性。来自不同个体山羊的抗体通过免疫扩散和放射免疫测定得出了可比的同源性估计值。相比之下，它们对异源酶活性的抑制作用在程度和特异性上有很大差异。在用抗兔酶抗体处理的大鼠中，血管紧张素I的升压作用和缓激肽的降压作用分别减弱和增强。还观察到对血管紧张素II升压反应有较小但显著的免疫依赖性抑制。