Discrepancy between antihypertensive effect and angiotensin converting enzyme inhibition by captopril

B Waeber, H R Brunner, D B Brunner, A L Curtet, G A Turini, H Gavras
1980 Hypertension  
Captopril, an inhibitor of angiotensin conTerting enzyme, was administered twice daily to 13 hypertensive patients for a mean period of 9 weeks. Continuous blood pressure control in the ambulatory patients was established with a portable Mood pressure recorder. Notwithstanding, in eight patients with normal renal function, plasma converting enzyme was found to resume normal activity before administration of the morning dose of captopril. Only in 5 patients with impaired renal function did some
more » ... function did some blockade of plasma converting enzyme persist for more than 12 hours. Measured plasma converting enzyme activity seemed to reflect total conversion of angiotensin I, including conversion in the pulmonary vascular bed, since changes in its activity were closely paralleled by changes in plasma aldosterone levels. Bradyklnin accumulation seems unlikely when converting enzyme and thus, presumably, klninase II has resumed normal activity. Captopril administration does not seem to alter plasma epinephrine or norepinephrine levels. Blood pressure reduction in the face of normal angiotensin converting enzyme activity is probably due to hyporesponsiveness of the arterioies to pressor hormones, which may be due to specific renin-rdated and/or nonspecific effects of captopril. (Hypertension 2: 236-242, 1980) KEYWORDS • captopril • converting enzyme activity • angiotensin • bradykinln renin-angiotensln-aldosterone system • plasma catecholamines
doi:10.1161/01.hyp.2.2.236 pmid:6247269 fatcat:7z2cqsvo6nfwzm57nvhcbff7w4