Hypertension, Vol 17, 270-277, Copyright © 1991 by American Heart Association
K Higashimori, J Gante, G Holzemann and T Inagami
The effects of specific renin inhibitors, angiotensin converting enzyme
inhibitors, indomethacin, and prostaglandin I2 analogue on the release of
angiotensins from isolated and Krebs-Ringer-perfused rabbit mesenteric
arteries were examined. Three different renin inhibitors suppressed release
of angiotensins in dose-dependent manners. At the highest concentration
(10(-7) M), the inhibitors EMD 52,620, EMD 54,388, and EMD 52,742 induced
46%, 52%, and 48% decreases, respectively, in the basal rate of
immunoreactive angiotensin II release. These results provide clear evidence
that released angiotensins are produced by the specific action of vascular
renin and that the renin inhibitors suppress the vascular renin-angiotensin
system as well as the circulating renin-angiotensin system and appear to
provide a useful mode for the treatment of hypertension. Nonsulfhydryl
angiotensin converting enzyme inhibitors cilazapril and delapril were more
effective than captopril, and ramipril was equipotent to captopril,
suggesting that the effectiveness of angiotensin converting enzyme
inhibitors on the vascular renin- angiotensin system cannot be explained
only by its inhibitory effect on angiotensin converting enzyme.
Indomethacin, which was reported to suppress angiotensin II release from
rat hind limbs, elicited a dose- dependent increase of angiotensin release
from rabbit mesenteric arteries. These results suggest that a difference
exists in the regulatory mechanisms in the release of angiotensins from
diverse vascular beds.
ARTICLES
Significance of vascular renin for local generation of angiotensins
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tenn 37232.
|
Hypertension Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1991 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |