AJP - Heart and Circulatory Physiology, Vol 234, Issue 4 447-H453, Copyright © 1978 by American Physiological Society
Hypotensive effect of [Sar1,Thr8]angiotensin II in spontaneously hypertensive sodium-depleted rats
H. Munoz-Ramirez, M. C. Khosla, F. M. Bumpus and P. A. Khairallah
Under inactin anesthesia, intravenous infusion of [Sar1,Thr8]angiotensin II
produced a hypotensive effect in young spontaneously hypertensive rats
(SHR) treated with furosemide and in mature SH rats fed a low-sodium diet.
The angiotensin antagonist also lowered blood pressure of young and mature
SH rats receiving a normal diet. Deoxycorticosterone acetate (DOCA) plus
saline reversed the hypotensive effect of [Saru,Thr8]angiotensin II in
young SH rats, but did not do so in mature SH rats. Plasma renin activity
(PRA) was not significantly changed by anesthesia. Furosemide or the
low-sodium diet significantly increased PRA in young and mature SH rats. In
contrast, DOCA plus saline significantly reduced PRA in both young and
mature SH rats. However, there was no correlation between PRA and the
action of the angiotensin II antagonist. These data suggest that the
renin-angiotensin system is involved in genetic hypertension.
