AJP - Endocrinology and Metabolism, Vol 246, Issue 1 84-E88, Copyright © 1984 by American Physiological Society
Renin-angiotensin system in hypophysectomized rats. I. Control of blood pressure
C. D. Simon, T. W. Honeyman and J. C. Fray
The mechanisms whereby the pituitary gland maintains arterial pressure were
investigated in rats. The arterial pressure in hypophysectomized rats was
30 mmHg below normal. Saralasin or captopril caused a further fall of 25
and 30 mmHg, respectively, suggesting that the renin-angiotensin system
plays a role in blood pressure maintenance in hypophysectomized rats.
Growth hormone administration to hypophysectomized rats increased the
arterial pressure, but pretreatment with captopril prevented the effect.
Plasma renin activity and basal renin secretion (in vitro) was normal in
hypophysectomized rats despite a twofold greater renal renin content.
Secretory responsiveness to isoproterenol and calcium omission was lower in
hypophysectomized rats. It is concluded that the renin-angiotensin system
plays a role in maintaining arterial blood pressure in hypophysectomized
rats although the responsiveness of the system may be decreased.
