AJP - Renal Physiology, Vol 253, Issue 6 1223-F1231, Copyright © 1987 by American Physiological Society
Effects of aortic constriction and renal denervation in DOCA-hypertensive swine
E. J. Zambraski and C. D. Ciccone
Department of Biology, Rutgers University, New Brunswick, New Jersey 08903.
The autoregulation of renal blood flow (RBF) and glomerular filtration rate
(GFR) was examined in normal and deoxycorticosterone acetate
(DOCA)-hypertensive Yucatan miniature swine (YMS). Aortic constriction (AC)
was used to vary renal perfusion pressure (RPP) from 158 to 90 mmHg for
DOCA-YMS and 124 to 50 mmHg for normals. DOCA animals had calculated RBF
autoregulatory indexes demonstrating less effective autoregulation compared
with controls. Over the pressure range of RBF autoregulation, control
animals also autoregulated their GFR, whereas most DOCA animals did not.
When renal function in DOCA-YMS was evaluated at the normotensive RPP of
115 mmHg, GFR, urine volume, and sodium excretion were decreased by
approximately 60, 70, and 80%, respectively. In DOCA-YMS, after the
normalization of RPP to 115 mmHg, renal denervation significantly increased
RBF. In DOCA animals the relative decrease in sodium and water excretion in
relation to decreased RPP was not altered by renal denervation. In this
hypertensive model the excretion of water and sodium are closely linked to
RPP. At a normotensive RPP the sodium retention in the DOCA animals may be
even further exaggerated by their inability to autoregulate GFR.
