AJP - Heart and Circulatory Physiology, Vol 247, Issue 1 61-H66, Copyright © 1984 by American Physiological Society
Pathogenesis of one-kidney, one-clip hypertension in rats after renal denervation
D. Villarreal, R. H. Freeman, J. O. Davis, G. Garoutte and W. D. Sweet
This study examines the role of the renal nerves in the chronic and early
developmental stages of one-kidney, one-clip (1K-1C) Goldblatt
hypertension. Groups of uninephrectomized Sprague-Dawley rats underwent
renal artery constriction with a clip of an internal diameter of 0.23 mm
(groups 1 and 3) or 0.40 mm (groups 2 and 4) to produce severe or moderate
hypertension. Two weeks later, groups 1 and 2 were subjected to renal
denervation and groups 3 and 4 were denervated 6 and 7 wk after clipping,
respectively. In all four groups, hypertension remained unchanged during
the subsequent 2 wk after denervation. To study further the effects of
renal denervation during the early onset of hypertension, groups 5, 6, and
7 received the smaller (0.23 mm) clip after uninephrectomy. Groups 5 and 6
were renal denervated immediately before clipping; group 7 was not
denervated. In groups 6 and 7 the renin-angiotensin system was blocked with
a continuous infusion of the converting-enzyme inhibitor captopril for 24 h
before and 15 days after clipping. In group 5, renal denervation did not
prevent a prompt and severe rise in the systolic blood pressure. In groups
6 and 7, infusion of captopril prevented the hypertension only during the
first 4 days after clipping; at no time was there a difference in the
systolic blood pressure curves of groups 6 and 7 during or after captopril
infusion. These data demonstrate that regardless of the severity and
duration of hypertension, renal denervation failed to attenuate either the
development or the maintenance of 1K-1C Goldblatt hypertension in the rat.
Thus the present results fail to provide support for the concept that the
renal nerves modulate the hypertension in this experimental model.
