Vasodilator capacity of contralateral kidney in Goldblatt hypertensive dog.

Abstract

Because of previous suggestions of impaired renal blood flow in the contralateral kidney of Goldblatt hypertensive animals, we examined the maximal vasodilator capacity of the contralateral kidney in 13 instrumented dogs during progression of Goldblatt hypertension. Constriction of a single renal artery (RAC) followed a week or more later by total renal artery occlusion (RAO) increased mean arterial blood pressure (BP) from a control level of 102 +/- 3 to 135 +/- 7 mmHg (P less than 0.001) and increased plasma renin activity (PRA) from 0.69 +/- 0.16 to 10.2 +/- 3.9 ng angiotensin I X ml-1 X h-1 (P less than 0.05) at 2 wk after RAO. The hypertension was accompanied by an increase in basal renal blood flow (RBF) from 224 +/- 21 to 300 +/- 27 ml/min (P less than 0.01) and RBF at maximal vasodilatation from 505 +/- 24 to 673 +/- 52 ml/min (P less than 0.05). Hypertension and the increase in PRA waned, but BP remained higher than control at 4 wk after RAO (117 +/- 6 mmHg, P less than 0.005). Basal and maximal RBF were sustained at the higher levels throughout the 4-wk period after RAO. When RBF was expressed on a per gram basis, basal and maximal flow before (3.72 +/- 0.40 and 8.26 +/- 0.62 ml X min-1 X g-1, respectively) did not differ from that in the final experiment after RAO (3.85 +/- 0.34 and 8.19 +/- 0.78 ml X min-1 X g-1). The basal and minimal vascular resistances based on flow per gram were increased by 24 +/- 8 and 41 +/- 16% (P less than 0.05), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)