Effect of Vasoactive Agents on the Distribution of Renal Cortical Blood Flow in Dogs

Abstract

The distribution of renal cortical blood flow was studied in 6 Nembutal anesthetized dogs during control periods and during infusions of adrenaline, noradrenaline, angiotensin and vasopressin. Local cortical blood flow was measured as H2 gas desaturation rate recorded polarographically by platinum electrodes in outer and inner cortex. The total renal blood flow (RBF) was measured by an electromagnetic flow meter. In the control period the outer cortical blood flow (OCF) and inner cortical blood flow (ICF) averaged 3.59 (+/- S.D. 0.85) ml/min - g and 3.23 (+/- S.D. 0.64) ml/min - g, respectively. Infusions of the various vasoactive agents caused essentially equal vascular responses. All agents caused increased local renal resistance and reduction of RBF whether given intravenously or intraarterially. The RBF could be lowered to 20-50% of initial control flow by increasing doses of vasoactive agents. OCF and ICF fell proportionately and almost to the same extent as RBF, or OCF fell slightly more than ICF. There was no evidence for patchy or zonal hypoperfusion in cortex caused by infusion of adrenaline, noradrenaline, angiotensin and vasopressin.