STUDIES ON ACTION AND INTERACTION OF DOPAMINE AND PROSTAGLANDIN-A1 IN RENAL VASCULATURE

Abstract

Dopamine (3 .mu.g/kg per min) and prostaglandin A1 (PGA1, 0.2 .mu.g/kg per min) dilated the renal vasculature and increase total kidney blood flow in the anesthetized dog. These effects of dopamine, but not of PGA1, were completely antagonized by bulbocapnine, a selective dopamine receptor inhibitor, at a dose (3 mg/kg) which did not itself significantly alter cardiovascular hemodynamics. Indomethacin, an inhibitor of PG synthetase in the dog at 2 mg/kg, did not reduce the dopamine renal vascular response. Dopamine and PGA1 may decrease renal vascular resistance in the dog via distinct pharmacological mechanisms.