Abstract: | The effects of a synthetic alpha-human atrial natriuretic polypeptide (alpha-hANP) on renal hemodynamics and urine formation were investigated in anesthetized dogs. Intrarenal arterial infusion of the peptide (1.0 microgram/min) increased renal blood flow, glomerular filtration rate and urine flow with no change in systemic blood pressure. A lower dose of alpha-hANP (0.2 micrograms/min) produced a significant diuresis and natriuresis, while renal hemodynamics remained unchanged. The urinary excretion of Na, Cl and Ca was increased in proportion to the urine flow. We propose that alpha-hANP inhibits tubular reabsorption of electrolytes, and in higher dose produces renal vasodilation. |