EFFECTS OF C-TYPE NATRIURETIC PEPTIDE ON RENAL VASOCONSTRICTION IN DOGS

Intrarenal arterial infusion of C-type natriuretic peptide (CNP, 50 ng /kg per min) increased urine flow rate without affecting glomerular fi ltration rate. Intrarenal arterial bolus injection of angiotensin II ( 25, 50 and 100 ng) or of norepinephrine (0.25, 0.5 and 1.0 mu g) reduc ed renal blood flow. The blood flow response induced by angiotensin II was slightly attenuated but the response induced by norepinephrine wa s unaffected during CNP infusion. These results suggest that exogenous CNP, even at the pharmacological dose that can induce diuresis, has l ittle effect on the canine renal vasculature. (C) 1997 Elsevier Scienc e B.V.