Effects of vasopressin and its deamino-D-arginine analogue on renin release in the isolated perfused rat kidney.

The direct action of arginine-vasopressin (AVP) and its deamino-D-arginine analogue (DDAVP) on renin release (RR) has been studied in isolated rat kidneys perfused with an electrolyte solution at constant pressure in a single-pass system. AVP and DDAVP infused at various concentrations (80 to 2100 pg/ml and 80 to 8700 pg/ml, respectively) reduced volume and increased osmolality of urine in a dose-dependent way. High doses of AVP reduced renal perfusate flow and glomerular filtration rate while DDAVP had no effect on renal haemodynamics. When vasoconstrictor doses of AVP or high concentrations of DDAVP were infused, "basal" RR remained unchanged. However, when RR had been stimulated by infusion of isoproterenol, vasoconstrictor doses of AVP as well as high doses of DDAVP which did not increase renal vascular resistance diminished RR by about 30% (P less than 0.01, and P less than 0.05, respectively). These results suggest that the inhibition of RR by vasopressin is not related to its vasoconstrictor action.