Vasopressin and renin in glycerol-induced acute renal failure in the rat.

Acute renal failure was induced in dehydrated rats by intramuscular injection of glycerol (50%, 10 ml/ kg). The total period of observation after glycerol injection was 8 hours. Hematocrit and plasma osmolality increased transiently and reached maximum values between 1 and 2 hours; plasma urea concentration rose progressively during the 8-hour period. Plasma levels of arginine-vasopressin had increased 40-fold by 2 hours after glycerol injection, whereas plasma renin concentrations were only 2-3 times higher than in controls. Plasma renin substrate concentrations had doubled by 8 hours. In rats with acute renal failure, blood pressure was higher than in controls injected with saline. Injection of vasopressin antiserum lowered blood pressure by 10 ± 2 (SE) mm Hg, while a competitive antagonist of angiotensin II, saralasin, had no effect. It is concluded that after glycerol injection the increased plasma concentrations of vasopressin induced systemic vasoconslriction. The renin-angiotensin system does not significantly contribute to the rise in systemic vascular resistance.