Hepatic inactivation of renin.

Renin activities were measured in plasma from an artery and from the hepatic, portal, and renal veins of anesthetized dogs. A significant arterialhepatic venous renin difference was observed during control periods and after elevation of arterial renin by stimulation of endogenous renin secretion (induced by acute salt depletion) or by infusion of exogenous renin. There was good quantitative agreement between the calculated rates of renin infusion and hepatic renin clearance. No significant arterial-portal venous renin difference was observed. Infusion of exogenous renin decreased the usual renal venous-arterial renin difference; slight net renal inactivation of renin was observed in only 2 of 12 periods. We conclude that the liver is the major site of renin inactivation. ADDITIONAL