ARGININE-VASOPRESSIN DISPOSITION IN THE CONSCIOUS RABBIT

To characterize the urinary kinetics of AVP, and the influence of regi onal blood dow on the metabolic degradation of AVP, multiple doses of AVP were administered to conscious rabbits. AVP systemic clearance (Cl -T) was not influenced by changes in dose, in spite of a decrease in A VP urinary clearance following the highest dose. Hepatic blood dow was inversely associated with AVP concentrations, and despite a decrease in hepatic plasma flow of 37% (p < 0.05), following the high dose of A VP, Cl-T remained unchanged. These results indicate that AVP plasma ki netics are first order and plasma flow independent, and urinary kineti cs are zero order.