Rate of Disappearance of Exogenous Dog Renin from the Plasma of Nephrectomized Dogs

Abstract

Summary Exogenous dog renin was administered intravenously to nephrectomized dogs and its disappearance followed for 3 hours. There were two exponential components to the disappearance curves, a rapid component with an average half-time of 6 ± 1 min and a slower component with an average half-time of 79 ± 7 min. Circulating angiotensin levels were shown to have no effect on either half-time value and the presence of adequate substrate was demonstrated. The mean plasma renin level in pentobarbital-anesthetized dogs was found to be 10.2 ± 1.0 mμg angiotensin II generated/ml/3 hours. Four hours after nephrectomy, it was 1.3 ± 0.2 mμg. This suggests that the half-time of endogenous renin is similar to that of exogenous renin.