Effect of Diets and Hormones on Two Urea Cycle Enzymes.

Abstract

All treatments increasing protein catabolism produced an increase in arginine synthetase activity in rats. Arginase activity increased only when the increased protein breakdown was accompanied by an increase in or maintenance of body weight. Changes in lactic acid dehydrogenase, used as a control enzyme, more nearly parallelled those in arginase and showed very little relationship to changes in arginine synthetase. It is suggested that arginine synthetase would be a better indicator enzyme of nitrogen catabolism than arginase.