Materials and Methods

A method for the determination of serum arginase is given which combines the enzymatic formation of urea with the sensitive method of Coulombe (1) for meas-uring this substance. This procedure allows more accurate determinations in the normal range than do previous methods described and is convenient for clinical routine. Significant difference is found between the mean values of normal men and women, 3.9 units/L. for the former and 2.9 units/I. for the latter. A.RGINASE (L-arginine ureohydrolase E C 3.5.3.1) was described as early as 1904 by Kossel and Dakin (2). It is found in animals and plants, and has been identified in several human tissues: liver, breast, kidney, testes, salivary glands, epidermis, and erythrocytes. Liver is the main source. Arginase catalyzes the last reaction in the well-Imown urea cycle