Urinary output modulation of alanine aminopeptidase, gamma-glutamyl transpeptidase and N-acetyl-beta-D-glucosaminidase by castration and testosterone in male normal rat.

The urinary excretion of alanine aminopeptidase (AAP), gamma-glutamyl transpeptidase (gamma-GT) and of N-acetyl-beta-D-glucosaminidase (NAG) was studies in normal and castrated rats receiving either testosterone for 5 post-operative weeks or no hormone. In castrated rats the urinary output of AAP and gamma-GT was significantly lower than in sham control or in castrated rats receiving testosterone. In addition, an excess of exogenously given testosterone had no effect on enzymuria of normal rats. The urinary excretion of NAG was influenced neither by castration nor by testosterone. These results suggest that endogenous testosterone is responsible for a permanent positive control on the urinary excretion of AAP and gamma-GT.