Distribution of γ-Glutamyl Transpeptidase in Male Reproductive System of Rats and its Age-Related Changes

Abstract
The present study is designed to investigate localization of gamma-glutamyl transpeptidase (gamma-GTP) in male reproductive organs and its age-related changes using Wistar rats aged 2 to 15 weeks. Histochemically, gamma-GTP activity was detected intensively in epithelial cells of epididymides and seminal vesicles and weakly in those of anterior prostates, but not in testes under the present conditions. Biochemically, the highest gamma-GTP activity was found in epididymal head portions. The order of the activity was epididymides (head greater than body greater than tail), seminal vesicles, prostates and testes. The activity increases with sexual maturation in epididymides and seminal vesicles, but not in prostates. Since gamma-GTP is an enzyme involved in the incorporation of amino acids, the present findings suggest that not only epididymides but also seminal vesicles possess uptake mechanisms for amino acids.