title: Distribution of gamma-glutamyl transpeptidase in the mouse epididymis and its response to acivicin.
abstract: gamma-Glutamyl transpeptidase (gamma-GT), its substrate (GSH) and hydrolytic product (L-glutamic acid) were measured biochemically in mouse reproductive tissues. The epididymal caput and seminal vesicles showed the highest specific activities of gamma-GT, while GSH and L-glutamic acid were widely distributed in all tissues. Histochemically, gamma-GT displayed a strong apical and supranuclear reaction and a moderate basal activity in the ductuli efferents, a weak luminal reaction in the first, a moderate apical reaction in the second and a strong apical and supranuclear reaction in the third segment of the epididymal caput. In the epididymal corpus and cauda, the gamma-GT reaction was confined to the tubular lumina but an apical reaction was also present in the cauda. The daily administration of acivicin (12 mg/kg body weight), an irreversible inhibitor of gamma-GT, for 14 days resulted in a 60% suppression of the enzyme activity in the epididymal caput, while the gamma-GT inhibition in the kidney was greater than 95%. The treatment caused no change in the activity of alanyl aminopeptidase. Histochemically, the basal and supranuclear gamma-GT activities in the ductuli efferents and the third epididymal segment were suppressed, but the apical reactions were maintained. The in-vivo suppression of epididymal gamma-GT activity may have implications in the control of post-testicular sperm maturation.
authors.affiliation: Department of Anatomy, University of Kuopio, Finland.
authors.forename: Y P
authors.initials: YP
authors.lastname: Agrawal
authors.forename: T
authors.initials: T
authors.lastname: Peura
authors.forename: T
authors.initials: T
authors.lastname: Vanha-Perttula
mesh_terms: D000818:Animals; D004822:Epididymis / Q000187:drug effects / Q000201:enzymology*; D005971:Glutamates / Q000378:metabolism; D018698:Glutamic Acid; D005978:Glutathione / Q000378:metabolism; D007555:Isoxazoles / Q000494:pharmacology; D007668:Kidney / Q000187:drug effects; D008297:Male; D051379:Mice; D012669:Seminal Vesicles / Q000201:enzymology; D005723:gamma-Glutamyltransferase / Q000378:metabolism*
chemical_list: D005971:Glutamates; D007555:Isoxazoles; D018698:Glutamic Acid; D005723:gamma-Glutamyltransferase; D005978:Glutathione; C006303:acivicin