Gamma glutamyl transpeptidase activity in rat urothelium treated with bladder carcinogens

Gamma glutamyl transpeptidase (GGT) activity during urothelial carcinogenesis was examined histochemically in rats treated with N-methyl-N-nitrosourea (MNU) or N-butyl-N-(4-hydroxybutyl)nitrosamine (BHBN). GGT-positive cells developed with a high frequency in foci of nodulopapillary hyperplasia and carcinoma. GGT-positive cells, both individually and in nests, were also frequent in foci of simple hyperplasia and interlesion normal urothelium of carcinogen-treated bladders. The results suggest that development of GGT-positive cells in interlesion normal urothelium is specific to carcinogen treatment.