title: Detection of gamma glutamyl transpeptidase in the livers of germfree and conventional rats.
abstract: Germfree and conventional rats, 1-41 months of age, were examined for gamma glutamyl transpeptidase in frozen sections prepared from their livers. This histochemical marker has been associated with early changes which develop following exposure to known carcinogenic agents. Positive gamma glutamyl transpeptidase markers were detected in 86% of germfree rats over 4 months of age, and the gamma glutamyl transpeptidase foci were larger and more numerous as the animals aged, and the foci were prominent in rats with hepatic tumors. Gamma glutamyl transpeptidase foci were observed in 96% of livers from conventional rats at 11-20 months of age. The agents responsible for induction of the gamma glutamyl transpeptidase foci in the liver were not identified.
mesh_terms: D000375:Aging; D000818:Animals; D005260:Female; D005856:Germ-Free Life; D008099:Liver / Q000201:enzymology*; D008113:Liver Neoplasms / Q000175:diagnosis / Q000201:enzymology / Q000662:veterinary*; D008297:Male; D051381:Rats / Q000378:metabolism*; D011919:Rats, Inbred Strains / Q000378:metabolism; D005723:gamma-Glutamyltransferase / Q000032:analysis*
chemical_list: D005723:gamma-Glutamyltransferase