SPONTANEOUS OCCURRENCE OF GAMMA-GLUTAMYL-TRANSFERASE TRANSPEPTIDASE-POSITIVE HEPATOCYTIC FOCI IN 105-WEEK-OLD WISTAR AND 72-WEEK-OLD FISCHER 344 MALE-RATS

  • 1 January 1981
    • journal article
    • research article
    • Vol. 67  (2) , 407-412
Abstract
Spontaneous hepatic changes in old male rats of Wistar and F344 inbred strains were studied histochemically. .gamma.-Glutamyl transpeptidase-positive hepatocytic foci and cholangiolar proliferation associated with fibrosis and inflammatory infiltration were common findings in the old rats of both strains. Histochemical properties of the hepatocytes of the foci were similar to those of hyperplastic foci seen in early stages of liver carcinogenesis due to various chemical carcinogens. The incidence of the foci was 2.52/cm2 of the histochemically stained sections in 105-wk-old male Wistar rats and 1.60/cm2 in 72-wk-old male F344 rats. Altered hepatocytic foci significantly increased after 18 mo. of age in Wistar and F344 rats and the presence of other spontaneous neoplastic and non-neoplastic changes was revealed.