DISTRIBUTION OF ALPHA-FETOPROTEIN-CONTAINING AND ALBUMIN-CONTAINING CELLS IN LIVERS OF FISCHER RATS FED 4 CYCLES OF N-2-FLUORENYLACETAMIDE

Abstract

Immunofluorescent localization of .alpha.-fetoprotein (AFP)-and albumin-containing cells was determined in the livers of Fischer rats fed 0.05% N-2-acetylfluorenamide for four 2-wk-on, 1-wk-off cycles. After this exposure multiple changes in the liver include over 1000 neoplastic nodules/liver, as well as extensive production of so-called oval cells and focal zones of atypical hepatocellular hyperplasia. Approximately 1% of the oval cells contain AFP, and about half of the zones of atypical hyperplasia include cells that contain AFP, but none of the neoplastic nodules or normal hepatocytes have any AFP-containing cells. Since up to 60% of the hepatocellular carcinomas developing from this regimen will predictably produce AFP, hepatocellular carcinoma may arise not only from premalignant neoplastic nodules but also from oval cells or the atypical differentiation of hepatocytes.