GENESIS OF UNUSUAL VESICLES IN RAT PERIPORTAL HEPATOCYTES AFTER ADMINISTRATION OF N-HYDROXY-2-ACETYLAMINOFLUORENE

Administration of N-hydroxy-2-acetylaminofluorene (90 ώmol/kg, iv) to rats results in damage to periportal hepatocytes. The most prominent ultrastructural changes are the appearance of numerous unusual vesicles of about 200 nm diameter and the proliferation of the endoplasmic reticulum to form fingerprint-like structures. In order to characterize these vesicles and to investigate their possible origin, their enzymatic activity was studied by ultrastructural enzyme histochemistry.