EXPERIMENTAL INDUCTION OF MALLORY BODIES IN MICE BY GRISEOFULVIN TREATMENT

Abstract

Swiss albino mice were fed a diet containing 2.5 percent griseofulvin (GF) for 4 to 8 months in order to induce Mallory bodies (MBs) experimentally in the liver. Parts of the livers were obtained at various periods, and processed for light and electron microscopic studies. Light microscopic findings revealed that hepatocytes including clustered MBs were ballooned. It appeared the positive correlation between periods of GF feeding and increase in MBs. After 6 weeks' GF free period, MBs were still present, although much less in number. When GF diet was resumed, MBs increased rapidly. Electron microscopic findings revealed that MBs consisted of clustered fibrils with 150 A in diameter, which were arranged in a random manner and were not delineated by a membrane.
Among three subtypes of MBs classified by Yokoo et al, in our experimental model, Types II and III MBs were present but there was no Type I. Some of MBs were in contact with nuclear membrane, mitochondria and microsomes.
These results further support the hypothesis that MBs are related to intermediate filaments and GF induce increase of these filaments.