Cytoskeletal alterations leading to Mallory body formation in livers of mice fed 3,5-diethoxycarbonyl-1,4-dihydrocollidine.

Cytoskeletal alterations of hepatocytes were studied in mice fed 3,5-diethoxycarbonyl-1,4-dihydrocollidine from the onset of the experiment to the time when Mallory bodies were induced, using immunofluorescent microscopy and a method which we devised in order to visualize the cytoskeletal framework of hepatocytes. The results showed that the cytoskeletal framework of the normal murine hepatocyte is composed of a network of uniformly distributed, interconnecting bundles of filaments. In the drug-fed mice, the cytoskeletal network of the hepatocytes became coarser and distorted. The Mallory body-containing hepatocytes were mostly devoid of cytoskeletal filaments, containing only a few thick bundles of filaments, which appeared partly smudgy and electron-dense. These results suggest that the formation of Mallory bodies in this animal model is associated with a marked derangement of the cytoskeletal framework, which appears to result from the progressive loss of normal filaments and the aggregation of abnormal ones.