The role of the Ito cell in perivenular and intralobular fibrosis in alcoholic hepatitis.

The role of the Ito cells in perivenular and intralobular scarring in alcoholic liver disease was examined morphologically. There was a substantial decrease in the number of Ito cells in the midzone of the hepatic lobule in both fatty liver and alcoholic hepatitis as judged by light microscopy. By electron microscopy, however, an increase in "activated" Ito cells or a few fibroblasts were found in small foci of fibrosis in association with inflammation and hepatocellular degenerative changes in most cases of alcoholic hepatitis. Cytoplasmic protrusions of activated Ito cells extended to the hepatocytes undergoing degenerative changes including Mallory body formation. There was an apparent transition from Ito cells to activated Ito cells and to fibroblasts. It is suggested that Ito cells may play a role in perivenular and intralobular fibrosis in alcoholic hepatitis.