Elevation of Collagenase Activity in Fatty Liver

Liver collagenase activity increased without liver cell necrosis in non-alcoholic and alcoholic fatty liver induced by feeding rats a choline-deficient diet or alcohol-liquid diet, respectively. The liver hydroxyproline content did not increase during a marked rise in collagenase activity in non-alcoholic fatty liver, but the content gradually increased after collagenase activity diminished. However, the hydroxyproline content increased slowly with a slight concomitant increase in collagenase activity in alcoholic fatty liver. The regulatory mechanism of fibrogenesis in fatty liver is discussed.