Hepatic collagenolytic cathepsin in patients with chronic liver disease.

Human hepatic collagenolytic cathepsin consisted of a major component having a molecular weight of 25 000 and a minor one of 35 000; the former is indistinguishable for cathepsin B in its enzymatic properties. Hepatic collagenolytic cathepsin increased in chronic active liver disease in proportion to hepatic hydroxyproline content. The ratio of collagenolytic cathepsin to hepatic hydroxyproline content remained within the normal range in chronic hepatitis, but decreased significantly in cirrhosis. These results suggest that collagenolytic cathepsin participates, at least partly, in the progress of hepatic fibrosis.