SERUM COLLAGENASE ACTIVITY IN CHRONIC LIVER-DISEASES

To examine whether serum collagenase activity reflects the amount of h epatic collagenase in the fibrotic liver, we measured serum collagenas e activity in 67 patients with chronic liver disease and in 26 healthy controls. Collagenase activity in serum was measured after reactivati on by denaturing and dissociating the inhibitors with 3 M KSCN and 1 m M aminophenylmercuric acetate. Serum collagenase activity was 35% lowe r than control in chronic persistent hepatitis, 48% lower in chronic a ctive hepatitis, 56% lower in fiver cirrhosis and 68% lower in hepatoc ellular carcinoma. To interpret this finding of low serum collagenase activity we measured serum concentration of TIMP (Tissue Inhibitor of Metallo-Proteinases). Serum TIMP concentration was increased as liver disease developed, and it was inversely correlated with serum collagen ase activity. These results suggest that in this assay condition serum collagenase activity is influenced by TIMP, and thus may not reflect the amount of hepatic collagenase in patients with chronic fiver disea se.