Abstract
Chymase, a protease of human mast cells, promotes myocardial and renal interstitial fibrosis by converting angiotensin I to angiotensin II. We established a method for measuring chymase in liver tissue and examined the relationship between chymase and fibrosis in livers of patients with chronic hepatitis or autoimmune disease. We found that chymase levels were higher in livers from patients with chronic hepatitis and more severe fibrosis and were higher in livers from patients with autoimmune disease than in livers from patients with acute hepatitis. When sections of livers from patients with chronic hepatitis or autoimmune disease were immunostained for chymase, immunoreactive mast cells were detected in portal areas and sinusoidal walls, coinciding with the zone of fibrosis. Thus, chymase appears to be involved in hepatic fibrosis in chronic liver diseases.
