Aim: To evaluate the effect of chronic thrombin inhibition by heparin on experimentally induced chronic liver injury (liver fibrosis) in rats.
Methods: Chronic liver injury (liver fibrosis) was induced in Wistar rats by oral administration of carbon tetrachloride (CCl4) for 7 wk, an animal model with persistent severe hepatic fibrosis. Intravenous administration of the thrombin antagonist (heparin) started 1 wk after the start of CCl4 intoxication for 6 wk. After completion of treatment (7 wk), markers of hepatic dysfunction were measured and changes evaluated histopathologically.
Results: Higher serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), alkaline phosphatase (ALP), total, direct and indirect bilirubin levels, as well as lower fibrinogen levels, were found in CCl4 intoxicated rats. Heparin, silymarin and combination of drug (heparin and silymarin) treatment for 6 wk prevented a rise in SGOT, SGPT, ALP, total, direct and indirect bilirubin levels and improved fibrinogen levels. Deterioration in hepatic function determined by the fibrosis area was retarded, as evident from hepatic histopathology. Total protein levels were not changed in all groups.
Conclusion: Heparin, a thrombin antagonist, preserved hepatic function and reduced severity of hepatic dysfunction/fibrogenesis. Combination of heparin and silymarin produced additional benefits on liver fibrosis.
Keywords: Carbon tetrachloride; Heparin; Hepatic dysfunction; Liver fibrosis; Thrombin antagonist.