Abstract: AIM: To further explor and study the mechanism of γ-interferon in treating hepatic fibrosis on the basis of clinical practice of treatment for hepatic fibrosis. METHODS: 17 male Wistar rats were divided into three groups.The rat fibrosis model was induced by pig serum except for normal control group.The other two groups were both given intraperitoneal injection of pig serum respectively (0.5 ml once, 2 times per week, total 12 weeks).In γ-interferon treated group, the rats were subcutaneous injected γ-interferon one hundred thousand IU every day at the ninth week.The model group and normal control group were fed with the same amount of saline by gavage.The rats were killed at the end of the twelfth weeks, the pathology of liver fibrosis was observed with HE stain and Masson stain.Collagen I mRNA and collagen III mRNA were detected in liver samples with RT-PCR, immunohistochemistry was used to observe the expression of collagen I, III protein.RESULTS: Upon pathological examination, the γ-interferon treatment had significantly reversed pig serum-induced liver fibrosis.In γ-interferon treatment group, the γ-interferon could enhance the degradation of collagen in the rat fibrotic liver according to HE and Masson staining compared with the fibrotic model group(P<0.05).Moreover, in γ-interferon treatment group, the expression of collagen I, III and its protein in liver were markedly reduced, respectively according to RT-PCR analysis and immunohistochemistry as compared with model group.CONCLUSION: The rat hepatic fibrosis induced by pig serum can be obviously reversed by γ-interferon.The mechanism of treating hepatic fibrosis with γ-interferon appears to be due to the enhancement of the degradation of collagen in liver, at last resulted in hepatic fibrosis been reversed eventually.

Key words: hepatic fibrosis, collagen I,III, γ-interferon, liver, rats