Objective:To study the effects of Gexia Zhuyu decoction on rat liver fibrosis

and examine its effects on the expression of matrix metalloproteinase-13 (MMP-13) and tissue inhibitors of metalloproteinase-1 (TIMP-1). Method: Rats were randomly divided into four groups as follows: blank control group

Gexia Zhuyu decoction group

porcine serum group

porcine serum plus Gexia Zhuyu decoction group. The fibrosis model of rats was achieved by intraperitoneal injection of porcine serum twice weekly for 12 weeks

simultaneously Gexia Zhuyu decoction was administered daily by gavage for 12 weeks. All rats were sacrificed at the end of experiment

and liver was collected for analysis. The liver histopathology was examined by Masson trichrome staining. The content of MMP-13 and TIMP-1 in the liver was detected by enzyme linked immunosorbent assay. Real-time reverse transcriptase polymerase chain reaction(Rt-PCR) was used to analyze MMP-13 and TIMP-1 mRNA levels in the liver. Result: Compared with the porcine serum group (10.38±2.01)%;MMP-13 protein(14.05±2.64)ng·g-1 liver;MMP-13 mRNA(1.91±0.73) folds;TIMP-1 protein(14.91±1.07)ng·g-1 liver;TIMP1 mRNA( 18.40±2.84) folds

the histopathology of rats given Gexia Zhuyu decoction improved significantly (6.66%±1.04%). The expressions of TIMP-1 mRNA and protein were decreased significantly:protein(13.47±1.22)ng·g-1 liver

and mRNA(4.89±0.74) folds

and MMP-13 mRNA and protein in liver were elevated significantly in porcine serum plus Gexia Zhuyu decoction group:protein(20.03±2.14)ng·g-1 liver; and mRNA(4.12±0.59) folds (P<0. 05). Conclusion: Gexia Zhuyu decoction may exert anti-hepatic fibrosis effect in rats via regulation of MMP-13 and TIMP-1 gene expression.