摘要AIM: To investigate the location and expression of TIMP-1 and TIMP-2 in the liver of normal and experimental hepatic fibrosis in rats.METHODS: The rat models of experimental immunity hepatic fibrosis (n=20) were prepared by the means of immunologic attacking with human serum albumin (HSA),and normal rats (n=10) served as control group. Both immunohistochemistry and in situ hybridization methods were respectively used to detect the TIMP-1 and TIMP-2 mRNA and related antigens in liver. The liver tissue was detected to find out the gene expression of TIMP-1 and TIMP-2 with RT-PCR.RESULTS: The TIMP-1 and TIMP-2 related antigens in livers of experimental group were expressed in myofibroblasts and fibroblasts (TIMP-1: 482±65 vs60±20; TIMP-2:336±48 vs 50±19, P＜0.001). This was the most obvious in portal area and fibrous septum. The positive signals were located in cytoplasm, not in nucleus. Such distribution and location were confirmed bysitu hybridization (TIMP-1/β-actin: 1.86±0.47 vs 0.36±0.08; TIMP-2/ β-actin: 1.06±0.22 vs 0.36±0.08,P＜0.001). The expression of TIMP-1 and TIMP-2 was seen in the liver of normal rats, but the expression level was very low. However, the expression of TIMP-1 and TIMP-2 in the liver of experimental group was obviously high.CONCLUSION: In the process of hepatic fibrosis, fibroblasts and myofibroblasts are the major cells that express TIMPs.The more serious the hepatic fibrosis is in the injured liver,the higher the level of TIMP-1 and TIMP-2 gene expression.