Expression of matrix metalloproteinases and tissue inhibitors of metalloproteinase in rats with cavernous transformation of portal vein and their role in peripheral angiogenesis / 中国组织工程研究

ABSTRACT

BACKGROUND:At present, there is no effective treatment strategy for cavernous transformation of portal vein and basic research about its etiology is rarely reported. OBJECTIVE:To establish the models of cavernous transformation of portal vein, detect the expression of matrix metal oproteinase-2,-9 (MMP-2, MMP-9) and tissue inhibitors 1, 2 of metal oproteinase (TIMP-1, TIMP-2) in rat portal vein and peripheral tissue, and discuss the roles in the process of peripheral angiogenesis. METHODS:Eighty Sprague-Dawley rats were randomly divided into three groups. The rat models of cavernous transformation of portal vein were established with partial coarctation in portal vein by using 21 G blunt pinhead. Control group was normal rats without operation (samples were harvested after portal vein radiography). Model group and sham operation group were divided into three groups respectively according to different time points, namely 2, 4 and 6 weeks after operation. Rats of each group were randomly chosen at week 2, 4 and 6 after operation to observe the formation of col ateral circulation of portal vein and its peripheral tissues by performing portal vein radiography. CD31 was detected by immunohistochemistry. The expression of MMP-2, MMP-9, TIMP-1, TIMP-2 mRNA and protein in portal vein and peripheral tissue were determined by RT-PCR and immunohistochemistry respectively. RESULTS AND CONCLUSION:Peripheral angiogenesis of model group was increased obviously by portal vein radiography and immunohistochemistry. RT-PCR and immunohistochemistry results demonstrated that, compared with the control group and sham operation group, the expression of MMP-2 mRNA and protein in model group were significantly increased at weeks 2, 4, and 6 (P0.05). Ratio of MMP-2/TIMP-2 of model group was significantly higher than that of control group and sham operation group (P<0.05) at week 2. the rat models of cavernous transformation of portal vein have low mortality, high success rate and are stable. Upregulation of the expression of MMP-2, MMP-9 and the disbanlance of the ratio of MMP-2/TIMP-2 might contribute to the peripheral angiogenesis in rats with cavernous transformation of portal vein.