基质金属蛋白酶及其抑制剂在肝纤维化中的表达变化

目的 观察肝纤维化形成过程中基质金属蛋白酶MMP-1及其抑制剂TIMP-1的表达变化,从细胞外基质降解代谢的角度研究四氯化碳(CCl4)中毒性肝纤维化发生的机制.方法 雄性Wistar大鼠20只,分为正常组和肝纤维化模型组.肝纤维化组采用CCl4、饮酒、高脂低蛋白饮食等复合病因刺激制备肝纤维化动物模型,造模时间为8周.实验结束后测定肝脏指数、血清透明质酸(HA)、谷丙转氨酶(ALT)及尿羟脯氨酸(HYP)排出量,光镜下观察肝组织纤维化程度,并用免疫组化SABC法检测肝组织中Ⅰ、Ⅲ型胶原蛋白及MMP-1、TIMP-1的表达,同时用荧光实时定量PCR(RT-PCR)的方法检测肝组织中MMP-1、TIMP-1 mRNA的表达.结果 与正常对照组比较,肝纤维化模型组大鼠肝脏指数、血清HA及ALT显著增高,尿羟脯氨酸的排出量明显增加,病理组织学检查发现肝组织内纤维结缔组织增生明显,有假小叶形成；免疫组化的结果显示肝组织内Ⅰ、Ⅲ型胶原蛋白、MMP-1及TIMP-1的表达较正常组显著增加.结论 肝组织中MMP-1及TIMP-1的表达变化可能是导致肝纤维化的重要机制之一.

Changes in expression of MMP-1 and its inhibitor TIMP-1 in rat hepatic fibrosis

Objective To investigate the expression of MMP-1 and TIMP-1 in rat hepatic fibrosis and explore its possible mechanism in hepatic fibrosis. Methods Twenty male Wistar rats were randomly divided into the normal control group and the CC14-induced hepatic fibrosis group. The rat hepatic fibrotic models were induced by subcutaneous injection of CC14, drinking alcohol, and diet of hyperliposis and hypoprorein for 8 weeks. At the end of the experiment, we calculated the level of liver index, serumal hyaluronic acid （HA）, alanine aminotransferase （ALT） and the urinary excretion of hydroxyproline （HYP）. We de- tected the expression of COL Ⅰ, and Ⅲ, MMP-1 and TIMP-1 by immunohistochemical techniques and Realtime PCR. Results Comparing ai[ the indexes of the two groups, the liver index, levels of serumal HA and ALT, the urinary excretion of HYP were all significantly increased in hepatic fibrosis. The expression of COL I and III,MMP-1 and TIMP-1 in liver tissues was also elevated. Conclusion Changes in the expression of MMP-1 and TIMP-1 in the liver tissues may play an important role in hepatic fibrosis.