PTEN在肝纤维化大鼠肝组织中的动态表达

目的： 探讨大鼠肝纤维化过程中肝组织PTEN的动态表达。方法: 采用胆总管结扎法建立大鼠肝纤维化模型，HE及Masson三色染色检测肝脏组织学变化，免疫组织化学染色、Western blotting及实时荧光定量PCR技术检测大鼠肝组织的PTEN蛋白及mRNA表达。结果: 大鼠肝纤维化模型成功建立，随着造模时间延长，肝纤维化程度逐渐加重，造模不同时间均可见不同程度的肝细胞变性坏死而导致正常肝细胞逐渐减少；免疫组织化学染色显示正常大鼠肝组织中PTEN广泛表达，主要表达于细胞浆，随着肝纤维化的进展，PTEN阳性表达细胞逐渐减少（P<0.01）；Western blotting及实时荧光定量PCR显示造模1周、2周、3周及4周不同时间大鼠纤维化肝组织中PTEN蛋白及mRNA表达均显著低于假手术组（P<0.01），并随着肝纤维化的进展逐渐降低（P<0.01）。结论: 大鼠纤维化肝组织中PTEN蛋白及mRNA表达均随着肝纤维化的进展逐渐降低，其下降程度与肝纤维化程度一致。

Dynamic expression of PTEN in liver tissue of rats with hepatic fibrosis

AIM: To investigate the dynamic expression of phosphatase and tensin homolog deleted on chromosome ten (PTEN) in liver tissue in the process of hepatic fibrosis in rats. METHODS: The rat model of hepatic fibrosis used in this study was induced by common bile duct ligation (BDL). Hematoxylin and eosin (HE) and Masson’s trichrome staining were used for observing the histological changes in hepatic fibrosis tissue. At 4 time points, the expressions of PTEN protein and mRNA in hepatic tissues of rats were detected by immunohistochemical staining, Western blotting and real-time fluorescent quantitative PCR assay, respectively. RESULTS: The rat model of hepatic fibrosis was established successfully. With each consecutive week after BDL, increased fibrosis, degeneration and necrosis were found in rat liver cells. Not surprisingly, a disruption of normal architecture and a decrease in normal hepatic cells was concomitantly observed. The immunohistochemical staining indicated that there was extensive expression of PTEN in liver tissues of normal rats, it expressed mainly in the cytoplasm, and with the aggravation of hepatic fibrosis, the expression of PTEN in liver tissues decreased gradually (P<0.01). Western blotting and real-time fluorescent quantitative PCR at weekly time points (1, 2, 3, and 4 weeks) after BDL showed that, the expression of PTEN protein and mRNA in fibrotic rat liver tissue decreased gradually with increasing severity of hepatic fibrosis (P<0.01). Furthermore, all values from BDL rats were significantly lower than those from the sham operation group (P<0.01). CONCLUSION: The expressions of PTEN protein and mRNA in fibrotic liver tissue of rat decrease gradually with the progression of hepatic fibrosis, and increasing severity of fibrosis correlated well with decreasing PTEN expression.