【摘要】 目的　在大鼠实验性肝癌发生过程中原位显示端粒酶及其变化。方法　用含 0 .0 5 % 3′ 甲基 4 二甲基氨基偶氮苯的玉米粉喂饲大鼠 12周以制备肝癌模型。组织冰冻切片酶催化端粒延伸 PCR(原位TRAP)法检测端粒酶活性。结果　正常肝细胞、胆管细胞以及汇管区细胞一般均阴性。肝纤维化、早期肝硬化病变中一小部分肝细胞呈弱阳性 ,间质内增生的肌纤维母细胞端粒酶活性较强 ,增生的胆管细胞和结节状增生肝细胞显示弱至中等强度酶活性。不典型增生的胆管细胞及肝细胞内可见较强的酶活性。肝细胞性肝癌和胆管细胞性肝癌中绝大部分癌细胞可见端粒酶表达 ,但强弱不一。上述端粒酶活性一般位于细胞核内。结论　大鼠肝癌发生过程中端粒酶活性逐渐增加提示该酶对肿瘤细胞获得永生化特性具有重要意义。更多还原

【Abstract】 Purpose Investigating the in situ expression and change of the rat liver telomerase under experimental carcinogenesis. Methods The liver carcinogenesis model was made by feeding rats with 0.05% 3′?methyl dimethylazobenzene(DAB) in maize powder for 12 weeks.The detection of telomerase activity was performed using in situ telomeric repeat amplification protocol(in situ TRAP)assay on frozen section. Results The normal hepatocytes,bile duct cells and cells in the portal area were telomerase negative.A small part of hepatocytes in the fibrotic and cirrhotic liver had weak telomerase activity,while the proliferating myofibroblasts in the stroma showed stronger activity.Mild to moderate telomerase activity was detected in the proliferation bile ducts and hepatocytes.Stronger telomerase activity was seen in dysplastic cholangiocytes and hepatocytes.Telomerase expressed in most of the cancer cells in hepatocellular carcinoma and cholangiocarcinoma.Discrepancy in expression degree existed among individual cancer cells.Telomerase activity was generally located in the cell nuclei. Results The normal hepatocytes,bile duct cells and cells in the portal area were telomerase negative.A small part of hepatocytes in the fibrotic and cirrhotic liver had weak telomerase activity,while the proliferating myofibroblasts in the stroma showed stronger activity.Mild to moderate telomerase activity was detected in the proliferation bile ducts and hepatocytes.Stronger telomerase activity was seen in dysplastic cholangiocytes and hepatocytes.Telomerase expressed in most of the cancer cells in hepatocellular carcinoma and cholangiocarcinoma.Discrepancy in expression degree existed among individual cancer cells.Telomerase activity was generally located in the cell nuclei. Conclusions Gradual increasing of the telomerase activity in the liver carcinogenesis implys that telomerase activation is an important event in the immortal cell formation during the process.更多还原