【摘要】 目的探讨鼠肝缺血再灌注后血浆胆红素升高发生的分子机制。方法实验分为假手术组(A 组),70%的鼠肝缺血35 min 再灌注组(B 组),研究时点为再灌注后的1 h、6 h、1 d、3 d、5 d。HE 染色分析肝组织病理改变。计算胆汁生成率,常规生化方法检测胆汁、血浆中胆红素含量的变化。荧光定量 PCR 检测肝组织多耐药相关蛋白2(MRP2)以及肝细胞骨架连接蛋白根蛋白的表达。激光共聚焦方法分析 MRP2、根蛋白在肝细胞毛细胆管膜上的定位。结果 70%鼠肝缺血35min 再灌注模型炎症反应轻,无肝细胞坏死的发生。与 A 组比较,B 组再灌注后的1 h～3 d,胆汁生成率及胆汁中结合胆红素含量明显降低;再灌注后的1 h～5 d,血浆中胆红素含量显著增加。荧光定量聚合酶链反应(PCR)发现,再灌注后6 h～5 d,B 组根蛋白表达下调,以再灌注后的6 h～1 d 尤为明显,MRP2表达的明显下调仅发生在再灌注后的6 h。激光共聚焦分析发现,再灌注后的6 h～5 d 在根蛋白表达缺失处,B 组 MRP2在毛细胆管膜上的定位减少。结论根蛋白表达下调所致的 MRP2在毛细胆管膜上的定位减少很可能是鼠肝缺血再灌注后血浆胆红素升高发生的分子机制。更多还原

【Abstract】 Objective To investigate the mechanism of increase of serum bilirubin after hepatic ischemia-reperfusion.Methods 104 SD rats were randomly divided into 2 groups:Group A(sham operation group)and Group B(undergoing 70% hepatic 35min ischemia-reperfusion).Then the rats were subdivided into subgroups according the different time points(1 and 6 hours,and 1,3,5 days after reperfusion).Bile of the ischemic hepatic lobes and blood from the vena eava were collected to examine the conjugated bilirubin(CB)in the bile and serum,and total bilirubin(TB)and alanine aminotransferase (ALT)in serum,and the bile generation rate was calculated.Tissues of the left liver lobe were collected to undergo microscopy with hematoxilin and eosin staining.Real time fluorescence PCR was used to analyze the mRNA expression of multi-drug resistance-associated protein 2(MRP2)and radixin,a cytoskeleton crossslinker protein.Laser confocal method was used to analyze the localization of MRP2 and radixin in canalicular membrane.Results Pathological examination showed that there was only a mild inflammation in the liver tissues that had undergone ischemia-reperfusion,and no necrosis of hepatocytes was seen.1 h～3 d after reperfusion,the bile generation rate and CB level in bile were significant decreased,and the serum TB and CB levels were significantly increased 1 h～5 d after reperfusion.Radixin expression was significantly reduced 6 h～1 d after reperfusion,but down-regulation of MRP2 only occurred 6 h after reperfusion, Localization of MRP2 in the canalicular membrane was absent when the expression of radixin was missing. Conclusion Absence of MRP2 localization in canalicular membrane resulted from missing of radixin expression may be the mechanism of an increase of serum bilirubin after hepatic ischemia-reperfusion.更多还原