中文摘要：

目的探讨大鼠肝缺血再灌注（I／R）对胆小管纤维形肌动蛋白（F-actin）微丝的影响。方法采用肝缺血35min再灌注模型，检测血清中ALT、AST、GGT和TBIL的含量；电镜观察胆小管的变化；异硫氢胍荧光素标记的鬼笔环肽（FITC—Phalloidin）显示胆小管F—actin微丝的分布变化，激光共聚焦显微镜采集图像并定量分析。结果F-actin微丝荧光变化和电镜超微结构的改变相符合，F—actin的荧光染色再灌注前正常，而再灌注后明显减弱；胆小管微绒毛再灌注前没有消失，而再灌注后却大量脱落。这与血清GGT和TBIL的异常改变一致。结论再灌注而非缺血可造成胆小管F-actin微丝破坏、微绒毛丧失，导致胆小管收缩减弱，胆汁排泄功能受损。这可能是大鼠肝I／R后胆汁淤积发生的主要机制。

英文摘要：

Objective To investigate the effect of hepatic ischemia-reperfusion （I/R）on bile canalicular F-actin microfilaments in rat. Methods A model of rat hepatic ischemia-reperfusion was adopted and the ischemia time was 35 min. The levels of serum ALT, AST, GGT, and TBIL were measured. The changes of bile canaliculus were observed by transmission electron microscope. The modification of F-actin microfilaments was quantified by using FITC-Phalloidin and analyzed by confocal laser scanning microscopy imaging. Results This modification of F-actin staining was consistent with the observation by transmission electron microscopy. The staining of F-actin was normal in hepatocytes before reperfusion, but decreased significantly after reperfusion, and there was a marked loss of canalicular microvilli after reperfusion, which were in coincidence with abnormality of serum GGT and TBIL. Conclusion Reperfusion not ischemia induced disruption of F-actin microfilaments and a loss of microvilli, and these modifications could lead to impaired bile excretion by damaging canalicular contraction, which maybe the main mechanism of cholestasis after rat hepatic ischemia-reperfusion.