肝动脉复流时机对大鼠肝内胆管上皮细胞缺血再灌注后超微结构的影响

Effect of the timing of hepatic artery reperfusion on ultrastructure of intrahepatic bile duct epithelialcells in rats after ischemia reperfusion

目的观察不同肝动脉复流时机对大鼠肝内胆管上皮细胞缺血再灌注损伤后超微结构的影响。方法建立大鼠原位部分肝脏缺血再灌注损伤模型,54只大鼠随机分为假手术组(SO)、肝动脉先复流组(IAR)和门静脉先复流组(IPR),IAR组、IPR组分别于复流后0．5、2．0、4．0、12．0h时取材,用透射电镜观察肝内胆管上皮细胞的超微结构,通过计算机图像分析系统对线粒体形态计量分析。结果(1)随着缺血再灌注后时间的延长,IAR组与IPR组肝内胆管上皮细胞损伤均有加重趋势,表现为线粒体肿胀、嵴模糊或消失、微绒毛减少等超微结构改变。(2)IPR 0．5 h组、IPR 2 h组胆管上皮细胞与IAR组相应时间点比较,超微结构损害无明显加重,线粒体平均面积、平均周径及数密度差异均无统计学意义(P＞0．05)；但IPR 4 h组、IPR 12 h组与IAR组相应时同点比较,超微结构损害加重,线粒体平均面积增大,差异有统计学意义(P＜0．05),线粒体平均周径增大,差异有统计学意义(P＜0．05),其中IPR 12 h组线粒体数密度减少,差异有统计学意义(P＜0．05)。结论与门静脉先复流相比较,肝动脉先复流对大鼠肝内胆管上皮细胞缺血再灌注后的超微结构具有保护作用。

Objective To observe the effect of the timing of hepatic artery reperfusion on ultrastructure changes in intrahepatic bile duct epithelial ceils of the rat with liver ischemia reperfusion injury. Methods The model of partial rat orthotopic liver ischemia reperfusion was used. Fifty-four rats were randomly divided into sham operation group （SO）, initial hepatic artery reperfusion （IAR） group and initial portal reperfnsion （IPR） group. The liver tissue samples were collected at 0.5,2.0,4.0,12.0 h after ischemia reperfusion in both IAR group and IPR group. The ultrastructure of intrahepatic bile duct epithelial cells was observed under transmission electron microscopy. The morphometric analysis on the mitochondria was processed by the computer image analysis system. Results （ 1 ） In group IAR and group IPR, the injury of intrahepatic bile duct epithelial cells was aggravated gradually along with the reperfusion. The ultrastructural changes were observed, such, as mitochondria enlarged, cristae blurred or disappeared,microvilli decreased; （2） In group IPR 0.5 h and group IPR 2 h,the injury of intrahepatic bile duct epithelial cells was not significantly aggravated as compared with that in group IAR at the same time：there was no significant difference in the mitochondrial average area, average perimeter and numerical density （P〉0.05）.On the contrary,in group IPR 4 h and group IPR 12 h,the injury was more serious than that in group IAR at the same time： the mitochondrial average area was enlarged and average perimeter increased significantly （P〈 0.05） at 4 h and 12 h after ischemia reperfusion,and the numerical density at 12 h after ischemia reperfusion decreased significantly （P〈 0.05）. Conclusion Compared with IPR, IAR can protect the uhrastructure in intrahepatic bile duct epithelial cells of the rat against ischemia reperfusion injury.