【摘要】 目的探讨血小板内皮细胞粘附分子-1(PECAM-1/CD31)在大鼠肺缺血-再灌注损伤过程中的作用。方法建立大鼠单肺原位热缺血-再灌注模型。将清洁SD大鼠随机分为对照组和实验组(缺血-再灌注组),应用流式细胞术测定大鼠肺缺血60 m in后再灌注损伤不同阶段(0,2,4,6,8 h)血液中中性粒细胞和淋巴细胞PECAM-1/CD31的变化情况。并采用光镜和透射电镜观察组织、细胞形态及亚显微结构,确定凋亡发生情况。结果肺缺血-再灌注后,血液中中性粒细胞和淋巴细胞PECAM-1/CD31均开始升高,2 h达到高峰(P<0.01),然后逐渐下降,至6和8 h基本恢复到缺血-再灌注前水平。肺缺血-再灌注后,肺组织透射电镜观察可见肺泡Ⅱ型上皮细胞增多,并且不同程度出现形态学改变,细胞体积缩小变圆,细胞核呈多边形,核被膜外折或内陷,核固缩并边集在核膜下呈月牙状或腰带状,胞浆浓缩,胞浆内嗜锇性板层体减少,排空增多,细胞膜上微绒毛减少或消失,并可见凋亡小体,提示细胞凋亡发生。此种亚显微结构的改变在再灌注2 h最为明显,与PECAM-1的变化相似。结论血小板内皮细胞粘附分子-1参与并介导了肺缺血-再灌注损伤的病理过程,可作为肺缺血-再灌注损伤的标志分子。更多还原

【Abstract】 Objective To evaluate the effect of PECAM1/CD31(platelet endothedial cell adhesion molecule-1) in ischemia-reperfusion induced pulmonary injury of rats. Methods Single lung in situ warm ischemia-reperfusion animal model was established,and SD rats were divided into the control group and test group(ischemia-reperfusion).The rats was subjected to 60 min lung ischemia followed by 0,2,4,6 or 8 h of reperfusion separately.At the end of reperfusion,expression of PECAM-1/CD31 in neutrophilic granulocytes and lymphocytes from blood was detected by using FCM method.Histology of lung,morphology and ultrastructural changes of cells were examined by microscope and transmission electron microscope to determine apoptosis. Results PECAM-1/CD31 expression started to increase after reperfusion,peaked at tie 2 h(P<0.01)after reperfusion and then gradually decreased to basal level at the 6 and 8 h.Proliferation of alveolar type Ⅱendothelial cells,accompanied by ultrastructural morphological changes were observed after reperfusion.Moreover,the membrane microvilli decreased and even disappeared,apoptotic body was also found,which suggested apoptosis formed.This ultrastructural change was prominent at 2 h after reperfusion,which was similar to the change of PECAM-1. Conclusion PECAM-1/CD31 may involve in and mediate the ischemia-reperfusion induced pulmonary injury,which can be used as the marker molecule for the latter.更多还原