脑缺血再灌注后神经元和内皮细胞凋亡的差异与Bcl—2和P53表达的意义

目的：探讨大鼠局灶性脑缺血再灌注后神经细胞和血管内皮细胞凋亡的差异及其与Bcl-2和p53蛋白表达的关系。方法：应用原位末端标记技术和免疫组化方法，检测神经细胞和血管内细胞凋亡及Bcl-2和p53蛋白表达，结果：在缺血周围区，缺血再灌注2h神经细胞和内皮细胞凋亡开始增多，12－24h达高峰，之后逐渐减少，7－14d降至假手术组水平；血管内皮细胞凋亡迟于神经元凋亡12－24h,Bcl-2蛋白表达于缺血再灌注2h开始增强，12－24h达高峰，之后逐渐下降，至7－14d接近假手术组水平，p53蛋白表达于缺血再灌注6h开始增高，24－48h达高峰，之后逐渐下降，至14d与假手术组已无显著性差异。结论：脑缺血再灌注损伤后血管内皮细胞凋亡迟于神经元凋亡，Bcl-2和p53蛋白参与细胞凋亡的调节。

DIFFERENCE BETWEEN NEURON AND ENDOTHELIAL CELL APOPTOSIS AND THE EXPRESSION OF BCL 2 AND P53 AFTER CEREBRAL ISCHEMIA REPERFUSION IN RATS

Objective:To study the differences between apoptotic neuron and endothelial cell and their relationship with the expression of Bcl 2 and p53 proteins after reperfusion of focal cerebral ischemia in rats.Methods:Coronal sections of brain were analyzed using and in situ terminal deoxynucleotdyl transferase mediated biotinylated deoxyuridine triphosphate nick end labeling and immunohistochemical staining methods to observe apoptosis and expression of Bcl 2 and p53.Results:In the ischemic penumbra,the number of apoptotic cells were increased 2 h after reperfusion,peaked at 12 24 h,then decreased successfully for 7 14d.The time of apoptotic endothelial cells was 12 24 h later than that of apoptotic neurons.The expression of Bcl 2 protein began 2 h after reperfusion,peaked at 12 24 h,and decreased for 7 14 d.P53 protein expressed 6 h after reperfusion,peaked at 24 48 h,and lasted for 14 d.Conclusion:The time of apoptotic endothelial cell is later than that of apoptotic neuron.Bcl 2 and P53 proteins play a regulatory role in the apoptotic process.