老龄大鼠脑缺血-再灌注神经细胞凋亡变化规律研究

目的　比较研究青年与老龄大鼠脑缺血再灌注 (I/R)后超微结构与神经细胞凋亡特征。方法　采用线栓法建立急性局灶性脑缺血再灌注损伤模型 ,观察缺血 3h及再灌注 3、6、12、2 4和 72 h脑组织超微结构变化及细胞凋亡。结果　老龄大鼠脑缺血 3h和 I/R12 h脑梗死面积较青年大鼠增大。随着 I/R时间延长 ,脑组织细胞损伤逐步加重 ,老龄大鼠较青年大鼠严重。细胞凋亡随着 I/R时间延长而明显增加 ,老龄大鼠出现的早、持续时间长。结论　老年脑缺血再灌注脑梗死面积增大、超微结构损伤和细胞凋亡出现得早且严重。

Study on changes of neuron apoptosis after focal cerebral ischemia/reperfusion in the aged rats

Objective To study ultrastructured change and neuron apoptosis after focal cerebral ischemia/reperfusion(I/R) in the aged rats. Methods The aged SD rats (20-21 months) and the young (4-5 months) were subjected to 3 hours of middle cerebral artery occulsion with the intraluminal filament technique, followed by reperfusion for 3 hours, 6 hours, 12 hours, 24 hours, 72 hours. The ultrastructure of brain, infarct zone and neuron apoptosis were observed. Results The cerebral infarct zone increased in the aged rats with ischemia for 3 hours and I/R for 12 hours compared with those in the young. The brain injury was obviously deteriorated with I/R time longer, which was serious in the aged than that in the young. The neuron apoptosis increase with I/R time longer, and showed earlier and lasted longer in the aged. Conclusion The cerebral injury is serious and neuron apoptosis increase shows early and lasts longer.