实验性新生儿缺氧缺血脑损伤模型鼠脑细胞凋亡动态变化

Observation of neuron apoptosis following unilateral cerebral hypoxia-ischemia in the neonatal rat

目的 探讨新生儿缺氧缺血脑损伤 (HIE)后皮质、海马细胞调亡现象和动态过程。方法 制作标准化HIE实验模型 ,应用DNA原位末端标记 (TUNEL)、HE染色、电镜方法 ,对凋亡出现时间和强度进行观察和比较。结果 缺氧缺血后新生鼠脑细胞死亡具有典型凋亡特征 ,光镜、电镜观察到核膜皱缩、染色质凝聚 ,阳性TUNEL着色细胞核。随着缺血时间的增加 ,细胞凋亡数逐渐增加 ,皮质约在 18小时点、海马 40小时点达高峰。结论 HIE中神经细胞死亡的重要形式之一是细胞凋亡。其细胞凋亡呈动态过程 ,且皮质。

Objective To investigate apoptosic mechanisms of cortex and hippocampus in the brain following traditional model of neonatal hypoxia-ischemia(HIE).Methods The traditional model of neonatal HIE was made. Terminal deoxy-nuleotidyl transferase-labeling(Tunel), HE staining and electron-microscope were used to observe and compare the time and degree of apopticus cells in the cortex and hippocampus.Results The typical character of apoptosis was found in neonatal brain cells following hypoxia-ischemia. Cells shrink, chromatin condensation under microscope,positive cells identified in situ labeling were observed. Apoptosis cells increased following ischemia time extending, and the peak time in cortex is 18h point,that in hippocampus is 40h point. Conclusion Apoptosis is one important form of celldsath of HIE.Dynamic process of apoptosis is different in the cortex and hippocampus after HIE.