新生儿缺氧缺血性脑病海马细胞凋亡的实验研究

An Experiment Report for the Hippocampus Apoptosis in Model of Neonatal Hipoxic-ischemic Encephalopathy

目的：探讨新生儿缺氧缺血性脑病（ＨＩＥ）中海马迟发性神经元死亡现象，研究其凋亡的作用机理。方法：通过ＨＩＥ的动物模型，应用ＤＮＡ电泳、电镜、原位末端标记技术等手段，分别对缺氧３ｈ完成后１、４、１８、２４、４０、７２ｈ及７ｄ组和对照组海马凋亡细胞形态、密度、时间进行观察比较。结果：光镜、电镜显示细胞皱缩、染色质边集、出现凋亡小体，ＤＮＡ电泳图谱显示梯状形态，原位标记显示海马各区标记阳性的细胞，定量比较显示ＨＩＥ后４０ｈ点海马细胞凋亡最明显，其中ＣＡ１区持续至７ｄ以后。结论：在ＨＩＥ中细胞死亡存在着凋亡作用；

Objective:To study the potential role of apoptosis and delayed cell death of hippocampus following neonatal hypoxia-ischemia (HIE).Method:establishing the animal model of HIE and observing cell apoptosis in the hippocampus after permanent ischemia 1,4,18,24,40,72 h,7 d with control group. Using electrophoresis, and electron-microscope, terminal deoxynuleotidyl transferase nick end labeling(Tunel) technique,the shape,density and time of the cell death have been observed and compared in the apoptotic cells.Result:The morphologic changes of cell apoptosis including cell shrinkage,chromatic condensation and apoptotic bodies, ladder electrophoresis,DNA fragmentation were found. The peak of cell apoptosis was at 40h after hypoxia-ischemia.It was maily located in CA 1 region.Conclusion:The cell death of HIE was caused by necorosis and apoptosis with showing delayed neuronal death in the hippocampus of immature brain after HIE.