缺血缺氧性脑损伤后神经干细胞和脑组织再生的研究

Investigation of Neural Stem Cell and Regeneration after Hypoxic Ischemic Brain Injure

目的:研究缺血缺氧性脑损伤(hypoxic-ischemic brain injure,HIBI)后神经干细胞(neural stem cells,NSCs)的增殖、迁移和分化及脑组织的再生能力。方法:大鼠缺血缺氧性脑损伤后腹腔注射5-溴脱氧尿苷(BrdU),损伤后在各观察点,动物麻醉后取脑,石蜡包埋,冠状切片,行HE染色和免疫组织化学染色。结果:缺血缺氧性脑损伤后1周,海马颗粒细胞层下区(Subgranular zone,SGZ)和脑室管膜下区(subventricular zone,SVZ)可见小蓝紫色核的细胞;损伤后2周,海马可见具有毛刷状轴/树突层的神经元再生,大脑皮层未见神经元再生。缺血缺氧性脑损伤后,SGZ和SVZ的背外侧角及外侧壁处均可见BrdU+细胞、Nestin+细胞和BrdU+-Nestin+双阳性细胞;并可见这些细胞沿胼胝体向外迁移。结论:缺血缺氧性脑损伤后,海马颗粒细胞层下区和脑室管膜下区的神经干细胞增殖,脑室管膜下区的神经干细胞沿胼胝体向外迁移,海马神经元可完全再生,大脑皮层神经元未见再生。

Objective：To investigate the changes of neural stem cells （NSCs） of newborn rats following hypoxicischemic brain injure （HIBI）. Methods ..Rats received injection of BrdU twice a day for three days after HIBI ,and the rats were sacrificed at different time after HIBI. Then the brains were removed and emdedded in paraffin. Coronal sections were made for further HE and immunohistochemical assessment. Results：After HIBI a week,there were cells of small blue nuclear at Subgranular zone （SGZ） and subventricular zone （SVZ）;after HIBI two week,there was complete regeneration at hippocampus and no regeneration at cortex of cerebrum. After HIBI,there were cells of BrdU-positive ,Nestinpositive,BrdU-Nestin double positive at SGZ and SVZ;and cells at SVZ migrated along the corpus callosum. Conclusion： After HIBI,neural stem cells proliferate at SGZ and SVZ,and migrate along the corpus callosum at SVZ;there is complete regeneration at hippocampus and no regeneration at cortex of cerebrum.