内源性NGF在缺血性老年大鼠部分脑区及小脑中的表达

目的 探讨缺血性老年大鼠部分脑区及小脑与神经生长因子（neve growth factor,NGF)之间的关系。方法 用夹闭两侧颈总动脉法建立不完全性脑缺血动物模型，将SD大鼠随机分成正常对照组（A组）、假手术组（B组）、缺血30min，再灌注6h（C组）、12h（D组）、24h（E组）、48h（F组）、7d(G组）和14d（H组），用免疫组织化学SLAB染色法检测部分脑区神经元及小脑NGF的表达。在透射电镜下观察各组神经元超微结构变化。结果 除A，B组外，各组顶叶皮质神经元均有NGF表达，其中E组和G组中量表达，各组海马均有少量表达，各组额叶少量表达，小脑均没有表达；再灌注超过48h组海马神经元和小脑蒲肯野细胞损伤较重，顶叶皮质神经元轻度水肿。结论 老年大鼠在受到缺血性脑损伤时，内源性NGF对脑组织具有一定的保护作用。

Expression of endogenous NGF in brain areas and cerebella of aged rats on reperfusion following cerebral ischemia

Objective To study the relationship between endogenous NGF and reperfusion following cerebral ischemia in brain areas and cerebella of the aged rats. Methods Model of incomplete cerebral ischemia was induced by clipping common carotid artery. A total of 36 aged SD rats were divided randomly into 8 groups: normal control group (group A) , sham - operation group (group B), reperfusion 1h, 12h, 24h, 48h, 7d and 14d groups after cerebral ischemia for 30 min (group C, D, E, F, G and H) . The expression of NGF was examined by immunohistochemistry and neuronal ultrastructural changes were observed by transmission electron microscope (TEM) at different time after reperfusion. Results Immunohistochemistry showed NGF expression in the parietal cortical neurons of all groups except group A and B, moderate expression in group E and D, light NGF expression in hippocampal neurons of all groups and low NGF expression in the frontal neurons of all groups. There was liffle expression of NGF in cerebella of all groups. Ultrastructure of hippocampal neurons and Purkinje cells of the aged rats with ischemia/reperfusion over 48h was more severely damaged. The parietal cortical neurons were slightly swollen. Conclusion Endogenous NGF has a protective role in damaged brain of aged rats.