慢性脑缺血大鼠大脑皮质中的神经生长因子表达

Expression of nerve growth factor in cerebral cortex in chronic cerebral ischemia rats

目的:研究慢性脑缺血时大鼠大脑皮质中神经生长因子(NGF)的表达变化,探讨缺血性脑损伤及修复机制。方法:永久性结扎Wistar大鼠双侧颈总动脉,取慢性脑缺血30、120 d组。行为学测试,免疫组化ABC法染色,计数大鼠大脑皮质中的NGF 阳性神经元数及测量平均灰度值。结果:大鼠慢性脑缺血时,大脑皮质中NGF的表达,第120 d比第30 d及对照组显著增强,而 30 d与对照组无显著性差异,同时伴有学习和记忆力下降。结论:慢性脑缺血时,NGF在大脑皮质中的表达将随时间逐渐增强, 对坏死神经元起保护作用。

Objective： To investigate the expression of nerve growth factor （NGF） in cerebral cortex of chronic cerebral ischemia rats, and to explore the mechanism of cerebral ischemia damage and recovery. Methods： Bilateral common carotid arteries of Wistar rats were ligated permanently to establish ischemia model. The rats were divided into control group, 30 d and 120 d chronic cerebral ischemia groups. The test of behavior was performed. ABC immunohistochemical staining was used and the number and gray density of positive neurons of NGF in cerebral cortex was counted. Results： After chronic cerebral ischemia was developed, the expression of NGF in 120 d group was increased compared with those in 30 day group and control group （P〈0. 05）, but the expression in the 30 d group had no obvious difference with control group. Learning and memory ability of the rats declined during ischemia. Conclusion： During chronic cerebral ischemia, the expression of NGF in cerebral cortex increases with the time, protecting the affected neurons.