BDNF,NGF在大鼠局灶性脑缺血的表达变化及葛根素对其影响的实验研究

Expressions of BDNF and NGF in focal cerebral ischemia and the effect of Puerarin in rats

目的观察脑缺血后脑源性神经营养因子(BDNF)及神经生长因子(NGF)含量的变化,并研究葛根素对大鼠局灶性脑缺血后脑内BDNF及NGF含量变化的影响及探讨其对缺血性脑损伤的神经元保护作用。方法拟用大鼠大脑中动脉线栓法(MCAO)建立缺血模型,采用免疫组织化学方法观察BDNF及NGF的表达。结果BDNF在MCAO后6h表达增强,1d达高峰,缺血组到3d达到对照组水平,治疗组在5d时仍有表达,到7d达到对照组水平。NGF在MCAO后1d达高峰并持续到7d,7d之后仍有少量表达,治疗组在14d仍有少量表达。结论脑缺血后神经元内BDNF和NGF的含量增多,可能有利于受损神经元的修复。葛根素可能通过促进BDNF、NGF的表达而保护神经元。

Objective To observe expressions of brain-derived neurotrophic factor（BDNF） and nerve growth factor（NGF） after focal cerebral ischemia, and to study the neuroprotective effects of puerarin. Methods The model of focal cerebral ischemia was established by occluding middle cerebral artery（ MCAO）. Dynamic changes of BDNF and NGF positive neurons at different time were observed with method of immtmohistochemistry. Results Both the number of positive neurons of BDNF and that of NGF increased after 6 hours of ischemia, and reached their peaks at the time of 1 day after ischemia, Compared with treatment group and ischemic group, the levels of BDNF and NGF were higher（ P 〈 0.05） ; then the number of positive neurons of BDNF become normal after 3 days, Compared with treatment group and ischemic group, the levels of NGF were still higher at the time of 14 day. Conclusion BDNF and NGF may be related to the mechanism of neuronic injury and repairment. Puerarin may have protective effects on ischemic neurons.