天麻素对局灶脑缺血再灌注海马中BDNF及TrkB的影响

目的 探讨天麻素对局灶性脑缺血再灌注损伤的海马脑源性神经营养因子及其受体TrkB含量变化的影响.方法 120只SD大鼠体重200～2209,随机分为三组:假手术组(n=40),局灶脑缺血再灌注组(n=40)和天麻素治疗组(n=40).线栓法制备大脑中动脉梗阻(MCAO)模型,药物组在脑缺血再灌注即刻和12h腹腔注射天麻素,模型组和假手术组均注射等量生理盐水.分别在缺血再灌注2h、4h、6h、12h和24h处死动物,运用RT-PCR技术检测缺血侧海马组织内BDNF和TrkB的mRNA的表达变化.结果 再灌注损伤后,损伤侧海马组织内BDNF和TrkB的mRNA表达均增高.在天麻素治疗组中BDNF和TrkB的mRNA于再灌注2h上升,4h达高峰.结论 脑缺血后损伤侧海马神经元内BDNF和TrkB的mRNA含量增多,可能有利于受损神经元的修复.

The effects of gastrodin on the BDNF and TrkB in hippocamp following focal cerebral ischemia/reperfusion inrats rats

Objective To Investigate the expressions of BDNF and TrkB in hippocamp after focal cerebral ischemia/reperfusion （I/R）, and to study the neuroprotective effects of gastrodin. Methods 120 Sprapgue Dawley rat weighing 200-220g were randomly divided into three groups：sham-operated group （n=40）, I/R group （n=40） and gastrodin -treated group （n=40）. Temporary middle cerebral artery occlusion （MCAO） model was applied. Immediately and 12 h after reperfusion, rat received intraperitioneal injections of gastrodin for the gastrodin -treated group and same volume physiological saline for the I/R group and sham-operated group. The expression of BDNF and TrkB mRNA were measured with methods of RT-PCR respectively at 2h, 4h, 6h, 12h and 24h after reperfusion in cerebral cortex of rats. Results The expression level of BDNF and TrkB mRNA increased after reperfusion. In gastrodin group BDNF and TrkB mRNA increased significantly at 2 h after reperfusion, peaked at 4h. Conclusion BDNF and TrkB mRNA maybe related to the mechanism of neuronis injury and repairment, gastrodin may have protective effects on iscbemic neurons ofhippocamp by enhanced BDNF and TrkB expression.