大鼠脑缺血再灌注后脑源性神经营养因子的表达及意义

目的　研究脑局灶缺血再灌注后脑源性神经营养因子 (BDNF)的表达规律及其意义。方法　健康雄性Wistar大鼠 30只 ,随机分为正常对照组、假手术组和缺血再灌注组 ,按照改良的栓线法建立大脑中动脉缺血再灌注大鼠模型。用免疫组织化学方法检测BDNF在脑组织中的表达情况。结果　BDNF免疫阳性表达在缺血再灌注组的梗死中心区梗死灶边缘带有显著增强的阳性表达。再灌注 15min开始增多 ,再灌注 1h明显增多 ,2h达到高峰 ,4h开始下降 ,2 4h恢复至正常对照组水平。结论　缺血再灌注损伤可诱导BDNF极早表达 ,并迅速升高 ,有利于缺血再灌注损伤后神经细胞的存活及后期神经功能恢复

Expression of BDNF protein in rat after focal cerebral ischemia and reperfusion

Objective To study the expression of brain-derived neurotrophic factor(BDNF) protein in MCAO rat model and to discuss the protective mechanisms.Methods The rats in ischemia-reperfusion group were operated according to the modified MCAO method. The method of SP immunostaining was used to study the expression of BDNF protein.Results The most marked increase in BDNF protein expression occurred in neurons in the center and the border zone of the infarct.Fifteen minutes after reperfusion, a diffuse expression of BDNF was found, which further intensified until 1 h. The level of BDNF attained the peak at 2 h,began to decline at 4 h and reached the control level at 24 h.Conclusions High level of BDNF expression persists for a short time following ischemia-reperfusion injury of brain. It is an endogenous self-protective mechanism for helping to maintain neuron survival and to recover neural function.