脑缺血再灌注后脑内脑源性神经营养因子的基因表达与调节

The brain derived neurotrophic factor mRNA level changes following trainsient focal brain ischemia and reperfusion in brain

目的 :探讨脑缺血再灌注损伤后脑内脑源性神经营养因子 ( BDNF) m RNA水平的变化规律 ,推测BDNF对损伤病理的影响。方法 :线栓法制作大鼠脑缺血再灌注模型 ,原位杂交检测大鼠海马神经元内BDNFm RNA,图象分析间接定量 BDNFm RNA水平。结果 :( 1 )脑缺血及缺血再灌注均能诱导双侧海马神经元BDNFm RNA水平增高 ;( 2 )缺血损伤过重后海马神经元 BDNFm RNA水平增高的程度反而小 ;( 3 )再灌注后BDNFm RNA的水平继续升高 ,高峰值出现在 1 2小时 ,至 72小时降至对照组水平 ;两侧海马的变化趋势类似。结论 :海马神经元在脑缺血及再灌注损伤后将升高 BDNFm RNA的表达以保护神经元 ,海马各区 BDNFm RNA基础水平与海马神经元病理改变程度呈负相关。

Objective: To study the change of brain derived neurotrophic factor mRNA (BDNFmRNA)in hippocampus and the effect of BDNF on the hippocampus neurons after focal cerebral ischemia and reperfusion in rats.Methods:The level of BDNFmRNA was measured in the rat hippocampus using in situ hybridization.Results :(1)The level of BDNFmRNA in the bilateral hippocampus was increased after cerebral ischemia and reperfusion.(2)The lower level of BDNFmRNA in the hippocampus with serious ischemia was found than that with slight ischemia.(3)The level of BDNFmRNA following the reperfusion was increased continuously.It was the highest at 12 hours and recovered basal level at 72 hours after the reperfusion.Conclusion: The regional basal BDNFmRNA level showed here positively correlated with cellular resistance to ischemic damage,and it was consistent with the hypothesis of a neuroprotective role of BDNF.