NGF对局灶性脑缺血再灌注大鼠顶叶皮质CREB表达的上调作用

为探讨外源性神经生长因子(NGF)对局灶性脑缺血再灌注大鼠顶叶皮质cAMP反应元件结合蛋白(CREB)和磷酸化CREB(p-CREB)表达的影响,用线栓法制作局灶性脑缺血再灌注模型,应用免疫组织化学、WesternBlotting和图像分析方法检测大鼠缺血侧顶叶皮质CREB和p-CREB的表达。结果显示:缺血再灌注组CREB表达较假手术组减少,p-CREB表达高于假手术组(P<0.05);NGF组CREB和p-CREB表达高于缺血再灌注组(P<0.05)。以上结果表明NGF明显上调局灶性脑缺血再灌注大鼠顶叶皮质CREB和p-CREB的表达,NGF对缺血神经元的保护作用可能通过上调CREB和p-CREB的表达来实现。

UPREGULATION EFFECT OF NGF ON THE EXPRESSION OF CREB AND PHOSPHO-CREB PROTEIN DURING FOCAL CEREBRAL ISCHEMIA/REPERFUSION IN RAT PARIETAL CORTEX

In order to explore the effect of nerve growth factor(NGF)on the expression of cyclic AMP response element binding protein(CREB)and phosphorylated-CREB in rat parietal cortex during focal cerebral ischemia/reperfusion(I/R),focal cerebral ischemia/reperfusion model was induced by occlusion of the middle cerebral artery using the intraluminal suture method.The expressions of CREB and phospho-CREB in the ipsilateral parietal cortex of rats were detected with immunohistochemistry and Western Blotting.The positive products of CREB and phospho-CREB were analyzed by image analysis system.The results showed that the expression of CREB in the ipsilateral parietal cortex reduced and the expression of phospho-CREB increased in ischemia/reperfusion(I/R)group compared with sham group(P<0.05).But after treatment with NGF,the quantities of both CREB and phospho-CREB were found to be higher than that of I/R groups(P<0.05).The above results indicate that NGF can upregulate the expression of CREB and phospho-CREB in the ipsilateral parietal cortex after focal cerebral ischemia/reperfusion and CREB may be involved in the protective mechanism of NGF to ischemic neurons.