降钙素基因相关肽对局灶性脑缺血再灌注大鼠海马CREB和磷酸化CREB的上调作用

目的:探讨外源性降钙素基因相关肽(CGRP)对局灶性脑缺血再灌注大鼠海马CREB和磷酸化CREB(p- CREB)表达的影响。方法:制作局灶性脑缺血再灌注模型实验组并给予CGRP,应用免疫组织化学、Western印迹和图像分析方法检测大鼠海马CA1区CREB和p-CREB表达。结果:缺血再灌注组CA1区CREB表达较假手术组减少,CGRP组CA1区的CREB表达高于缺血再灌注组。缺血再灌注组CA1区p-CREB表达高于假手术组,CGRP组p-CREB表达多于缺血再灌注组。结论:CGRP上调局灶性脑缺血再灌注大鼠海马CREB和p-CREB的表达,CGRP对缺血神经元的保护作用可能是通过上调神经元内CREB和p-CREB来实现的。

CGRP upregulates the expressions of CREB and phospho-CREB protein during focal cerebral ischemia/reperfusion in rat hippocampus

Objective:To investigate the effect of calcitonin gene-related peptide(CGRP) on the expression of cyclic AMP response element binding protein (CREB) and phosphorylated-CREB in rat hippocampus during focal cerebral is- chemia/reperfusion(I/R).Methods:Focal cerebral isehemia/reperfusion model was induced by occlusion of the right middle cerebral artery using the intraluminal suture method.The expressions of CREB and phospho-CREB protein in the right hippocampal CA1 region were detected with immunohistochemistry and Western blotting and the positive products were analyzed by using image analysis system.Results:The expression of CREB protein in the right hipp- ocampal CA1 region in ischemia/reperfusion(I/R) group reduced as compared to that in the sham group,while the ex- pression of CREB protein increased in CGRP group in comparison with that in I/R group.Phospho-CREB was barely detected in the right hippocampal CA1 region in the sham group and it increased more significantly in I/R group than that in the sham group.Besides,the expression of phospho-CREB in the right CA1 region in CGRP group increased further as compared to that in I/R group.Conclusion:CGRP upregulates the expressions of CREB and phospho-CREB in the ischemic neurons of the hippocampus during focal cerebral ischemia/reperfusion and CREB is probably involved in the protective mechanism of CGRP to ischemic neurons.