大鼠局灶-局灶缺血预处理后脑组织c-fos的表达及神经细胞凋亡测定

目的:探讨脑缺血预处理后脑组织原癌基因c-fos的表达及其对神经细胞凋亡的影响.方法:90只大鼠随机等分为假手术组(A组)、假预处理缺血组(B组)和预处理缺血组(C组)3组.采用Longa法建立局灶脑缺血(MCAO模型,短暂性脑缺血20 min作为预处理(PC,PC)后24 h给予永久性MCAO(PMCAO.各组大鼠均于第2次手术12 h(n=25)或24 h(n=5)后用红四氯氮唑(TTC)染色观察脑梗死的体积,采用流式细胞仪检测大鼠前脑皮质细胞凋亡率,采用原位杂交和免疫组织化学方法对脑缺血再灌注后前脑皮质c-fos mRNA和蛋白进行检测.结果:C组PMCAO后12 h、24 h脑梗死体积较B组减小(P＜0.05);C组前脑皮质c-fos mRNA的表达高于A、B组(P＜0.05或0.01,c-fos)蛋白的表达高于A组(P＜0.01、低于B组(P＜0.05), 而凋亡细胞百分率较B组下降(P＜0.01).结论:脑缺血预处理可诱导c-fos mRNA和蛋白的表达,并抑制缺血诱导的神经细胞凋亡.

Detection of neural apoptosis and expression of c GAAB2 fos following focal ischemical preconditioning on middle cerebral artery in rats

Aim: To detect the neural apoptosis and expression of c-fos following focal ischemical preconditioning on middle cerebral artery in rats.Methods: A total of 90 rats were randomly divided into preconditioning (PC) permanent middle cerebral artery occlusion (PMCAO) group, sham surgery (SS) PMCAO group, SS SS group. Temporary MCAO model was established by Longa (20 min) in PC, and after 24 h PMCAO was established. Infarction size was measured using TTC staining and the apoptotic neural cells were detected by flow cytometry, c-fos mRNA and protein in the rat neocortex were detected by in situ hybridization and immunohistochemistry, respectively at 12 h and 24 h after PMCAO. Results: At 12 h and 24 h after PMCAO, the infarction size in PC PMCAO group was smaller than that of SS PMCAO (P< 0.05 ), the expression of c-fos mRNA and protein was higher than those in SS SS group (P<0.01), whicle the apoptotic cell percentage was lower (P<0.01).Conclusion: Focal cerebral ischemic preconditioning can induce expression of c-fos mRNA and protein and suppress the neural apoptosis following severe ischemia.