全脑缺血再灌注诱导大鼠海马CA1区GluR6巯基亚硝基化的机制

Mechanism of Nitrosation of GluR6 Thiol in Rat Hippocampal CA1 Region Induced by Global Cerebral Ischemia-reperfusion

目的用大鼠全脑缺血模型探讨全脑缺血再灌注诱导大鼠海马CA1区GluR6巯基亚硝基化的机制。方法将78只雄性SD大鼠随机分为假手术组(Sham组)、全脑缺血再灌注组(I/R组)、给药组(7-NI组、GSNO组、SNP组、NS102组)及溶剂对照组[生理盐水(Saline)组、DMSO组],每组6只。采用四动脉结扎去结扎法构建大鼠全脑缺血再灌注模型。运用生物素转化法检测蛋白质的巯基亚硝基化,聚丙烯酰胺凝胶电泳、免疫印迹方法对GluR6巯基亚硝基化水平进行分析研究。结果全脑缺血再灌注后,I/R组GluR6巯基亚硝基化水平高于Sham组,差异有统计学意义(P<0.05),7-NI组GluR6巯基亚硝基化水平相比I/R组明显降低,差异有统计学意义(P<0.05),溶剂DMSO组与I/R组相比差异无统计学意义(P>0.05);GSNO组和SNP组GluR6巯基亚硝基化水平比I/R组明显降低,差异有统计学意义(P<0.05),溶剂Saline组与I/R组相比差异无统计学意义(P>0.05);NS102预处理组GluR6巯基亚硝基化水平比I/R组明显降低,差异有统计学意义(P<0.05),溶剂DMSO组与I/R组相比差异无统计学意义(P>0.05)。结论7-NI、GSNO、SNP和NS102都能抑制脑缺血再灌注诱导的GluR6巯基亚硝基化。nNOS介导产生的内源性NO介导全脑缺血再灌注诱导的大鼠海马CA1区GluR6巯基亚硝基化,并受外源性NO影响;全脑缺血再灌注通过激活KA受体诱导大鼠海马CA1区GluR6发生巯基亚硝基化。

Objective To investigate the mechanism of GluR6 thiol nitrosylation in rat hippocampal CA1 region induced by global cerebral ischemia-reperfusion in a rat model of global cerebral ischemia.Methods 78 male Sprague-Dawley rats were randomly divided into sham operation group(Sham group),global cerebral ischemia-reperfusion group(I/R group),and drug-administered group(7-NI group,GSNO group,SNP group,NS102 group).And the solvent control group[saline group,DMSO group],6 in each group.A rat model of global cerebral ischemia-reperfusion was established by four-arterial ligation and ligation.The biotintransformation method was used to detect the sulfhydryl nitrosylation of proteins,and the phosphination level of GluR6 thiol was analyzed by polyacrylamide gel electrophoresis and immunoblotting.Results After global cerebral ischemia-reperfusion,the level of GluR6 thiol nitrosylation in the I/R group was higher than that in the Sham group,the difference was statistically significant(P<0.05).The level of GluR6 thiol nitrosylation in 7-NI group was significantly lower than that in I/R group,the difference was statistically significant(P<0.05).Solvent DMSO group and I/R group There was no significant difference between the two groups(P>0.05).The nitrosation level of GluR6 in the GSNO group and the SNP group was significantly lower than that in the I/R group,the difference was statistically significant(P<0.05).There was no significant difference between the Saline group and the I/R group(P>0.05).The GluR6 sulfhydryl nitrosylation level in the NS102 pretreatment group was significantly lower than that in the I/R group,the difference was statistically significant(P<0.05).There was no significant difference between the solvent DMSO group and the I/R group(P>0.05).Conclusion 7-NI,GSNO,SNP and NS102 can inhibit GluR6 sulfhydryl nitrosylation induced by cerebral ischemia-reperfusion.nNOS-mediated endogenous NO mediates GluR6 sulfhydryl nitrosylation in rat hippocampal CA1 region induced by global cerebral ischemia-reperfusion and is affected by exogenous NO;global cerebral ischemia-reperfusion activates KA receptor Induction of thiol nitrosylation of GluR6 in the hippocampal CA1 region of rats.