Abstract:

Objective To explore the expression of glutamate interacting protein (GRIP) and its relationshipwith glutamate receptor 2 (GluR2) after ischemia/reperfusion in rats brain.Methods Thirty-six male Sprague Dawley rats were randomly divided into ischemia-reperfusiongroup and sham group. Middle cerebral artery occlusion (MCAO) was achieved with the use of anintraluminal filament to occlude the left MCA. Then the reperfusion was applied for different lengthof time. Sham-operations were also done (n=6). At 1, 6, 12, 24 and 72 hour after reperfusion, allrats were decapitated. Western blot was used to determine the expression of GRIP, GluR2 on themembrane and in the cytoplasm.Results Western blot showed that at 1h, 6h, 12h, 24h and 72h after reperfusion, the ratio of GRIPin operation group to that in sham group were from 1.11±0.21, 1.42±0.03, 1.49±0.03, 1.31±0.03 and1.20±0.03. It showed significant increase (P <0.01) compared with sham except 1h group. The ratioof GluR2 on the membrane to that in the cytoplasm were 1.38±0.12, 1.78±0.11, 3.53±0.15, 4.62±0.24and 0.87±0.08 respectively. It also exhibited significant than sham group (P <0.01) except 1h group.Conclusion Both GRIP and GluR2 on the membrane increased obviously after ischemiareperfusion,which may take an important role in the AMPA receptor mediated excitotoxic injury.【

Key words: Brain ischemia; Reperfusion; Receptor; glutamate

摘要： 目的 研究脑缺血再灌注模型半暗带皮质中谷氨酸相互作用蛋白（glutamate receptor interactingprotein，GRIP）表达的变化及其与谷氨酸受体2（glutamate receptor 2，GluR2）的关系。方法 36只SD雄性大鼠随机分为缺血再灌注1、6、12、24、72 h组和假手术组（每组6只大鼠），缺血再灌注组线栓法制作大脑中动脉闭塞2 h后再灌注模型，并于再灌注后不同时间点处死取脑，Westernblot测定GRIP蛋白的含量以及胞浆中和胞膜上GluR2的含量变化。结果 Western blot结果显示脑缺血再灌注后1、6、12、24、72 h缺血半暗带胞浆GRIP含量与对照组比值分别为1.11±0.21、1.42±0.03、1.49±0.03、1.31±0.03和1.20±0.03，除1 h组与对照组无明显差异（P =0.65），其余各组与对照组差异有统计学意义（均P <0.01）。缺血半暗带GluR2在胞膜上与胞浆中含量的比值分别为1.38±0.12、1.78±0.11、3.53±0.15、4.62±0.24和0.87±0.08，除1 h组与对照组无明显差异（P =0.498），其余各组与对照组差异有统计学意义（均P <0.01）。结论 脑缺血再灌注时，半暗带区GRIP表达增加，GluR2在胞膜上的含量也增加，可能在AMPA受体介导的兴奋性毒性损伤中发挥重要作用。

关键词: 脑缺血; 再灌注; 受体; 谷氨酸