蛛网膜下腔出血大鼠脑干组织谷氨酸转运体的表达及尼莫地平的影响

目的探讨谷氨酸转运体（EAATs）在蛛网膜下腔出血（ShH）大鼠脑干表达的动态变化。方法采用枕大池二次注血法建立Wistar大鼠SAH模型。应用颅多普勒超声检测和RT-PCR方法，分别观察蛛网膜下腔出血大鼠基底动脉血流速度和谷氨酸转运体在脑干的变化。结果①超声检测显示与对照组相比，枕大池注血大鼠第1天基底动脉血流加快，第7天达到高峰，第14天血流速度下降，第21天未见明显变化，表明大鼠出现了脑血管痉挛（CVS）。尼莫地平给药组大鼠的基底动脉血流速度均比SAH组血流速度慢。②RT-PCR结果显示在第1天和7天SAH模型组脑干EAAT-1、EAAT-2和EAAT-3mRNA的表达下降，第14天上升，其对应的尼莫地平治疗组EAAT1—3mRNA的表达均高于SAH组；而在第21天SAH模型组与其对应的尼莫地平治疗组均上升，但两者相比未见明显差异。结论尼莫地平可以明显的减轻SAH发生后CVS的程度，并使EAAT-1、EAAT-2和EAAT-3mRNA的表达水平增高，提示EAAT-1、EAAT-2和EAAT-3可能参与了大鼠CVS的形成。

The expression of the glutamate transporter subtypes in subarachnoid hemorrhage(SAH) brain stem and effect of nimodipine on the expression

Objective to study the change of expression of the glutamate transporter subtypes （EAAT-1,EAAT-2,EAAT-3） in subaraehnoid hemorrhage（SAH） rat brain stem.Methods establish a reliable models of subarachnoid hemorrhage（SAH） by double injections of blood into cistern magna in Wistar rats. Application of transeranial doppler ultrasound and RT-PCR method for detected the change of basilar artery blood flow velocity （Vba） and glutamate transporters of after subaraehnoid hemorrhage in rat brainstem. Ultrasonic testing showed compared with a control group,the basilar artery blood flow to significantly speed up at day 1st after injections of blood into cistern magna in rats,at 7th day blcod flow to the highest,at the 14th days the blcod flow velocity began to decline, at the 21th days showed no significant change. The speed of the basilar artery blood flow of nimodlpine delivery groups rats when compared with SAH model rats were slow.The resulths showed that the rats have produced cerebral vasospasm.The RT-PCR. Results showed the at day 1,7 th day the decreased expression of EAAT-1,EAAT-2,EAAT-3 mRNA of SAH model rats in rat brain stem,at 14 th day,21 th day the expression of EAATs mRNA gradually inereased, and its corresponding nimodipine delivery groups the expression of EAATs mRNA of rats were always higher than SAH model rats. Conclusion the nimodipine can significantly reduce the extent of CVS after SAH and increased mRNA expression levels of EAAT-1, EAAT-2, and FAAT-3, the results indicated that EAAT-1,EAAT-2,and FAAT-3 may be involved in the formation of cerebral vasospasm of rats.