次声作用后大鼠CA1区GLAST mRNA表达变化

Alterations of expressions of GLAST′s mRNA in CA1 of rats after infrasonic damage

目的:研究次声作用后大鼠CA1区GLAST(谷氨酸转运蛋白亚型Ⅰ)mRNA表达水平变化及其意义。方法:SD大鼠80只随机分为对照组及次声作用1、7和14次组,将大鼠暴露于8Hz 130dB次声,2h/次/d,按上述规定次数在次声压力仓内作用后,采用原位杂交、实时定量PCR法检测CA1区的GLAST mRNA表达变化情况。结果:与对照组GLAST mRNA比较,8Hz、130dB的次声作用1次后,GLAST mRNA表达水平即发生了上调,7次组显著上调,14次组则略有恢复,但表达水平仍高于对照组。结论:次声脑损伤后,谷氨酸在细胞外堆积,产生神经毒性,可能与谷氨酸转运蛋白下调,重吸收障碍有关。上调GLAST或促进其核酸表达可能对次声脑损伤后脑组织有保护作用。

Objective：To study the alterations of expressions of GLAST＇s mRNA in CA1 of rats brain after infrasonic damage so as to probe into the function of GLAST in infrasonic damage. Method： Eighty SD rats were randomized into four groups： control group and 1-time, 7-time,14-time infrasonic damage groups. Rats were exposed to 8Hz 130dB infrasonic damage, as 2h/time/d. Expression of GLAST＇s mRNA were detected by hybridization in situ method and reahime PCR method. Result： Expressions of GLAST＇s mRNA had a tendency of up-regulation after infrasonic damage. It showed that in 1-time group there was up regulation of GLAST＇s mRNA compared with that of control group. In 7-time and 14-time group, the up-regulation of GLAST was more severe than that of control group. Conclusion： The increase of glutamate produce the neurotoxicity and may be concerned with the down regulation of GLAST after infrasonic brain damage. The down-regulation of GLAST may lead to the disorder of glutamate＇s reabsorption and result in secondary brain damages. Therefore the up-regulation of GLAST＇s mRNA may provide protection effect for the brain after infrasonic damage.