水杨酸钠对螺旋神经节Caspase 3mRNA及蛋白表达的影响

目的：水杨酸是阿司匹林的活性成分,是导致耳鸣的主要原因。而本实验主要探讨水杨酸钠对耳蜗螺旋神经节（SGN）调亡相关基因Caspase 3的mRNA及蛋白表达水平的影响,并初步探讨水杨酸钠对耳蜗毒性的机制。方法：分离取出大鼠蜗轴螺旋管,用酶消化后原代培养SGN,采用荧光定量PCR法检测5 mM水杨酸钠处理前后（1 h,3 h,6 h）Caspase 3 mRNA的变化,WesternBlot检测其蛋白的变化情况。结果：5 mM水杨酸钠处理细胞后1 h,Caspase 3 mRNA表达水平没有明显改变（P〉0.05）,但是当水杨酸钠处理3 h后,其表达水平明显上调（P〈0.05）,并呈时间依赖关系。而其蛋白表达水平也同样明显升高（P〈0.05）。结论：本实验取蜗轴螺旋管进行原代培养,获得较多的SGN,而水杨酸钠能上调这些原代培养SGN的Caspase 3 mRNA及蛋白的表达,导致SGN调亡,这对水杨酸钠耳蜗毒性的研究有一定应用价值。

Effects of Sodium Salicylate on Expression of Caspase 3 mRNA and Protein in Spiral Ganglion Neurons

Objective： Salicylate,the active of aspirin,is known to induce tinnitus.To study the effects of sodium salicylate on the expression of caspase 3 mRNA and protein in spiral ganglion neurons（SGN） in rat,and further to explore the underlying mechanism.Methods： SGN from newborn rats were cultured by trypsin digestion and treated with 5 mM sodium salicylate.The expression levels of caspase 3 were detected by real-time PCR and western blot.Results： Compared with control group,sodium salicylate（5 mM） had no effect on caspase 3 mRNA and protein in 1 h（P0.05）.However,a prolonged application of sodium salicylate was given to the SGN,the expression of caspase 3 mRNA and protein were significantly increased（P0.05）.These changes were related to the treatment time of sodium salicylate.Conclusion： Administration of sodium salicylate can increase the expression of caspase3 mRNA and protein,would induce apoptosis.It has some application value to research cochlea toxicity.