水杨酸钠影响耳蜗螺旋神经节神经元GABAa受体亚单位的表达

The effect of sodium salicylate on the expression of GABAa receptor subunits in cochlear spiral ganglion neurons

目的:观察大鼠耳蜗螺旋神经节神经元(SGN)中GABAa受体亚单位的基因表达水平,探讨水杨酸钠对SGN的GABAa受体亚单位表达的影响。方法:应用实时荧光定量PCR技术,检测新生SD大鼠SGN和大脑皮层GABAa受体12个亚单位的表达;观察水杨酸钠5mmol/L处理15min、30min、1h、3h和6h后的不同时间段原代培养SGN的GABAa受体亚单位的表达。结果:1SGN有GABAa受体α1-6、β1-3、γ1-3亚单位的表达,各亚单位的表达量均低于大脑皮层(P<0.05)。在SGN的α亚单位族中,表达量:α2>α3/α5>α4>α1>α6,α3和α5表达量差异无统计学意义(P>0.05);β亚单位族表达量:β3>β2>β;γ亚单位族表达量:γ1>γ2>γ3。2水杨酸钠作用后,除α5外,各时间点亚单位表达量都有明显变化。其中15min时α1、α2、β1、γ1-3表达量升高,而α3表达量降低(P<0.05);30min时,α3、β1、β3表达量升高,而γ1表达量降低(P<0.05);1h时,β2表达量升高而γ3表达降低(P<0.05);3h时,β1、β2表达量升高,而α3、γ2表达量降低(P<0.05);6h时,α1、α3、β2、β3、γ1表达量升高,而α2、α4、β1表达量降低(P<0.05)。结论:大鼠SGN上有GABAa受体α1-6、β1-3、γ1-3的表达,其亚单位的表达量均低于大脑皮层。水杨酸钠可导致SGN的GABAa受体亚单位表达量改变,在最早期(15min)时,大部分亚单位表达为明显升高,其后在正常值上下低水平波动。

Abstract Objective：To investigate mRNA expression of GABAa receptor（GABAaR） subunits in the rat co- chlear spiral ganglion neurons （SGN） and explore the effect of sodium salicylate （SS） on the expression of GABAaR subunits. Method：The realtime fluorescent quantitative PCR （FQ-PCR） was used to detect mRNA expression of twelve GABAaR subunits in the newborn rat SGN and then investigate mRNA expression of GABAaR subunits alter treatment with 5 mmol/L SS for 15 min, 30 min, 1 h, 3 h and 6 h in the primary culture SGN. Resuit：①GABAaR subunits of α1-6、β1-3、γ1-3, and 713 were detected in the SGN, and the expression of GABAaR subunits was lower than those in the cerebral cortex. In the subunit α family of GABAaR, the expression rank was α2〉α3/α5〉α4〉α1〉α6,and the expression of aa and as had no difference （P〉0. 05）, In the sulaunit β family, the expression rank was β3〉β2〉β1.In the subunit γ family, the expression rank was γ1〉γ2〉γ3.②The expression of all subunits of GABAa receptor was obviously fluctuated excepting subunit a5 after treatment with SS. At 15 min post-SS, a1, a2, 61 and β1 a were upregulated, and aa was downregulated; At 30 rain post-SS, a3 , β1 and β3 were upregulated, and β1 was downregulated; At 1 h post-SS, 92 was upregulated and β2 was downregulated; At 3 h post-SS, β1 and β2 were upregulated, and β1 and β2 were downregulated; At 6 h post-SS, al, a3,62, β3 and γ1 were upregulated, and a1, a2 and β1 were downregulated. Conclusion：The mRNA of GABAaR was expressed in the rat SGN, and the expression of GABAaR subunits was lower in SGN than the cerebral cortex. SS could alter the GABAaR expression quantity in rat SGN; Most of the subunits expression were elevated obviously in the early post SS （15 rain）, followed by a slight fluctuation.