【摘要】 目的探讨快速老化小鼠听觉功能、以及耳蜗组织中甲基化结合蛋白-2(methyl-CpG-bindingprotein2,MeCP2)的增龄性变化。方法本研究选3、5、7、9月龄的快速老化小鼠亚系1(Senescence acceler-ated mouse/prone1,SAMP 1)作为实验组,而同龄抗快速老化亚系1(Senescence accelerated mouse/resistance 1,SAMR 1)作为SAMP 1的正常对照组。应用听觉诱发反应仪检测其听觉脑干反应阈值;应用RT-PCR和Western印迹杂交对耳蜗组织中MeCP2mRNA和蛋白的表达水平进行半定量分析。结果第7、9月龄SAMP1脑干反应阈值较同龄SAMR1明显增高(P<0.05);MeCP2 mRNA和蛋白在不同月龄快速老化小鼠耳蜗组织中均有表达,第7、9月龄SAMP1小鼠耳蜗组织中的MeCP2 mRNA和蛋白较同龄SAMR1小鼠明显降低(P<0.05)。结论MeCP2 mRNA和蛋白的表达水平随着快速老化小鼠听觉功能增龄性减退而降低,说明MeCP2可能与维持耳蜗的功能状态有关。更多还原

【Abstract】 [Objective]The purpose of this study was to analyze age-related hearing loss in the senescence ac-celerated mouse and the expression of MeCP2 gene at mRNA and protein in the cochlea of the senescence acceler-ated mouse throughout development. [Methods]We chose the 3, 5, 7, 9th month as analyzing time points. The au-ditory thresholds and the expression of MeCP2 gene at mRNA and protein in the cochlea were studied in the senes-cence accelerated mouse/prone 1 (SAMP 1) at 3, 5, 7, 9 months. Normal aging control the senescence accelerated mouse/resistance 1 (SAMR 1) was used. The expression of MeCP2 gene at mRNA level was analyzed by RT-PCR. The expression of MeCP2 protein was analyzed by Western blot. [Results]Auditory function evaluation: Compared with the SAMR 1, the SAMP 1 at 7, 9 months developed a progressive hearing loss at 8 kHz,which showed an age-related significant increase (P <0.05). The expression of MeCP2 mRNA and MeCP2 protein in the cochlea: there were MeCP2 mRNA and MeCP2 protein expressed in the cochlea of the senescence accelerated mouse throughout the development. Compared with the SAMR 1, the SAMP 1 at 7, 9 months developed a significant descend (P < 0.05). [Conclusion]The expression level of MeCP2 mRNA and MeCP2 protein decreases when the senescence ac-celerated mouse develop a progressive hearing loss. This indicates that MeCP2 protein probably has relationship with maintaining functional status of the cochlea.更多还原