p-ERK5在快速衰老小鼠耳蜗血管纹中的增龄性变化

Extracellular signal regulated kinase 5 (pERK5) in senescence accelerated mice

摘要:

目的探讨快速衰老小鼠耳蜗血管纹中磷酸化的细胞外信号调节激酶5（phosphorylated extracellular signalregulated kinase 5, pERK5）表达的增龄性变化。方法选用3、5、7月龄的快速衰老小鼠亚系８（senescence accelerated mouse, ＳＡＭＰ８）各６只，分别进行８ｋＨｚ短纯音听性脑干反应（ＡＢＲ）检测，并用免疫组化染色方法分别检测各月龄组小鼠耳蜗血管纹细胞中pERK5的表达，分析其增龄性变化。结果3、５、７月龄小鼠耳蜗血管纹细胞中pERK5平均光密度值分别为0.3838±0.0020、0.3646±0.0010、0.3423±0.0036； pERK5在不同月龄快速衰老小鼠耳蜗组织中的表达光密度值随着月龄增加而显著降低（P＜０.０５）。结论随着年龄相关性功能减退，快速衰老小鼠耳蜗血管纹中pERK5的表达水平逐渐降低，推测pERK5可能与维持正常的耳蜗功能及听觉有关。

关键词:快速衰老小鼠|耳蜗血管纹|磷酸化的细胞外信号调节激酶5

Abstract:

ObjectiveTo study degenerative changes of agerelated expression of phosphorylated extracellular signalregulated kinase 5 (pERK5) in the cochlear stria vascularis of rapid aging mouse.Methods18 mice of senescence accelerated mouse subline 8 (SAMP8) with age of 3 months (n=6), 5 months (n=6) and 7 months (n=6) were studied. Auditory brainstem response (ABR) was elicited with 8KHZ short pure tone, expression of pERK5 in the cochlear stria vascularis was detected using immunohistochemical staining, and the agerelated changes were analyzed in all the mice.ResultsThe average optical densities of pERK5 in the cochlear stria vascularis cells in the 3, 5 and 7 months old mice were 0.3838±0.0020, 0.3646±0.0010 and 0.3423±0.0036 respectively. The optical density of pERK5 declined significantly with age (P<0.05).ConclusionsThe expression level of pERK5 in the cochlear stria vascularis of rapid aging mice declines with the agerelated hypofunction. This indicates that pERK5 is probably related to maintenance of cochlea function and auditory function.

Key words:Rapi d aging mouse| Cochlear stria vascularis|Phosphorylated extracellular signalregulated kinase 5