噪声刺激对大鼠ABR反应阈值及耳蜗细胞凋亡的影响

Effects of noise stimulation on ABR response threshold and cochlear cell apoptosis in rats

目的:探讨噪声刺激对大鼠ABR反应阈值及耳蜗细胞调亡的影响。方法:清洁级雄性SD大鼠40只随机分为对照组和实验组各20只(40只耳)。实验组大鼠暴露于4 kHz,120 dB噪声中120 min,制作噪声性听觉损失大鼠模型,对照组不进行处理。分别于噪声暴露前,暴露后1 d,4 d,7 d和14 d检测实验组与对照组大鼠听性脑干反应(ABR)阈值有无差异;同时分别于暴露后上述各时间点处死大鼠免疫组织化学SP法检测耳蜗TUNE阳性表达情况。结果:暴露后第一天开始,实验组ABR反应阈显著高于对照组,且均有统计学差异(P<0.05)。随着时间的延长,ABR反应阈值开始降低;从暴露后第一天开始,实验组TUNE阳性细胞数量显著高于对照组,且均有统计学差异(P<0.05)。结论:噪声暴露明显提高了大鼠ABR反应阈,且耳蜗细胞凋亡增进,可能与噪声性耳聋发病机制有关。

Objective To investigate the effects of noise stimulation on ABR response threshold and cochlear cell apoptosis in rats.Method 40 male SD rats were randomly divided into the control group and the experimental group,with 20 rats in each group(40 ears).Rats in the experimental group were exposed to 4 kHz and 120 dB noise for 120 min.Noise induced hearing loss rat model was produced,while the control group did not deal with it.Before exposure,1 days,4 days,7 days and 14 days after exposure,there was no difference in auditory brainstem response(ABR) threshold between the experimental group and the control group.At the same time,the positive expression of TUNE in the cochlea was detected by the immunohistochemistry SP method.Results After the first day of exposure,the ABR response threshold of the experimental group was significantly higher than that of the control group,and there was a statistically significant difference(P<0.05).With the prolongation of time,the ABR reaction threshold began to decrease.From the first day after exposure,the number of TUNE positive cells in the experimental group was significantly higher than that in the control group,and there were statistically significant differences(P<0.05). Conclusion Noise exposure significantly increased the ABR response threshold in rats and increased the apoptosis of cochlea cells,which may be related to the pathogenesis of noise induced hearing loss.