条件化噪声对强噪声所致豚鼠听力损伤的防护作用

Protective effect of conditioning noise on high intensity noise induced hearing loss in guinea pigs

目的 观察低强度实际工作环境噪声对相应的高强度噪声所致听力损伤是否有防护作用。方法 取杂色,耳廓反射正常,鼓膜完整的豚鼠30只,分为三组:条件化噪声组(CG),高强度噪声暴露组(HG),条件化噪声加高强度噪声暴露组(CHG)。所用低强度噪声(条件化噪声)为80dBSPL,高强度噪声为115dBSPL。每组动物实验前后进行听性脑干反应(ABR)测试,记录其反应阈。结果 给予条件化噪声暴露后,豚鼠的ABR反应阈与实验前相比无变化,而高强度噪声暴露和先条件化噪声再高强度噪声暴露后豚鼠的ABR反应阈均增高,但前者比后者的反应阈明显增高(P<0.001)。结论 低强度实际工作环境噪声对相应的高强度噪声所致豚鼠听力损伤具有一定防护作用。

Objective To observe the protective effect of low intensity noise (conditioning noise ) on high intensity noise induced hearing loss in guinea pigs.Methods Thirty healthy guinea pigs with normal preyer's reflex were used . The animals were divided into three groups, the conditioning noise group(CG), the high intensity noise group(HG) and the conditioning noise plus high intensity noise group(CHG).The intensity of conditioning noise and intensity of high intensity noise were 80 dB SPL and 115dB SPL respectively. The thresholds of ABR of the animals were recorded before and after experiment.Results The ABR thresholds of the animals had no change after exposure to conditioning noise. The ABR thresholds increased significantly after experiment in HG and CHG. The ABR thresholds of the HG animals after experiment were significantly higher than that of CHG animals (P< 0.001 ).Conclusion The low intensity noise had some protective effect on high intensity noise induced hearing loss in guinea pigs.