Objective To study characteristics of hearing loss in C57BL/6J mice after being exposed to a moderate level noise. Methods Male C57BL/6J mice with normal hearing at age of 5-6 weeks were chosen for this study. The mice were ran-domly selected to be tested immediately after exposure (P0), or 1 day (P1), 3 days (P3), 7 days (P7) or 14 days (P14) after expo-sure. Post-exposure hearing was compared to before exposure. Mice were exposed to a white noise of 100 dB SPL for 2 hrs. ABR thresholds were used to estimate hearing status at each time point. Results Maximal ABR threshold elevations compared to before exposure were seen at P0 at every frequency (P<0.01), more so at high-frequencies (16 kHz and 32 kHz) than lower frequencies (4 kHz and 8 kHz) ( P<0.05 ). From P1 to P14, ABR thresholds were found to decrease progressively, and showed no significant differences from before exposure on P14 (P>0.05). Conclusions There is a frequency specific response to 100 dB SPL white noise exposure in C57BL/6J mice. High-frequency is more susceptible to the exposure. Also, the hearing loss in-duced by this moderate level noise exposure is reversible in C57BL/6J mice.%目的：通过100dB SPL宽频带白噪声对成年C57小鼠进行单次2小时的暴露，观察该种噪声对小鼠听功能损害的特点。方法选取5~6周龄ABR听阈正常的C57小鼠（每组5-7只），随机分为5个实验组分别为：噪声暴露后即刻（P0）、1天（P1）、3天（P3）、7天（P7）、14天（P14）。实验组小鼠于100dB SPL宽频带白噪声环境下暴露2h，本实验采用噪声暴露前的小鼠作为对照组。每只实验小鼠分别于噪声暴露前及暴露后各时间点进行ABR阈值检测以评估听力受损情况，实验采用统计噪声暴露前、后各时间点小鼠ABR差值（阈移）的方法分析实验结果。结果噪声暴露后即刻，小鼠各频率的ABR阈移均为最大值（P<0.01）：Click（11.92±7.51dB）、4kHz（11.92±5.60dB）、8kHz（12.31±5.99dB）、16kHz （21.54±8.75dB）、32kHz（20.00±8.90dB），且在各个频率的阈移中，以16kHz及32kHz处的高频听力损失最严重，明显高于Click、4kHz及8kHz处的阈移（P<0.05）。脱离噪声环境24小时后各频率的ABR阈移开始下降，2周以后，小鼠各频率ABR阈值均完全恢复至暴露前水平（P>0.05）：Click（1.11±6.01dB）、4kHz（1.11±3.33dB）、8kHz（1.11±4.17dB）、16kHz （1.67±4.33）、32kHz（2.78±4.41）。结论100dB SPL宽频带白噪声单次有限暴露可以造成小鼠出现一定程度的听力损害。在频率分布上，高频区域的听力损害更为明显。同时，本研究表明，这种噪声下小鼠听力损害可以表现自我主动恢复的特征。
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