隐性听力损失动物模型建立与防护的研究

An Animal Model and Protection of Hidden Hearing Loss

目的通过脉冲噪声分别对豚鼠进行30、15次的暴露,分析比较豚鼠的听力学变化,探索建立隐性听力损失模型的适合条件。同时给予氢气,探究其对隐性听力损失的预防作用。方法选取ABR听阈正常的豚鼠16只,随机分为4组:空白对照组、脉冲噪声30次组、脉冲噪声15次组、氢气吸入+脉冲噪声15次组。脉冲噪声压力峰值为163 dB SPL,脉宽为0.25ms,间隔时间为6.5s。分别于脉冲噪声暴露前及暴露后24h进行听性脑干反应测定。结果通过统计学分析发现,豚鼠在30次脉冲噪声暴露24h后,其ABR短声阈值及短纯音(16 kHz 70 dB SPL)Ⅰ波幅值产生明显改变,具有统计学意义;15次脉冲噪声暴露组豚鼠其各项听力学指标都发生显著改变;氢气预处理组同单纯脉冲噪声暴露15次组的暴露24h后听力学指标相比,其ABR短声阈值及短纯音(16 kHz 70 dB SPL)Ⅰ波幅值存在统计学差异。结论本研究中脉冲噪声暴露30次及15次均对豚鼠听力产生显著影响。其中脉冲噪声暴露15次的豚鼠,其各项听力学指标都符合隐性听力损失的听力学特点,脉冲噪声暴露15次是建立隐性听力损失动物模型的可行条件。此外,氢气防护组较单纯脉冲噪声暴露组,听力学指标存在显著差别,表明氢气对隐性听力损失具有预防作用,为进一步的分子机制研究提供直接实验依据。

To determine a suitable condition for an animal model of hidden hearing loss using impulse noise and the preventive effect of hydrogen on hidden hearing loss.Methods Sixteen guinea pigs with normal auditory brainstem response(ABR)thresholds were randomly divided into 4 groups to receive 30 doses of impulse noise exposure(163 dB SPL peak-to-peak,pulse width=0.25 ms,interval=6.5s),15 doses of impulse noise exposure,15 doses of impulse noise exposure plus hydrogen treatment or serve as controls.The ABR was measured before and 24h after the impulse noise exposure.Results Compared with controls,at 24 hours post-exposure,there was a significant change in ABR thresholds as well as in wave I amplitudes of 16 kHz tone burst(70 dB SPL)induced responses in 30 doses groups,while all auditory indicators in the 15 doses group demonstrated significant changes.In addition,ABR thresholds and wave I amplitudes of 16 kHz tone burst(70 dB SPL)induced responses in hydrogen treated animals were sig-nificantly different from the 15 doses group without hydrogen treatment.Conclusions Impulse noise exposure in this study(30 or 15 doses)demonstrated significant effects on hearing,with 15 doses exposure resulting in auditory characteristics of hidden hearing loss,indicating a suitable condition for an animal model of hidden hearing loss.In addition,hydrogen appeared to protect against the 15 doses exposure,indicating a potential preventive effect on hidden hearing loss.Our results provide an experimental basis for further molecular mechanism research.