摘要
目的 观察慢性次声暴露对豚鼠听阈及耳蜗毛细胞形态学的影响和作用特点 .方法 通过听觉脑干诱发电位测试 (ABR)及扫描电镜分别观察了豚鼠在 8Hz,1 2 5 d B SPL ,1次· d- 1 ,2 h/次的次声暴露条件下 ,其听阈和耳蜗毛细胞听毛形态的变化情况 .结果 豚鼠在 click声及 9个频率的短纯音的听阈均有升高 ,最大阈移为 2 6 d B (4k Hz短纯音 ) ,最小阈移为 1 8d B(click声 ) ;豚鼠听阈的升高缺乏频率选择性 ,各频率阈移间无显著差异 .扫描电镜观察可见耳蜗毛细胞出现了以外毛细胞为主的损伤表现 ,且由底周至顶周外毛细胞听毛的损伤逐渐加重 .结论 慢性次声暴露确可使豚鼠听力出现下降 ,但与白噪声相比其又有自己的声损伤特点 ,可能在声损伤机制上二者是有差别的 .
AIM To explore the effects of infrasound on auditory threshold and morphology of cochlear hair cells in guinea pigs. METHODS The guinea pigs were exposed to infrasound with 8 Hz, 125 dB SPL, 2 h/time, 1 time/d for 30 days. and the changes of auditory threshold and morphology of cochlear hair cells were observed by auditory brainstem response audiometry (ABR) and scanning electron microscopy (SEM). RESULTS The increase of ABR auditory threshold could be seen in all nine frequencies of toneburst and click sound. The maximum change was 26 dB (4 kHz to neburst) and the minimum change was 18 dB (click sound). There was no difference between the changes of ABR auditory threshold in all frequencies of toneburst and click sound. By scanning electron microscopy, some injury was observed in outer hair cells (OHCs) of cochlea. The most serious injury was found in the fourth turn of basilar membrane, then the third, and the second in the order of decreasing severity. The basal turn was almost normal. CONCLUSION The hearing of guinea pigs can be injured by exposing to infrasound. But there is difference between infrasound and white noise in their way of causing hearing injury.
出处
《第四军医大学学报》
2000年第1期9-12,共4页
Journal of the Fourth Military Medical University
基金
全军重点指令性课题基金!( 96Z0 42 )
关键词
次声
听阈
毛细胞
豚鼠
耳蜗
infrasound
auditory threshold
hair cell
guinea pigs
