Fujimura K, Yoshida M, Makishima K
Department of Otorhinolaryngology, University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan.
Acta Otolaryngol. 2001 Oct;121(7):781-6. doi: 10.1080/00016480152602203.
The effects of salicylate and acoustic overstimulation on the electromotility of the cochlear outer hair cells (OHCs) were assessed in vivo using electrically-evoked otoacoustic emissions (EEOAEs). Alternating currents to evoke the EEOAE were delivered by means of an extracochlear electrode on the round window, with which the compound action potentials (CAPs) were also monitored before and after the manipulations. The EEOAE outputs were a linear function of the injected currents between 52 and 267 microA rms. Administration of salicylate (500 mg/kg) reduced the EEOAE outputs significantly at 5 and 8 kHz (p < 0.005). while no change in EEOAEs was observed at any frequency after exposure to a 4 kHz pure tone at 100 dB SPL for 10 min or at 120 dB SPL, for 30 min. These results indicate that administration of salicylate reduces the electromotility of the OHCs, and thus produces losses in neural sensitivity of the cochlea. In contrast, the electromotility of OHCs appears to be protected against short-term intense sound exposure.
采用电诱发耳声发射（EEOAE）在体内评估水杨酸盐和声学过度刺激对耳蜗外毛细胞（OHC）电运动的影响。通过圆窗上的耳蜗外电极施加用于诱发EEOAE的交流电，在操作前后还利用该电极监测复合动作电位（CAP）。EEOAE输出是52至267微安均方根值之间注入电流的线性函数。给予水杨酸盐（500毫克/千克）后，在5千赫和8千赫时EEOAE输出显著降低（p < 0.005）。而在暴露于100分贝声压级的4千赫纯音10分钟或120分贝声压级30分钟后，在任何频率下均未观察到EEOAE有变化。这些结果表明，给予水杨酸盐会降低OHC的电运动，从而导致耳蜗神经敏感性丧失。相比之下，OHC的电运动似乎能免受短期强声暴露的影响。
