摘要
目的探讨自由基清除剂依达拉奉对豚鼠耳蜗急性声损伤的保护作用。方法48只白色红目雌性豚鼠随机分为6组。A组（空白对照组）：不做任何处置，单纯检测听功能和耳蜗自由基含量；B组：鼓室注射生理盐水；C组：鼓室注射依达拉奉；D组：单纯噪声暴露；E组：噪声暴露＋静脉注射依达拉奉；F：噪声暴露＋鼓室注射依达拉奉。D、E、F组在声压级125dB的稳态噪声暴露前2d及暴露2h后即刻、2、6、12、24、48和72h检测听功能和耳蜗自由基含量。听功能检测为听性脑干反应（ABR），自由基检测采用电子顺磁共振（electron spin resonance，ESR）技术。比较各组动物在不同时间点ABR阈移及自由基含量的变化。结果急性声损伤后豚鼠ABR阈值明显升高，与空白对照组比较，差异具有统计学意义（P〈0．05），暴露后72h仍未恢复正常。鼓室注射依达拉奉可使阈值下降约10dB，而静脉注射则无此作用。空白对照组豚鼠耳蜗自由基值为21．68（cm／g），急性声损伤后耳蜗自由基含量明显增加，在噪声暴露后2h达峰值，至观察结束时仍未恢复正常。静脉注射依达拉奉组对噪声损伤后耳蜗自由基生成未见明显抑制作用，而鼓室注射组则可明显抑制自由基产生。结论经鼓室局部应用依达拉奉，对豚鼠急性声损伤后的耳蜗听觉功能具有保护作用，其机制可能与有效清除局部自由基有关。
Objective To assess whether the free radical scavenger, edaravone, could provide protection from oxidative stress and hearing loss induced by noise exposure. Methods Forty-eight guinea pigs were divided into six groups and exposured to a stationary noise at 125 dB SPL for 2 h only once. Group A： measured hearing and reactive oxygen species （ROS） level without noise exposure. Group B： intratympanic saline injection. Group C .. intratympanic edaravone injection. Group D ： exposed to noise for 2 h. Group E： intravenous edaravone injection after noise exposure. Group F.. intratympanic edaravone injection after noise exposure. All animals of group D, E and F were measured hearing with ABR before noise exposure, immediately after noise exposure and at 2, 6, 12, 24, 48, 72 b after noise exposure, and then were decapitated for ROS measurement with electron spin resonance technology. Results After noise exposure, the ABR threshold of group D increased immediately after acute acoustic trauma and did not get fight finally, while group F came back about 10 dB SPL. The normal level of ROS in the cochlea of guinea pigs was about 21.68 （cm/g） and significantly increased after acute acoustic trauma, reaching its peak in 2h, and didn＇t return to normal after 72h. Group E did not inhibit free radicals, while group F showed significant effect on inhibiting production of free radicals. Conclusions The level of ROS in cochlea were decreased significantly after intratympanic edaravone injection. The mechanism may due to its effective clearance of the ROS in cochlea.
出处
《中华耳鼻咽喉头颈外科杂志》
CAS
CSCD
北大核心
2009年第2期150-153,共4页
Chinese Journal of Otorhinolaryngology Head and Neck Surgery
基金
基金项目：首都医学发展科研基金（2005-2037）
关键词
听觉丧失
噪声性
自由基清除剂
自由基
豚鼠
Hearing loss, noise-induced
Free radical scavengers
Free radicals
Guinea pigs
