经圆窗应用地塞米松对豚鼠庆大霉素耳毒性的拮抗作用  

Protection Against Gentamicin Ototoxicity by the Administration of Dexamethasone on the Cochlear Round Window Membrane

作　　者：张慧平[1,2] 李荧[1,3] 王建锋[1] 苏纪平[1] 

机构地区：[1]广西医科大学第一附属医院耳鼻咽喉头颈外科,南宁530021 [2]河北省人民医院耳鼻咽喉科 [3]广州经济开发区医院

出　　处：《听力学及言语疾病杂志》2013年第6期608-611,共4页Journal of Audiology and Speech Pathology

基　　金：广西壮族自治区教育厅科研项目基金(桂教科研[2003]22号)资助

摘　　要：目的探讨经圆窗局部应用地塞米松和全身应用地塞米松对庆大霉素致聋豚鼠耳蜗损害的拮抗作用。方法选用听力正常豚鼠60只,随机分为4组:①庆大霉素组,肌肉注射庆大霉素120mg·kg-1·d-1,1次/天,共10天;②全身用药组,肌肉注射庆大霉素(用法同庆大霉素组),同时腹腔注射地塞米松2.5mg·kg-1·d-1,1次/天,共10天;③局部用药组,肌肉注射庆大霉素(用法同庆大霉素组),右耳经圆窗局部用明胶海绵浸地塞米松(5mg/ml)约0.1ml,共1次。④对照组:肌肉注射与庆大霉素等体积的生理盐水,1次/天,共10天,右耳经圆窗局部用地塞米松1次。于实验前、停药后第1天和第10天分别检测各组动物的听性脑干反应(ABR),显微镜下观察中耳粘膜反应,扫描电镜观察耳蜗毛细胞的形态学变化。结果停药第10天,除对照组外,庆大霉素组、全身用药组、局部用药组动物ABR反应阈较实验前均有不同程度的升高,其中庆大霉素组的反应阈明显高于局部用药组(P<0.05)。扫描电镜下可见庆大霉素组动物耳蜗毛细胞损害严重,而全身和局部用药组动物耳蜗毛细胞损伤程度明显减轻;各组动物中耳粘膜正常。结论地塞米松可以在一定程度上减轻庆大霉素所致的耳毒性,经圆窗局部给药的效果优于全身应用。Objective To investigate the protective effects of round window membrane administration of dex- amethasone（Dex） on ototoxicity induced by gentamicin（GM）. Methods Sixty guinea pigs with normal hearing were randomly divided into four groups, ①GM group： treated with gentamicin by 120 mg · kg^- 1 · d ^-1 for 10 days; ② GM--S--Dex group. treated as the GM group and dexamethasone by intraperitoneal injection 2.5 mg · kg^- 1 · d ^-1 for 10 days; ③GM--T--Dex group： treated as the GM group and dexamethasone by round window administration on right ear; ④NS--T--Dex group： treated with sodium chloride by 120 mg · kg^- 1 · d ^-1 for 10 days and with dex- amethasone topically as GM--T--Dex group. The auditory brainstem response （ABR） was respectively measured before the treatment and on day 1, day 10 after the treatment. After the treatment, animals were killed instantly and the middle ear mucosa and the Corti＇s organ were observed with SEM. Results There was no change of ABR threshold in NS--T--Dex group on day 10 after the treatment, whereas ABR thresholds in the other groups were elevated and GM group was the most significant. The massive outer hair cells loss was observed in GM group while the loss in GM--T--Dex group and GM--S--Dex group was trivial. The middle ear mucosa was normal and no inflammation was found in any of the groups. Conclusion The results indicated that round window administration of dexamethasone had protective effects aganist the gentamicin--induced hearing loss.

关 键 词：地塞米松 庆大霉素 耳毒性 圆窗膜 听性脑干反应 

分 类 号：R764.5[医药卫生—耳鼻咽喉科]