摘要
目的探讨雌激素对暴露于风洞噪声小鼠听觉电生理及耳蜗形态学改变的影响,为噪声性耳聋的预防提供依据。方法 60只小鼠随机分为A、B、C三组,每组20只,三组小鼠分别暴露于风洞模拟噪声环境中,每天8小时,连续7天。B组于暴露噪声前30min肌肉注射苯甲酸雌二醇0.15mg/只,C组暴露噪声结束后30min肌肉注射苯甲酸雌二醇0.15mg/只。分别于实验前、接噪3天、接噪7天、脱噪恢复3天、脱噪恢复7天后测试各组小鼠脑干诱发电位(ABR)阈值,取耳蜗标本行扫描电镜检查。结果三组小鼠在接噪3天、接噪7天的ABR阈值均比实验前增高,但组间无明显差异。三组小鼠在脱噪恢复3天、脱噪恢复7天ABR阈值均比接噪7天有恢复,但雌激素治疗组较其余两组恢复效果明显。扫描电镜显示单纯噪声组损伤最重,雌激素预防组损伤次之,雌激素治疗组损伤最轻。结论风洞噪声能造成小鼠听觉电生理及耳蜗形态学的改变;雌激素对小鼠风洞噪声性耳聋有保护作用;雌激素治疗组保护效果较雌激素预防组明显。
Objective To investigate potential protective effects of estrogen against hearing damage in mice exposed to wind tunnel noise. Methods Sixty mice were randomly divided into three groups （A, B and C, 20 each） and exposed to wind tunnel noise 8 hours per day for 7 consecutive days. Animals in Group B received intramuscular injection of 0.15 mg estradiol benzoate 30 ruin before noise exposure, and those in Group C received the same treatment but at 30 rain after the exposure. Animals in Group A received no treatment. Auditory brainstem response （ABR） thresholds were obtained before noise exposure, on Days 3 and 7 during the exposure, and on Days 3 and 7 after the exposure. The cochlea was also harvested for scanning electron microscope （SEM） study at each time point. Results ABR thresholds were elevated along with noise exposure in all groups. ABR thresholds showed recovery on Days 3 and 7 post-exposure, but the recovery was greater in Group C than in Groups A and B. SEM examination showed the most severe cochlear damage in Group A, followed by group B, and the least amount of damage in Group C. Conclusion Wind tunnel noise causes cochlear damage with hearing threshold elevation in mice. Estrogen appears to protect against this damage. The protective effectsappear to be greater when estrogen is administered as a treatment after noise exposure than when prophylactically given before noise exposure.
出处
《中华耳科学杂志》
CSCD
2011年第3期323-326,共4页
Chinese Journal of Otology
基金
全军十一五医药卫生科技攻关科研项目(项目号:08G059)
关键词
风洞噪声
听性脑干反应
雌激素
扫描电镜
保护
Wind tunnel noise
Auditory brainstem response
Estrogen
Scanning electron microscope
