庆大霉素耳中毒后不同时间耳蜗血管纹HSP70表达及ABR关系.doc

庆大霉素耳中毒后不同时间耳蜗血管纹HSP70表达及ABR关系 　【摘要】 观察庆大霉素（GM）耳中毒后不同时间豚鼠耳蜗血管纹热休克蛋白70（HSP70）表达与ABR的关系。方法：选用健康白色红目豚鼠100只，体重200～250g，随机分为：生理盐水组、GM组，各组皆连续用药10d。各组动物混合饲养，每日测量体重调整药量。在用药前和停药后1、3、7、14、30d分别检测ABR阈值，停药处死后应用SABC免疫组化技术，观察GM中毒后不同时间豚鼠耳蜗血管纹HSP70表达情况。结果：GM组停药3d时耳蜗血管纹HSP70阳性反应产物表达最多，ABR阈值最高。以后随着停药时间延长，染色逐渐变浅，ABR阈值逐渐降低，停药30d时染色接近正常，但ABR阈值仍明显高于正常，它们与正常对照组相比差异均有显著意义（P﹤0.01）。结论：耳蜗血管纹HSP70阳性反应产物灰度值与ABR之间呈线性关系，可以作为细胞受到应激刺激后细胞恢复程度的一个指标。 【关键词】 耳毒性 庆大霉素 热休克蛋白 耳蜗 免疫组化 AbstractObjective：To study the relationship of expression of heat shock protein 70(HSP70)in stria vascularis and ABR on gentamicin(GM) ototoxicityinduced in different time of guinea pigs cochlea. Methods : A total of 100 healthy white guinea pigs with red eyes were studied. They were all 200～250g weight and divided into two groups ,GM and saline control. Each group were medicated continuitly for 10 days.The auditory brainstem response (ABR) threshold on the 1st, 3 rd , 7th,14th, 30th day before administration and after discontinuation were detected.Immunohistochemistry staining was used to observe GM ototoxicityinduced expression of HSP70 . Results :The expression of positive production of HSP70 in stria vascularis of cochlea reached the maximum on the 3rd day after discontinuation in GM group, as well as the threshold of ABR . The staining truned to light gradually and the threshold of ABR degraded gradually accompanied with extension of time of discontinuation. The staining approached normol level on the 30th day after discontinuation, but the threshold of ABR was still higher than normol level, and there was significance compared with the control group (P﹤0.01). Conclusion: There was a linear correlation between the average gray of HSP70 in stria vascularis and the ABR thresholds. HSP is also the index of cell resuming after stress stimuli. Ｋｅｙ　ｗｏｒｄｓdrug toxity; gentamicins; heat shock protein;stria vascularis;immunohistochemistry 庆大霉素（gentamicin ，GM）耳中毒后能够诱发耳蜗热休克反应,增加热休克蛋白（heat shock protein, HSP）70 在豚鼠耳蜗的表达, 且ABR 阈值