中文摘要：

目的观察卡那霉素对乙酰胆碱升高外毛细胞内Ca^2＋浓度的影响，探讨卡那霉素耳毒性与耳蜗传出神经系统的关系。方法健康豚鼠15只断头处死，人工外淋巴液中分离活性良好的单离外毛细胞（OHC），分为空白对照组、乙酰胆碱（ACh）组和卡那霉素＋ACh组。Fluo-3／AM负载30min，观察OHC内Ca^2＋荧光强度变化，即Ca^2＋浓度的变化。结果空白对照组OHC内Ca^2＋荧光强度基本不变。ACh组OHC内Ca^2＋荧光强度峰值平均升幅底部为3．06倍，顶部为1．61倍（n=6）。卡那霉素＋ACh组OHC内Ca^2＋荧光强度峰值平均升幅底部为1．75倍，顶部为1．29倍（n=6）。结论卡那霉素能够明显抑制ACh引起的外毛细胞内Ca^2＋浓度升高的幅度。

英文摘要：

Aim To observe the effect of kanamycin on the change of Ca^2＋ concentration in outer hair cells caused by acetylcholine to explore the relationship between kanamycin ototoxicity and the cochlear efferent nervous system. Methods After the guinea pigs were killed by decapitation, the OHCs were isolated in artificial perilymph and divided into three groups： control group, acetylcholine （ACh） group and kanamycin ＋ ACh group. OHCs were loaded with Fluo-3/AM for 30 min and then the change of Ca^2＋ fluorescence intensity was observed. Results Ca^2＋ fluorescent intensity in OHCs remained basically unchanged in control group, increased 3.06 times （ n = 6） in ACh Group, and increased 1.75 times （n =6） in kanamycin ＋ ACh Group. Condusions Kanamycin can obviously inhibit the increasing of Ca^2＋ concentration in OHCs caused by ACh.