甲基汞对豚鼠耳蜗外毛细胞外向钾电流的影响  

Effects of methylmercury on outward potassium currents in isolated outer hair cells of guinea pig cochlea

作　　者：刘淑芳[1] 郭晓峰[1] 全成实[2] 

机构地区：[1]吉林大学第一医院耳鼻咽喉-头颈外科,吉林长春130021 [2]吉林大学基础医学院病理学教研室,吉林长春130021

出　　处：《吉林大学学报（医学版）》2006年第4期612-614,共3页Journal of Jilin University：Medicine Edition

基　　金：吉林省科技厅资助课题(990590)

摘　　要：目的:观察甲基汞对豚鼠耳蜗外毛细胞侧膜K+电流的影响,探讨甲基汞耳毒性的离子机制。方法:采用全细胞膜片钳技术分别观察汞污染度为1/1000 LD50、1/100 LD50、1/10 LD50对外毛细胞Ca2+敏感外向IK(Ca)电流的影响。结果:汞中毒后IK(Ca)幅值分别为(1.48±0.28)、(1.36±0.16)和(1.22±0.13)nA,与正常对照组相比分别下降了8%、16%和25%(P<0.05)。结论:甲基汞以浓度依赖方式抑制Ca2+敏感的外向K+电流,使IK(Ca)幅值降低,最后导致听觉机能下降。这可能是甲基汞中毒的耳毒性机制之一。Objective To investigate the effects of methylmercury on outward potassium currents in isolated outer hair cells of guinea pig cochlea. Methods The whole-cell patch clamp technique was used. Calcium sensitive outword potassium currents were recorded when the concentrations of mercurial were 1/1000 LD50, 1/100 LD50 and 1/10 LD50. Results After methylmercury poisoning, amplitudes of the outword potassium currents IK（Ca） were （1.48±0.28）, （1.36±0. 16） and （1.22±0. 13） hA. Compared with control group, the amplitudes in three methylmercury poisoning groups were decreased by 8%, 16% and 25% （P〈0.05）. Conclusion Methylmercury can reduce IK（Ca） in a dose-dependent manner, it may be one of the mechanisms of ototoxicity.

关 键 词：甲基汞 毛细胞 外向钾电流 膜片钳术 

分 类 号：R155.33[医药卫生—营养与食品卫生学] R329.25[医药卫生—公共卫生与预防医学]