【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。更多还原

【Abstract】 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 I_K（Ca） were（1.48±0.28）,（1.36±0.16） and（1.22±0.13）nA.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 I_K（Ca） in a dose-dependent manner,it may be one of the mechanisms of ototoxicity.更多还原