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.
出处
《吉林大学学报(医学版)》
CAS
CSCD
北大核心
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)
关键词
甲基汞
毛细胞
外向钾电流
膜片钳术
methylmercury
hair cells
outward potassium currents
patch clamp techniques