摘要
目的观察乌头碱对表达在卵母细胞上的hKv1.5电流的影响。方法 hKv1.5通道表达在非洲爪蟾卵母细胞上,利用双电极电压钳技术测量其电流。结果①hKv1.5通道可以稳定表达在卵母细胞上;②乌头碱以浓度和电压依赖性方式阻断表达在卵母细胞上的hKv1.5通道,阻断的IC50值是0.796±0.123μmol/L,其Hill系数为0.280±0.020;③乌头碱对hKv1.5电流的阻断呈时间和频率依赖性。结论乌头碱对hKv1.5电流呈浓度、电压和时间依赖性阻断,提示乌头碱可能是一种开放型钾通道阻断剂,它对开放状态和失活状态下的hKv1.5通道均具有阻断作用。
Objective To investigate the inhibitory action of aconitine on human Kvl. 5 ( hKv1. 5) channels expressed on Xenopus laevis oocytes. Methods hKv1. 5 channels were expressed on Xenopus laevis oocytes and studied using two microelectrode voltage clamp technique. Results HKv1. 5 channels could be stably expressed on Xenopus laevis oocytes. Aconitine produced a voltage- and time-dependent inhibition on hKvl. 5 channels expressed on Xenopus laevis oocytes. Meanwhile, the inhibition on hKvl. 5 channels was concentrition-dependent. The IC50 and Hill coefficient were 0. 796 +0. 123 μmol/L and 0.280 ±0.020 respectively, and this action could be partly reversable . On the other hand, the suppresion action was frequncy-dependent. Conclusions Aconitine blocks hKvl. 5 channel in a voltage-and time-and concentration-and frequncy-dependent fasion, futhermore, it inhibits the channels either in open or in inactive state. So it indicates that aonnitine may be an open state inhibiter of hKv1. 5 potassium channels. [ Chinese Journal of Cardiac Pacing and Electrophysiology, 2010,24 (2) : 167 - 171 ]
出处
《中国心脏起搏与心电生理杂志》
北大核心
2010年第2期167-171,共5页
Chinese Journal of Cardiac Pacing and Electrophysiology
关键词
电生理学
乌头碱
hKv1.5
心律失常
钾通道
电压钳技术
Electrophysiology
Acontine
Human KV1.5
Arrhythmias
Potassium channels
Voltage clamp technique