CAJ | 학술논문

目的研究苄基四氢巴马汀(BTHP)对心室肌细胞快激活(Ikr)延迟整流钾电流的作用.方法用全细胞膜片钳技术记录豚鼠心室肌细胞钾离子通道电流.结果 BTHP在1～100 μmol*L-1以浓度依赖性方式阻滞Ikr,其IC50为13.5 μmol*L-1(95%可信范围:11.2～15.8 μmol*L-1).30 μmol*L-1 BTHP可使Ikr及Ikr,tail分别降低(31±4)%和(36±5)% (n=6,P<0.01).与多数III类抗心律失常药物不同,BTHP可频率依赖性地抑制Ikr.该药主要改变Ikr的失活过程,可使Ikr的失活时间常数(τ)从(238±16) ms降至(196±14) ms,而对Ikr的激活动力学影响不大.结论 BTHP对Ikr有明显的抑制作用,且其阻滞作用呈现频率依赖性特征.
목적연구변기사경파마정(BTHP)대심실기세포쾌격활(Ikr)연지정류갑전류적작용.방법용전세포막편겸기술기록돈서심실기세포갑리자통도전류.결과 BTHP재1～100 μmol*L-1이농도의뢰성방식조체Ikr,기IC50위13.5 μmol*L-1(95%가신범위:11.2～15.8 μmol*L-1).30 μmol*L-1 BTHP가사Ikr급Ikr,tail분별강저(31±4)%화(36±5)% (n=6,P<0.01).여다수III류항심률실상약물불동,BTHP가빈솔의뢰성지억제Ikr.해약주요개변Ikr적실활과정,가사Ikr적실활시간상수(τ)종(238±16) ms강지(196±14) ms,이대Ikr적격활동역학영향불대.결론 BTHP대Ikr유명현적억제작용,차기조체작용정현빈솔의뢰성특정.
AIM To investigate the effect of benzyltetrahydropalmatine (BTHP) on the rapidly activating component of delayed rectifier K+ current (Ikr) in single guinea pig ventricular myocytes. METHODS Whole-cell patch clamp technique was used to record Ikr. RESULTS Ikr was blocked by 1～100 μmol*L-1 BTHP in concentration-, voltage-, and specifically frequency-dependent fashion, with IC50 of 13.5 μmol*L-1 (95% confidence range: 11.2～15.8 μmol*L-1). 30 μmol*L-1 BTHP reduced Ikr and Ikr,tail by (31±4)% and (36±5)% (n=6, P<0.01), respectively. The time constant for deactivation (τ′) of the tail current was decreased by 30 μmol*L-1 BTHP from (238±16) ms to (196±14) ms, while drug had no any effect on the time constant for activation (τ) of Ikr,tail. CONCLUSION BTHP inhibited Ikr in a frequency-dependent fashion.