摘要
采用膜片钳技术,研究了莲心碱(Liensinine,Lien)对大鼠心室肌细胞动作电位及钠电流(INa)、L-型钙电流(ICa-L)及稳态外向K+电流的影响,Lien30μmol/L可显著地降低动作电位幅度、静息膜电位,延长动作电位时程。Lien10,30μmol/L分别使INa及ICa-L从给药前的(7.9±2.2)nA和(699±175)pA降至(4.3±1.7)、(1.8±1.6)nA和(203±132)、(147±121)pA。Lien10μmol/L还抑制INa、稳态外向K+电流和ICa-L的I-V曲线并使后者的峰值电流电位略右移。提示Lien有钠、L型钙通道阻滞作用并抑制稳态外向K+电流,这些可解释Lien广泛的抗心律失常作用机制。
Effects of Liensinine (Lien) on the action potentials, sodium channel current (INa), L-type calcium channel current (ICa-L) and steady-state outward K+ current of rat ventricular myocytes were studied by use of the whole cell recording patch clamp technique. Lien 30μmol/L could significantly reduce the action potential amplitude, resting potential and prolong the action potential duration. Lien (10 or 30μmol/L) decreased INa and ICa-L respectively from (7. 9 ± 2. 2) nA and (699± 175) pA as control level to (4. 3± 1. 7), (1. 8±1. 6 ) nA and (203±132), (147±121 ) pA. Also, Lien 10 μmol/L could inhibit the I-V curves of INa, steadystate outward K+ currents and ICa-L and slightly shift the maximum current potential of the latter to the right.The results suggested Lien has blocking actions on sodium and calcium channels and could inhibit steady-state outward K+ currents, which can explain the mechanism of extensive antiarrhythmic actions of Lien.
出处
《同济医科大学学报》
CSCD
1999年第6期496-499,共4页
Acta Universitatis Medicinae Tongji
基金
国家自然科学基金!39370795
关键词
莲心碱
心室肌细胞
膜片钳技术
L-型钙电流
钠电流
Liensinine
ventricular myocyte
whole cell recording patch clamp
sodium channel current
L-type calcium channel current