调脉饮颗粒抗心律失常的多种离子通道靶点作用研究

Study on the anti-arrhythmia effects of Tiaomaiyin granules on various ion channel targets

目的通过研究调脉饮颗粒对心肌细胞动作电位和多种心肌离子通道的作用,探讨调脉饮颗粒抗心律失常的作用靶点。方法采用全细胞膜片钳技术检测0.1 mg/mL和1 mg/mL调脉饮颗粒对重组表达的人源性心脏离子通道靶点快速延迟整流钾通道(rapidly activating delayed rectifier potassuim channel,Ikr,hERG)、钠通道1.5亚型(sodium channel subtype 1.5,NaV1.5)、钙通道1.2亚型(calcium channel subtype 1.2,L-type,CaV1.2)、慢激活延迟整流钾通道(slowly activating delayed rectifier potassuim channel,IKs,KV7.1)、超快延迟整流钾通道(ultra-rapid delayed rectifier potassium channel,IKur,KV1.5)、瞬时外向钾通道(transient outward potassium channel,Ito,KV4.3)、内向整流钾通道(inward rectifier potassium channel,Kir2.1)、ATP敏感性钾通道(ATP sensitive potassium channel,KATP)、钙通道3.2亚型(calcium channel subtype 3.2,T-type,Cav3.2)、乙酰胆碱敏感性钾通道(acetylcholine-sensitive potassium channel, KAch)、超极化激活的阳离子电流亚型2(hyperpolarization-activated cyclic nucleotide-gated ion channel subtype 2,HCN2)和HCN4以及多能干细胞诱导分化心肌细胞(induced pluripotent stem cell dericed cardiomyocyte,IPSC-CM)动作电位和心脏钠钙交换电流(Na+-Ca2+-exchanger,NCX)的作用。结果 0.1 mg/mL调脉饮颗粒显著抑制CaV3.2(18.94%±2.19%)和NCX(28.46%±9.74%)电流,1 mg/mL调脉饮颗粒显著抑制hERG(43.29%±0.09%),CaV3.2(34.72%±0.61%),KATP(38.44%±2.67%),HCN4(30.64%±1.94%)和NCX(64.25%±25.29%)电流,并显著增加KV7.1(34.49%±4.53%)电流(P<0.05);同时调脉饮颗粒可以引起IPSC-CM动作电位时程延长,延长心脏的有效不应期。结论调脉饮颗粒延长IPSC-CM动作电位时程和对NCX、hERG通道电流的抑制作用可能是其抗心律失常作用的主要机制,抑制CaV3.2钙电流和HCN4窦房结起搏电流,可能起到降低心率的作用,增强KV7.1电流可能抵消抑制hERG通道引起的过度的动作电位时程延长和QT间期延长,其对KATP的抑制作用可能起到心肌缺血的保护作用。

Objective In order to investigate the effect of Tiaomaiyin granules on action potential of myocardial cells and multiple ion channels of cardiac muscle.To explore the effect targets of Tiaomaiyin granules playing an anti-arrhythmia role.Method The whole-cell patch-clamp technique was used to detect the effects of 0.1 mg/mL and 1 mg/mL Tiaomaiyin granules on human cardiac ion channel targets of recombinant expression,the channels involved are as follows:rapidly activating delayed rectifier potassuim channel(Ikr,hERG),sodium channel subtype 1.5(NaVl.5),calcium channel subtype 1.2(L-type,CaV1.2),slowly activating delayed rectifier potassuim channel(KV7.1,IKs),ultra-rapid delayed rectifier potassium channel(Kur,KV1.5),transient outward potassium channel(Ito,KV4.3),inward rectifier potassium channel(Kir2.1),ATP sensitive potassium channel(KATP),calcium channel subtype 3.2(T-type,Cav3.2),acetylc holine-sensitive potassium channel(KAch),hyperpolarizationactivated cyclic nucleotide-gated ion channel subtype 2 and 4(HCN2 and HCN4),induced pluripotent stem cell dericed cardiomyocyte(IPSC-CM) and Na+-Ca2+-exchanger(NCX).Results 0.1 mg/ml Tiaomiyin granules significantly inhibited electric current of Cav3.2(18.94% ± 2.19%) and NCX(28.46%±9.74%).1 mg/ml Tiaomiyin granules significantly inhibited electric currents of hERG(43.29%±0.09%),Cav3.2(34.72%±0.61%),KATP(38.44%±2.67%),HCN4(30.64%±1.94%) and NCX(64.25%±25.29%),and significantly increased electric currents of KV7.1(34.49%±4.53%)(P<0.05).At the same time,Tiaomayin granules induced the prolongation of IPSC-CM action potential duration,paired t test).Meanwhile,Tiaomaiyin granules could prolong action potential’s time course of IPSC-CM,prolonging the effective refractory period of the heart.Conclusion Tiaomiyin granules could prolong action potential’s time course of IPSC-CM and inhibit the electric current in NCX and hERG channels,it may be the main mechanism of anti-arrhythmic effect.That inhibiting calcium electric current of CaV3.2 and atrionector pace-making electric current of HCN4 may play a role in lowering heart rate.That enhancing KV7.1 electric current may offsetting overextended time course of action potential and QT interval caused by inhibiting the hERG channel,its inhibitory effect on KATP may play a protective role in myocardial ischemia.