葛根素对豚鼠心肌细胞动作电位及有效不应期的影响

Effect of puerarin on action potential and ERP in guinea pig papillary muscles

目的 观察葛根素对豚鼠乳头肌动作电位及有效不应期的影响 ,以探讨其抗心律失常的作用机制。方法 采用标准玻璃微电极细胞内记录技术。结果 ①葛根素 0 0 0 5 ,0 0 1,0 0 15mmol·L-1能使豚鼠心室肌细胞动作电位复极5 0 %时程 (APD50 )和复极 90 %时程 (APD90 )明显延长 ,APD50分别由 ( 176 4 3± 5 1 3 7)ms延长至 ( 192 86± 60 82 )ms(n=7,P <0 0 5 ) ,( 2 0 0 71± 63 0 8)ms和 ( 2 0 7 71± 65 4 5 )ms(n =7,P <0 0 1) ;APD90 分别由 ( 2 0 0 71± 5 9 75 )ms延长至 ( 2 2 1 4 3± 70 4 6)ms(n =7,P <0 0 5 ) ,( 2 3 5 0 0±5 8 88)ms和 ( 2 4 0 0 0± 5 8 4 5 )ms(n =7,P <0 0 1) ,并且这种延长呈现量效关系。②采用 0 2 ,0 5 ,1,2 ,4Hz频率的方波刺激 ,发现在 0 0 1mmol·L-1时葛根素延长心肌细胞APD50 有明显的非逆向频率依赖性。③使用双脉冲刺激发现在 0 0 1mmol·L-1时葛根素能明显延长心肌细胞的有效不应期 ,由 ( 98 0 0± 16 4 3 )ms延长至 ( 168 0 0± 13 0 4 )ms(n =5 ,P <0 0 1)。结论 葛根素能延长心肌细胞APD50 和APD90 以及心肌细胞有效不应期 ,其抗心律失常的机制源于此作用。

AIM To study the mechanism of puerarin against arrhythmias. METHODS Standard microelectrode intracellular recording technique was used RESULTS ①Puerarin 0 005, 0 01,0 015 mmol·L -1 prolong the action potential duration at 50% and 90% of repolarization (APD 50 ,APD 90 ) respectively APD 50 was prolonged from (176 43±51 37) ms to (192 86±60 82) ms ( n=7, P <0 05), (200 71±63 08) ms and (207 716±4 45) ( n=7, P <0 01), APD 90 from (200 71±59 75) ms to (221 43±70 46) ( n=7,P <0 05), (235 00±58 88) ms and (240 0±58 45) ms ( n=7,P <0 01). They had dose effect relationship. ② Used 0 2, 0 5, 1, 2, 4 Hz stimulating frequency found puerarin has not Reversed Use Dependence (RUD) phenomenon ③Puerarin can prolong the effective refractory period (ERP) from (98 00±6 43) ms to (168 00±13 04) ms ( n=5, P <0 01) CONCLUSION Puerarin can prolong the action potential duration and ERP in guinea pig papillary muscles It may be the mechanism of puerarin against arrhythmias in cellular level.