参松养心胶囊对兔心肌梗死1周后瞬间外向钾电流跨壁异质性的影响

目的探讨参松养心胶囊对急性心肌梗死(AMI)1周后心外膜梗死边缘区心肌细胞瞬间外向钾电流(Ⅰ_(to))的影响。方法30只兔随机分为3组:对照组、AMI组和参松养心胶囊+AMI组各10只,后2组采用结扎冠状动脉左前降支的方法建立兔心肌梗死模型。采用膜片钳技术观察参松养心胶囊对左心室梗死边缘区心外膜(Epi)、心内膜(Endo)和中层(M)心室肌细胞Ⅰ_(to)密度及Ⅰ_(to)失活曲线的改变。结果AMI组细胞的Ⅰ_(to)电流密度明显降低,Epi与M、Endo之间差异较明显(P<0.01);参松养心胶囊+AMI组Epi细胞Ⅰ_(to)电流密度进一步降低,与AMI组Epi细胞比较差异有统计学意义(P<0.01),而3层细胞间差异无统计学意义(P>0.05)。3组Ⅰ_(to)失活曲线形态无明显变化,参松养心+AMI组Endo细胞失活曲线右移,与AMI组比较差异有统计学意义(P<0.01)。结论心肌梗死对Ⅰ_(to)的跨壁异质性有明显影响,参松养心胶囊减弱心肌梗死后Ⅰ_(to)的跨壁异质性。

Effects of Shensongyangxin capsule on the transient outward potassium current(Ito) heterogeneity of myocytes from rabbit myocardial infarction model

Objective To investigate the effect of Shensongyangxin capsule on the transient outward current （ Ito ） of rabbit myocytes remote from epicatdium infarcted zone at I w after acute myocardial irffarctiou （AM1）. Methods 30 Rabbits were randomly separated into 3 groups：control group, AMI group and Shensongyangxin capsule ＋ AMI group,rabbits in the last 2 groups were induced AMI with left anterior descending artery ligation. Whole cell palch clamp technique was app）Jed to record the current density and inaetivation curve of Ito in rabbit myoeytes remote from infarcted zone,included epicardium （Epi） ,endoeardium （Endo） and media myocardium （M）. Results The current density of Ito in the AMI group was lower than control group, and there was significant difference among Epi, M and Endo（ P 〈0.01 ）,the Epi cell Ito current density was lower than that in AM] group （ P 〈0.01） , there was no difference among the three layers cells in Shensongyangxin capsule treatment group（ P 〉 0.05 ）. No obviously change was found in inactivation curve of Ito in three groups, while the curve of Endo cell shifted right in Shensongyangxin capsule treatment group,and there was significant differences when compared with AMI group （ P 〈 0.01 ）. Conclusion It demonstrated that the heterogeneity of Ito current density was obviously in myocardial intarction, and Shensongyangxin capsule could attenuate the heterogeneity.