黄芪对兔急性心肌梗死心室肌细胞钠通道电流的影响

Effect of Astragalus Membranaceus on sodium currents in ventricular myocytes from infarcted rabbit heart

目的 :研究黄芪对兔急性心肌梗死 (AMI)后心室肌细胞钠通道电流 (INa)的影响。方法 :采用结扎兔冠状动脉左前降支的方法建立 AMI动物模型 ,应用膜片钳全细胞记录方法 ,观察 AMI后 1周心外膜梗死区心肌细胞 INa的变化。结果 :AMI后 1周 INa的 I- V曲线明显上移。对照组 INa电流密度峰值 (- 30 m V)为 4 5 .5 0± 5 .33p A/ p F(n=12 ) ,AMI组为 2 2 .4 8± 4 .6 2 p A/ p F(n=14 ) ,显著低于对照组 (P<0 .0 1) ;黄芪组为 37.14± 3.79p A / p F(n=15 ) ,与 AMI组相比 ,显著增大 (P<0 .0 5 )。结论 :AMI后 1周梗死区心室肌细胞 INa明显下降 ,黄芪可以使 AMI后下降的 INa趋于正常 ,逆转 AMI后形成的电重构。

AIM :To study the effect of Astragalus Membranaceus(AM) on the current density of sodium channel(I Na) in cells from the epicardial border zone of the infarcted rabbit heart. METHODS:Rabbits were infarcted by ligation of the left anterior descending coronary artery,1 week later, I Na was recorded using whole cell patch-clamp techniques from the infarcted heart(AMI), and compared with the I Na from the noninfarcted heart(CON)and AM treatment group(AM). RESULTS:Peak I Na current density(at -30 mV) was significantly reduced in AMI(22.48±4.62 pA/pF,n=14)compared with CON (45.50±5.33 pA/pF,n=12,P<0.01). However, AM(37 14±3.79 pA/pF,n=15) increased the peak I Na density significantly compared with AMI(P<0.05). CONCLUSION: I Na was reduced in myocytes of infarcted zone. AM could inhibit the decrease of I Na and normalize it, suggesting the presence of reverse remodeling.