阿托伐他汀对兔急性心肌梗死非梗死区瞬间外向钾电流的影响

Effect of atorvastatin on transient outward potassium currents in rabbits with acute myocardial infarction

目的观察阿托伐他汀对急性心肌梗死后非梗死区心肌细胞瞬间外向钾电流（Ito）的影响。方法选用新西兰纯种大耳白兔45只,随机分为3组各15只,分别为正常对照组（CON组）;其他两组均采用结扎兔左前降支方法以建立心肌梗死模型后,一组为心肌梗死组（AMI组）,分离左心室心肌梗死部位非梗死区（AMI-N）细胞,另一组为阿托伐他汀组,从手术日开始连续口服阿托伐他汀5mg/（kg·d）,共7d,后分离AMI-N细胞。采用全细胞膜片钳记录技术分别记录非梗死区（AMI-N）心外膜心肌细胞（Epicardium,Epi）Ito密度。3组均在手术建立模型前抽取静脉血,用生化分析仪测定血清总胆固醇。结果 3组血清总胆固醇水平比较差异无统计学意义（P〉0.05）。3组Epi细胞ItoⅠ~Ⅴ曲线均呈电压依赖的线性曲线,电流密度于＋70m V电压时达峰值,CON组于＋70m V电压时Ito电流密度为（115.83±6.04）p A/p F（n=15cells）,AMI组为（72.29±8.74）p A/p F（n=15cells）,阿托伐他汀组为（86.15±2.64）p A/p F（n=13cells）,3组之间比较有明显差异（P〈0.01或P〈0.05）。结论 AMI非梗死区Epi细胞Ito密度与正常心肌细胞相比存在差异性,阿托伐他汀对心肌梗死非梗死区Ito密度的异常有部分改善作用。

Objective To study the effect of atorvastatin on transient outward potassium currents in rabbits with acute myocardial infarction. Methods 45 purebred New Zealand white rabbits were divided for three groups,each of 15 rabbits,respectively for the normal control group（ CON）; the other two were treated with ligating left anterior descending branch method to establish a model of myocardial infarction,a group of myocardial infarction（ AMI group）,isolated left ventricular myocardial infarction non infarct（ AMI / N） cells and the other group for atorvastatin group,from the date of surgery began continuous oral atorvastatin of atorvastatin 5mg /（ kg·d）,a total of 7 days,separated after AMI-N cells. The serum total cholesterol was determined by biochemical analyzer of three groups. Results No statistical significance in 3 groups of serum total cholesterol level（ P〈0. 05）. Three groups Epi cells ItoⅠ ~ Ⅴ curves showed a linear curve of voltage dependent current density,3 groups of cells in ＋ 70 m V and reached a peak voltage. Con group in voltage ＋ 70 m V Itovoltage when the current density was（ 115. 83 ±6. 04） p A / p F（ n = 15cells）,AMI group was（ 72. 29 ± 8. 74） p A / p F（ n = 15cells） and atorvastatin group was（ 86. 15 ± 2. 64）p A / p F（ n = 13cells）,the difference was significant of three groups（ P〈0. 01 or P〈0. 05）. Conclusion There has difference bwtween AMI non infarct zone EPI cells Itoin density and normal myocardial cells,atorvastatin can improve the abnormal Itorelated to myocardial.