兔陈旧性心肌梗死心室肌细胞膜电容的变化及卡维地洛的影响

Changes of Ventricular Myocytes Membrane Capacitance in Rabbit with Myocardial Infarction and Effects of Carvedilol

目的模拟临床陈旧性心肌梗死(healedmyocardialinfarction,HMI)的卡维地洛(carvedilol,CVD)治疗方式,研究卡维地洛长期口服给药对HMI后心室肌细胞膜电容的影响。方法24只家兔按体重随机分为3组,HMI组(8只),结扎冠状动脉左回旋支,喂养3月;CVD组(8只),手术同HMI组,并于手术前开始服用CVD,每日0.33mg/kg,持续给药至术后共3月;假手术(Sham)组(8只),手术同HMI组,但不结扎冠状动脉、不服用CVD。3月后应用全细胞膜片钳技术检测单个心肌细胞膜电容大小。结果HMI组心肌细胞的膜电容与Sham组相比明显增大,P<0.05;CVD组心肌细胞的膜电容较HMI组有显著性降低,P<0.01。结论卡维地洛长期口服给药可以逆转HMI兔的左室心肌细胞膜电容的增大。

To investigate effects of long-term treatment of oral Carvedilol on ventricular myocytes membrane capacitance in HMI. Methods 30 rabbits were randomly assigned in three groups： HMI group, ligation of circumflex coronary artery; Carvedilol group, with operation the same as HMI group, and administration of oral Carvedilol 0.33mg·kg^-1·d^-1×3m beginning on the day of operation; Sham group, left thoracotomy with no coronary artery ligation. 3 months after surgery, rabbits were harvested. Myocytes were isolated by enzymatic method. The cell membrane capacitance was recorded by using the whole cell patch clamp technique. Results The membrane capacitance of myocytes in CVD group was reduced significantly as compared with those in HMI group which was larger than those in Sham group （P〈 0.05）. Conclusion Long-term treatment of oral Carvedilol may reverse the increase of ventricular myocytes membrane capacitance.