论文部分内容阅读
目的观察罗哌卡因和布比卡因对豚鼠心室肌细胞L-型钙电流(ICa-L)的影响,探讨其心肌负性肌力作用的机制。方法以急性酶解法获得豚鼠的单个心室肌细胞,用标准的全细胞膜片钳技术记录ICa-L。结果100/μmol/L的罗哌卡因和布比卡因分别使豚鼠心室肌细胞ICa-L峰值降低(37±3)%和(42±5)%,两者比较差异有统计学意义(P<0.05);两种药物均使电流密度-电压曲线上移,但不改变激活ICa-L的电压和曲线的形态。罗哌卡因和布比卡因均呈浓度依赖性阻滞豚鼠心室肌细胞ICa-L,半最大抑制浓度分别为212±38、(161±20)μmol/L。结论罗哌卡因和布比卡因均呈浓度依赖性阻滞豚鼠心室肌细胞ICa-L,可能是其产生心肌负性肌力作用的主要机制。
Objective To investigate the effects of ropivacaine and bupivacaine on L-type calcium current (ICa-L) in guinea pig ventricular myocytes and to explore the mechanism of myocardial negative inotropic effect. Methods Single ventricular myocytes of guinea pigs were obtained by enzymatic digestion. ICa-L was recorded by standard whole-cell patch clamp technique. Results The ICa-L peak of guinea pig ventricular myocytes was reduced by (37 ± 3)% and (42 ± 5)% respectively with ropivacaine and bupivacaine at 100 / μmol / L, the difference was statistically significant <0.05). Both drugs advanced the current density-voltage curve but did not change the voltage and curve shape that activated ICa-L. Both ropivacaine and bupivacaine inhibited ICa-L in guinea pig ventricular myocytes in a concentration-dependent manner, with the maximum inhibitory concentrations of 212 ± 38 and 161 ± 20 μmol / L, respectively. Conclusion Both ropivacaine and bupivacaine can inhibit the ICa-L of guinea pig ventricular myocytes in a concentration-dependent manner, which may be the main mechanism of myocardial negative inotropic effect.