Briand V, Laurent S, Schmitt H
Laboratoire de Pharmacologie Cardiovasculaire et Unité INSERM U228, Paris, France.
Eur J Pharmacol. 1989 Jul 18;166(2):339-43. doi: 10.1016/0014-2999(89)90080-0.
The negative inotropic potencies (IC50) of the calcium channel blockers nicardipine (12 +/- 2 nM) and nifedipine (9 +/- 2 nM) measured in cultured chick embryo ventricular cells were not significantly different. Exposure of the cells to isoproterenol potentiated the negative inotropic effect of low concentrations of nicardipine (10(-9)-10(-8) M) and decreased the effect of higher concentrations (10(-7) M). In contrast, isoproterenol shifted the entire dose-response curve for nifedipine to the right. These results provide evidence that activation of beta-adrenoceptors modulates the negative inotropic effect of nifedipine and nicardipine differently.
在培养的鸡胚心室细胞中测得的钙通道阻滞剂尼卡地平（12±2 nM）和硝苯地平（9±2 nM）的负性肌力效价（IC50）无显著差异。将细胞暴露于异丙肾上腺素可增强低浓度尼卡地平（10⁻⁹ - 10⁻⁸ M）的负性肌力作用，并减弱高浓度（10⁻⁷ M）时的作用。相比之下，异丙肾上腺素使硝苯地平的整个剂量 - 反应曲线右移。这些结果证明β - 肾上腺素能受体的激活对硝苯地平和尼卡地平负性肌力作用的调节方式不同。
