Chappell S P, Henderson A H, Lewis M J
Eur J Pharmacol. 1985 Mar 26;110(1):129-32. doi: 10.1016/0014-2999(85)90039-1.
The negative inotropic effects of two dihydropyridine and two non-dihydropyridine calcium slow channel blocking drugs were studied using ferret isolated papillary muscle preparations contracting both isotonically and isometrically. The degree of inotropic depression was found to be dependent on the frequency of stimulation for all four agents. Frequency dependence of inotropic effect was of the order: nifedipine less than felodipine less than diltiazem less than verapamil.
利用雪貂离体乳头肌标本在等张和等长收缩状态下，研究了两种二氢吡啶类和两种非二氢吡啶类钙慢通道阻滞剂的负性肌力作用。结果发现，所有这四种药物的肌力抑制程度均取决于刺激频率。肌力作用的频率依赖性顺序为：硝苯地平＜非洛地平＜地尔硫䓬＜维拉帕米。
