Runge T M, Stephens J C, Holden P, Havemann D F, Kilgore W M, Dale E M, Dalton R E
Arch Int Pharmacodyn Ther. 1975 Mar;214(1):31-45.
Current pharmacologic texts recognize no significant pharmacodynamic differences between the various cardiac glycosides. To reconsider this concept, a special recording device was constructed so that electrocardiograms and phonocardiograms could be obtained in small mammals without anesthesia or premedication, and a spectrum of cardiac glycosides was studied. Utilizing guinea-pigs, cardiac rate reduction of 20% was sought and achieved with 0.07 mg/kg ouabain, 0.34 mg/kg digoxin and 1.12 mg/kg digitoxin. With comparable rate reduction, digitoxin produced significantly greater shortening of electro-mechanical systole than did ouabain or digoxin (P less than 0.05). Other authors have shown that cardiac glycosides produce slowing of cardiac rate prior to onset of positive inotropic effect. Therefore it is probable that for a given amount of vagal effect (sinoatrial slowing) digitoxin possesses greater positive inotropic effect (abbreviation of electromechanical systole) in guinea-pigs than do ouabain or digoxin. A review of the literature suggests that the same holds true for humans.
当前的药理学文献认为，各种强心苷之间不存在显著的药效学差异。为了重新审视这一概念，我们制作了一种特殊的记录装置，以便在不使用麻醉或术前用药的情况下，从小型哺乳动物身上获取心电图和心音图，并对一系列强心苷进行了研究。利用豚鼠，分别用0.07mg/kg哇巴因、0.34mg/kg地高辛和1.12mg/kg洋地黄毒苷实现了心率降低20%的目标。在心率降低程度相当的情况下，洋地黄毒苷导致的机电收缩期缩短显著大于哇巴因或地高辛（P<0.05）。其他作者已经表明，强心苷在正性肌力作用开始之前会导致心率减慢。因此，对于给定的迷走神经效应（窦房结减慢）量，洋地黄毒苷在豚鼠身上可能比哇巴因或地高辛具有更大的正性肌力作用（机电收缩期缩短）。对文献的回顾表明，人类也是如此。
