Extraordinary cardiac effects of 16-epi-gitoxin in comparison to ouabain in cats and dogs.
The contractility and arrhythmogenic effects of 16-epi-gitoxin and ouabain were studied in dogs. ECG alteration-producing and lethal doses of both glycosides were determined in cats. 16-Epi-gitoxin was found to be a glycoside with rapid onset and short duration of action. In case of equal contractile increment ouabain caused a higher percentage of rhythm disturbances in dogs than 16-epi-gitoxin. This finding corresponds to that in cats, in which ECG changes (QRS complex prolongation) occurred after ouabain at a lower percentage of the lethal dose than after 16-epi-gitoxin. Apart from its slight arrhythmogenic effects, 16-epi-gitoxin may be compared with acetylstrophanthidin.
D000818:Animals; D001145:Arrhythmias, Cardiac / Q000139:chemically induced; D002415:Cats; D055598:Chemical Phenomena; D002621:Chemistry; D004071:Digitalis Glycosides / Q000494:pharmacology* / Q000633:toxicity; D004285:Dogs; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D007928:Lethal Dose 50; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D010042:Ouabain / Q000494:pharmacology* / Q000633:toxicity; D013997:Time Factors
D004071:Digitalis Glycosides; D010042:Ouabain