DigitalisDigitalis GlycosidesDigitoxinDigoxinDigitoxigeninCardenolidesLanatosidesCardiac GlycosidesCardanolidesOuabainStrophanthinsSodium-Potassium-Exchanging ATPaseStrophanthidinToxicity TestsDeslanosideCardiotonic AgentsPenstemonPlants, MedicinalHeart FailureArrhythmias, CardiacAnti-Arrhythmia AgentsPlants, ToxicToxicity Tests, AcuteDogsPurkinje FibersBufanolidesDiureticsHeart BlockDose-Response Relationship, DrugTachycardiaSaponinsApneaRubidium