DigitoxinCardiac GlycosidesGlycosidesDigoxinCardenolidesDigitalis GlycosidesOuabainDigitalisSodium-Potassium-Exchanging ATPaseDigitoxigeninCardanolidesBufanolidesCardiotonic AgentsDeslanosideStrophanthidinHeartRubidiumNeriumProscillaridinPotassiumMyocytes, CardiacStrophanthinsGlycoside HydrolasesSodiumPlant PoisoningGuinea PigsMyocardial ContractionMyocardiumVeratrineDigoxigenin