Membrane PotentialsCell MembraneMembranesMembrane LipidsIntracellular MembranesMyocytes, CardiacMembranes, ArtificialCell Membrane PermeabilityMembrane Potential, MitochondrialErythrocyte MembraneMembrane FluidityHeartCalciumMyocardiumPotassiumCells, CulturedBasement MembraneSodiumTime FactorsMitochondriaElectrophysiologyAction PotentialsCell LineIon ChannelsElectric ConductivityModels, BiologicalMembrane Transport ProteinsMitochondrial MembranesMicroscopy, ElectronLipid BilayersHydrogen-Ion ConcentrationMembrane GlycoproteinsPatch-Clamp TechniquesPotassium ChannelsGuinea PigsKineticsAdenosine TriphosphateProtein TransportCardiac OutputArrhythmias, CardiacRats, Sprague-DawleyMyocardial ContractionHeart VentriclesCarrier ProteinsProtein BindingFluorescent DyesBiological Transport, ActiveRabbitsChloridesLiposomesSignal TransductionMicroscopy, FluorescenceSynaptic MembranesMolecular Sequence DataValinomycinMutationMyoblasts, CardiacMicroscopy, ConfocalRats, WistarDogsDose-Response Relationship, DrugApoptosisAnimals, NewbornProtein Structure, TertiaryAmino Acid SequenceNeuronsErythrocytesCell FractionationOuabainCardiac Surgical ProceduresElectric StimulationEscherichia coliCardiomegalyBlotting, WesternTemperatureElectrophoresis, Polyacrylamide GelPhosphatidylcholinesIon Channel GatingMitochondria, HeartRecombinant Fusion ProteinsCytosolSarcolemmaDeath, Sudden, CardiacSodium-Potassium-Exchanging ATPaseDetergentsTetrodotoxinBacterial ProteinsEndoplasmic ReticulumModels, CardiovascularCytoplasmCalcium SignalingBinding SitesCalcium ChannelsTransfectionPermeabilityFluorescent Antibody TechniqueBase SequenceFreeze FracturingDiffusionCell Membrane Structures