Action PotentialsMembrane PotentialsMembrane Potential, MitochondrialCell MembraneMembranesIntracellular MembranesElectrophysiologyCalciumPotassiumPatch-Clamp TechniquesMembrane LipidsElectric StimulationTetrodotoxinElectric ConductivitySodiumPotassium ChannelsNeuronsMembranes, ArtificialGuinea PigsCell Membrane PermeabilityTime FactorsIon ChannelsSodium ChannelsMicroelectrodesMitochondriaErythrocyte MembraneNeural ConductionMembrane FluidityHeart Conduction SystemCells, CulturedHeartAxonsSynaptic TransmissionVentricular FunctionModels, BiologicalTetraethylammonium Compounds4-AminopyridinePotassium Channel BlockersSynapsesRats, Sprague-DawleyIon Channel GatingFluorescent DyesKineticsDendritesTetraethylammoniumChloridesCalcium ChannelsPyramidal CellsBasement MembraneDogsRabbitsHeart VentriclesModels, NeurologicalCalcium SignalingMitochondrial MembranesPurkinje FibersHydrogen-Ion ConcentrationCell LinePapillary MusclesRats, WistarValinomycinModels, CardiovascularMyocytes, CardiacComputer SimulationAdenosine TriphosphateEvoked PotentialsPotassium Channels, Voltage-GatedBariumMembrane Transport ProteinsMyocardiumDose-Response Relationship, DrugExcitatory Postsynaptic PotentialsVoltage-Sensitive Dye ImagingSodium Channel BlockersCesiumCalcium Channel BlockersAnuraMicroscopy, ElectronBiological Transport, ActiveHippocampusArrhythmias, CardiacAnimals, NewbornSynaptic MembranesMembrane GlycoproteinsCarbonyl Cyanide p-TrifluoromethoxyphenylhydrazoneNeurons, AfferentMusclesMotor NeuronsCalcium Channels, L-TypeRefractory Period, ElectrophysiologicalMutationMicroscopy, FluorescenceOuabainLipid BilayersMicroscopy, ConfocalMuscle ContractionProtein TransportAnti-Arrhythmia AgentsIon TransportTemperature