PropranololHeart RateAdrenergic beta-AntagonistsHeartAcebutololBlood PressurePractololPropanolaminesNadololPlatelet Factor 3Autonomic Nervous SystemLabetalolIsoproterenolHemodynamicsPindololElectrocardiographyEpinephrinePhysical ExertionDogsReceptors, Adrenergic, betaNorepinephrineAtropineParasympathetic Nervous SystemHeart FailureAtenololElectrocardiography, AmbulatoryOxprenololTime FactorsDouble-Blind MethodDrug InteractionsSympathetic Nervous SystemDose-Response Relationship, DrugMetoprololVagus NervePressoreceptorsHeart Rate, FetalHypertensionBaroreflexRespirationEthanolaminesSympathomimeticsMyocardial ContractionExercise TestReninHeart DiseasesMyocardiumHeart AtriaBradycardiaCross-Over StudiesAdrenergic beta-AgonistsTelemetryCatecholaminesHeart TransplantationRestSignal Processing, Computer-AssistedPhentolamineHeart VentriclesCardiac OutputParasympatholyticsArrhythmias, CardiacOxygen ConsumptionReflexPostureStimulation, ChemicalPhenylephrineAnti-Arrhythmia AgentsClinical Trials as TopicRats, Inbred StrainsHandling (Psychology)AnesthesiaRespiratory RateHeart Defects, CongenitalExerciseMuscarinic AntagonistsAnalysis of VarianceRegional Blood FlowClonidineStroke VolumeFetal HeartCold TemperatureSympatholyticsRats, WistarPlacebosAtrioventricular NodeImmersionInjections, IntravenousElectric StimulationHeart Function TestsReceptors, AdrenergicCardiovascular SystemMyocardial InfarctionRats, Sprague-DawleyCarotid SinusHeart Conduction SystemGuinea PigsVasodilator AgentsCardiotonic AgentsCircadian RhythmRabbitsScopolamine Hydrobromide