HypotensionBlood PressurePressureHypotension, ControlledBlood Pressure DeterminationHypotension, OrthostaticHypertensionBlood Pressure Monitoring, AmbulatoryIntracranial HypotensionHeart RateAntihypertensive AgentsHydrostatic PressureHemodynamicsBlood Pressure MonitorsSystoleIntracranial PressureVascular ResistanceArterial PressureDiastoleReninTime FactorsRats, Inbred SHRSympathetic Nervous SystemIntraocular PressurePulseCardiovascular SystemCardiac OutputTransducers, PressureBaroreflexTrimethaphanKidneyProspective StudiesRegional Blood FlowPressoreceptorsCircadian RhythmBradycardiaNorepinephrinePosturePost-Exercise HypotensionAnesthesiaRisk FactorsVenous PressureDogsAtmospheric PressureHypertension, RenalCardiovascular DiseasesCentral Venous PressureAir PressureSphygmomanometersRats, Inbred WKYAngiotensin-Converting Enzyme InhibitorsRats, Sprague-DawleyAngiotensin IIAutonomic Nervous System DiseasesDouble-Blind MethodVasoconstrictor AgentsCerebrovascular CirculationSodium Chloride, DietaryAutonomic Nervous SystemSodium, DietaryRenin-Angiotensin SystemDose-Response Relationship, DrugDiet, Sodium-RestrictedFollow-Up StudiesBody WeightPhenylephrineBlood Flow VelocityVentricular PressureNitroprussideBody Mass IndexTreatment OutcomeVasodilationArteriesAnalysis of VarianceEphedrineReference ValuesCardiovascular Physiological PhenomenaTelemetryReflexCross-Sectional StudiesVasodilator AgentsRegression AnalysisBlood VolumeCaptoprilPulmonary Wedge PressureAldosteroneCohort StudiesMonitoring, PhysiologicShockAnesthesia, SpinalHydrochlorothiazideAortaAge FactorsSodiumVasoconstrictionAnesthesia, ObstetricalRats, WistarCross-Over StudiesTilt-Table TestHeart