NitroprussideMagnesiumMagnesium SulfateMagnesium DeficiencyFerricyanidesMagnesium CompoundsVasodilator AgentsNitric Oxide DonorsMagnesium OxideNitric OxideVasodilationAcetylcholineCyclic GMPHypotension, ControlledForearmMagnesium HydroxideDose-Response Relationship, DrugEndothelium, Vascularomega-N-MethylarginineNG-Nitroarginine Methyl EsterMagnesium ChloridePhenylephrineBlood PressureVasoconstrictor AgentsNitric Oxide SynthaseMuscle RelaxationGuanylate CyclaseArginineTrimethaphanCalciumTreatment OutcomeS-Nitroso-N-AcetylpenicillamineRegional Blood FlowEnzyme InhibitorsNitroargininePenicillamineOxadiazolesDouble-Blind MethodVascular ResistanceMolsidomineVasoconstrictionNitroglycerinTime FactorsAorta, ThoracicMuscle, Smooth, VascularBradykininMethylene BlueRats, Sprague-DawleyNorepinephrineBaroreflexRats, WistarHemodynamicsHeart RatePlethysmographyArteriolesRabbitsDogsPotassiumInfusions, Intra-ArterialVasomotor SystemHypertensionPhosphorusMesenteric ArteriesMicrocirculationMuscle ContractionPurinonesCromakalimAortaArteriesIontophoresisCyanidesPotassium ChlorideNitroso CompoundsQuinoxalinesCoronary VesselsSwine15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic AcidAdministration, OralMineralsSympathetic Nervous SystemDrug Therapy, CombinationDibutyryl Cyclic GMPMagnesium SilicatesKineticsHypotensionInfusions, IntravenousPressoreceptorsDisease Models, AnimalVerapamilSodium NitriteDrug Administration ScheduleAnalysis of VarianceCyclic GMP-Dependent Protein KinasesMuscle, SmoothHydrogen CyanideEclampsiaLaser-Doppler FlowmetryRats, Inbred WKYAdenosine TriphosphateTocolytic Agents