SulfonesPurinesCanadaPhosphodiesterase 5 InhibitorsPiperazinesPhosphodiesterase InhibitorsCyclic Nucleotide Phosphodiesterases, Type 5Erectile Dysfunction3',5'-Cyclic-GMP PhosphodiesterasesVasodilator AgentsPenile ErectionHypertension, PulmonaryCarbolinesImpotence, VasculogenicCyclic GMPPenisOntarioAdministration, OralPhosphoric Diester HydrolasesPyrimidinonesTriazinesBritish ColumbiaPulmonary ArteryAlbertaPriapismQuebecDouble-Blind MethodCross-Over StudiesTreatment OutcomeManitobaNitric OxideClitorisCyclic GMP-Dependent Protein KinasesHypertrophy, Right VentricularPulmonary Wedge PressureVascular ResistanceDihydroergocristineDose-Response Relationship, DrugIloprostNova ScotiaPapaverineDrug Therapy, CombinationHemodynamicsNorthwest TerritoriesAntihypertensive AgentsEjaculationBlood PressureSaskatchewanNunavutTime FactorsAlprostadilYukon TerritoryEpimediumNewfoundland and LabradorCyclic Nucleotide Phosphodiesterases, Type 2Drug InteractionsGuanylate CyclasePentylenetetrazoleCoitusPulmonary CirculationEsophageal Motility DisordersOrgasmVasodilationCREST SyndromeDrug SynergismMilrinoneMonocrotalineEpoprostenolInuitsRats, WistarPrince Edward IslandSulfonamidesMagnesium HydroxideNG-Nitroarginine Methyl EsterDisease Models, AnimalImidazolesPurinonesSafetyCardiomyopathy, RestrictiveCyclic GMP-Dependent Protein Kinase Type IDrug CostsDoxazosinHeart RateExercise TolerancePlacebosPatient SatisfactionExercise TestArctic RegionsPentaerythritol TetranitrateNew BrunswickSteroid 16-alpha-HydroxylaseMice, Inbred ICRRegional Blood FlowNitric Oxide DonorsSingle-Payer SystemPhentolamineCyclic Nucleotide Phosphodiesterases, Type 3VasovasostomyIsosorbide DinitrateArterial Pressure