Mesenteric ArteriesMesenteric Artery, SuperiorPulmonary EmbolismMesenteric Artery, InferiorIntestinal ObstructionArteriesEmbolismAirway ObstructionEmbolism, FatUreteral ObstructionMesenteric Vascular OcclusionPulmonary ArteryCeliac ArterySuperior Mesenteric Artery SyndromeEmbolism, ParadoxicalIntracranial EmbolismRenal ArteryDuodenal ObstructionCerebral ArteriesIntracranial Embolism and ThrombosisFemoral ArteryCarotid ArteriesVasodilationMuscle, Smooth, VascularVasoconstrictionSplanchnic CirculationEmbolism, Amniotic FluidTomography, X-Ray ComputedBasilar ArteryMesenteric VeinsBiological FactorsUrinary Bladder Neck ObstructionUrethral ObstructionVasoconstrictor AgentsAngiographyVasodilator AgentsNasal ObstructionGastric Outlet ObstructionIliac ArterySplenic ArteryTreatment OutcomeEndothelium, VascularVentricular Outflow ObstructionCoronary Artery BypassVertebral ArteryNorepinephrineHepatic ArteryRats, WistarTime FactorsEmbolism, CholesterolConstriction, PathologicCarotid Artery, InternalPhenylephrineMyographyRadial ArteryDuodenostomyMammary ArteriesSubclavian ArteryAcetylcholineStentsVenous ThrombosisVena Cava, SuperiorRats, Sprague-DawleyBlood PressureCoronary VesselsCarotid Artery DiseasesMuscle ContractionLacrimal Duct ObstructionDose-Response Relationship, DrugRetrospective StudiesEmbolectomyRats, Inbred WKYMuscle RelaxationArterial Occlusive DiseasesNitric OxidePostoperative ComplicationsAneurysmBrachial ArteryFollow-Up StudiesAnticoagulantsProspective StudiesVentilation-Perfusion RatioSuperior Vena Cava SyndromeSuperior ColliculiDogsEndothelium-Dependent Relaxing FactorsCarotid Artery, CommonRegional Blood FlowRenal Artery ObstructionAcute DiseaseUltrasonography, DopplerRats, Inbred SHRRabbitsOphthalmic ArteryAorta, ThoracicPotassium ChlorideCharybdotoxinMiddle Cerebral Artery15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic AcidNG-Nitroarginine Methyl Ester