HypercapniaVasodilator AgentsCarbon DioxideVasodilationAnoxiaChemoreceptor CellsRespirationAcidosis, RespiratoryHypocapniaPulmonary VentilationPartial PressureOxygenCerebrovascular CirculationNitroprussideRegional Blood FlowNitric OxideRespiratory MechanicsBlood PressureVascular ResistanceBlood Gas AnalysisAcetylcholineHemodynamicsApneaAcidosisVasoconstrictionTidal VolumeAcid-Base EquilibriumCarotid BodyNitroglycerinForearmNG-Nitroarginine Methyl EsterPia MaterEndothelium, VascularPulmonary CirculationArteriolesHeart RateHyperoxiaDogsVasomotor SystemPapaverineBlood Flow VelocityHydralazineCerebral ArteriesPlethysmographyBradykininHyperemiaRats, Sprague-DawleyVasoconstrictor AgentsHyperventilationNitric Oxide SynthaseHydrogen-Ion ConcentrationEpoprostenolAsphyxiaomega-N-MethylarginineHypertension, PulmonaryCalcitonin Gene-Related PeptideNitroarginineArginineHypoventilationCoronary CirculationAdenosineLaser-Doppler FlowmetryDose-Response Relationship, DrugRats, WistarPulmonary ArteryPlethysmography, Whole BodyMesenteric ArteriesPhrenic NerveArteriesOxygen ConsumptionDiaphragmRespiration, ArtificialAcetazolamidePulmonary Gas ExchangeMuscle, Smooth, VascularIndomethacinCatsRespiratory Physiological PhenomenaAnimals, NewbornCoronary VesselsRespiratory MusclesRespiratory InsufficiencyIntercostal MusclesSplanchnic CirculationReflexAnesthesiaMedulla OblongataPhenylephrineRespiratory CenterEnzyme InhibitorsInsufflationTime FactorsEndothelium-Dependent Relaxing FactorsBicarbonatesHypotensionDoxapramBrain StemWakefulnessPerfusionVagotomy