PapaverineCoronary VesselsCoronary CirculationVasodilator AgentsVasodilationDipyridamoleCoronary AngiographyDilazepAdenosineDogsCoronary Artery DiseaseNitroglycerinVascular ResistanceCross CirculationCoronary DiseaseHemodynamicsCerebral ArteriesAngioplasty, Balloon, CoronaryBlood Flow VelocityHeartHyperemiaCoronary StenosisTomography, Emission-ComputedCoronary Artery BypassRegional Blood FlowBlood PressureBradykininNitric OxidePerfusionCerebral InfarctionCerebrovascular CirculationHeart RateMyocardiumDose-Response Relationship, DrugCoronary VasospasmCerebral Palsy