Kidney CortexCerium IsotopesRenal CirculationRegional Blood FlowCerebral CortexCerebrovascular CirculationStrontium IsotopesLaser-Doppler FlowmetryBlood Flow VelocityKidneyKidney MedullaXenon RadioisotopesUmbelliferonesPregnatrienesBlood PressureRats, Sprague-DawleyVascular ResistanceBrain IschemiaMicrospheresCatsHypotensionNatriuresisPrefrontal CortexDogsCerebral ArteriesBrainVisual CortexCerebral InfarctionTime FactorsOxygenHemodynamicsRats, Inbred StrainsCarbon DioxideGlomerular Filtration RateMotor CortexElectroencephalographyKidney TubulesNG-Nitroarginine Methyl EsterRats, WistarIschemic Attack, TransientArginineKidney DiseasesAuditory CortexSomatosensory CortexNitric OxideElectric StimulationKidney Tubules, ProximalKidney TransplantationPia MaterDisease Models, AnimalCortical Spreading Depression