NephronsCesium IsotopesJuxtaglomerular ApparatusArteriolesFerrocyanidesRenal CirculationKidney MedullaKidneyKidney TubulesVasoconstrictionMicrocirculationRats, Sprague-DawleyStrontium RadioisotopesKidney GlomerulusKidney CortexKidney Tubules, ProximalGlomerular Filtration RateAbsorptionSclerosisKidney Tubules, DistalRats, Inbred SHRLaser-Doppler FlowmetryAngiotensin IIBlood PressureSodiumPerfusionHomeostasisRats, Inbred WKYAlbuminuriaLoop of HenleKidney Tubules, CollectingDogsUreterInulin