Kidney TubulesKidney Tubules, ProximalKidneyKidney Tubules, CollectingAbsorptionIntestinal AbsorptionKidney CortexNephronsKidney Tubules, DistalKidney MedullaGlutamineMalpighian TubulesEpitheliumSodium-Potassium-Exchanging ATPaseKidney DiseasesGluconeogenesisTissue DistributionKidney TransplantationMicroscopy, ElectronEpithelial CellsDogsImmunohistochemistryCell LineAcute Kidney InjuryRNA, MessengerMolecular Sequence DataKidney Failure, ChronicSkin AbsorptionKidney GlomerulusBiological AvailabilityPolycystic Kidney DiseasesKidney NeoplasmsSpectrophotometry, AtomicKidney Function TestsJejunumX-Ray Absorption SpectroscopySodiumBiological TransportKidney CalculiRats, Sprague-DawleySpectrophotometryIronIntestine, SmallBicarbonatesRabbitsPolycystic Kidney, Autosomal DominantKidney Concentrating AbilityTime FactorsGlomerular Filtration RateLoop of HenleMicrovilliSpectrum AnalysisAdministration, OralKineticsZincHydrogen-Ion ConcentrationIntestines