title: Concentrative PAH transport by rabbit kidney slices in the absence of metabolic energy.
abstract: Characteristics of para-aminohippurate (PAH) transport in the absence of intracellular metabolism were studied with Na+, K+-depleted and ouabain-poisoned rabbit kidney cortex slices. The imposition of a NaCl gradient (out to in) resulted in specific stimulation of PAH uptake. PAH accumulated against its concentration gradient when cell [Na+] was less than medium [Na+]. Conversely, renal cells extruded PAH when cell [Na+] exceeded medium [Na+]. Membrane potential measured with triphenylmethylphosphonium revealed that conditions which created an interior-positive membrane potential inhibited the Na+-dependent transport of PAH but caused stimulation of the Na+-independent component. Characteristics of the Na+-dependent PAH transport system in ouabain-poisoned slices were similar to those previously described in metabolically active tissues.
mesh_terms: D000618:Aminohippuric Acids / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D001693:Biological Transport, Active; D002794:Choline / Q000494:pharmacology; D004734:Energy Metabolism; D066298:In Vitro Techniques; D007668:Kidney / Q000378:metabolism*; D007672:Kidney Cortex / Q000378:metabolism; D007679:Kidney Medulla / Q000378:metabolism; D007700:Kinetics; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D011817:Rabbits; D012964:Sodium / Q000494:pharmacology; D013431:Sulfates / Q000494:pharmacology; D010130:p-Aminohippuric Acid / Q000378:metabolism*
chemical_list: D000618:Aminohippuric Acids; D013431:Sulfates; D010042:Ouabain; D012964:Sodium; D002794:Choline; D011188:Potassium; D010130:p-Aminohippuric Acid