Effect of SITS on organic anion transport in the rabbit kidney cortical slice.
The effect of SITS (4-acetamido-4'-isothiocyano-2,2'-disulfonic stilbene) on the transport of organic ions in the rabbit kidney cortical slice was studied. SITS at a concentration of 10(-4) to 10(-3) M significantly decreased the slice-to-medium (S/M) concentration ratio of the organic anions p-aminohippurate (PAH), and 2,4,5-trichlorophenoxyacetate, but had no significant effect on that of the organic cation tetraethylammonium. The S/M ratio of PAH decreased to 0.52 +/- 0.03 (SE) in the presence of 10(-3) M SITS. The inhibition of PAH uptake caused by SITS was reversed in the presence of 0.5% bovine serum albumin in the medium. SITS at a concentration of 10(-4) M had no significant effect on the efflux of PAH. However, there was a small increase in PAH efflux at a concentration of 10(-3) M SITS. A Lineweaver-Burk analysis of the data indicates that SITS competitively inhibits PAH uptake and that SITS has a Ki value of 2.3 X 10(-4) M. SITS had no effect on the tissue water content, [14C]inulin space, or intracellular Na and K concentrations. It is suggested that the primary effect of SITS is to inhibit the entry of organic anions from the medium into the cell across the basolateral membrane.
D015085:2,4,5-Trichlorophenoxyacetic Acid / Q000378:metabolism*; D000618:Aminohippuric Acids / Q000378:metabolism*; D000818:Animals; D000838:Anions / Q000378:metabolism; D001692:Biological Transport; D002412:Cations / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D007672:Kidney Cortex / Q000378:metabolism*; D007700:Kinetics; D011817:Rabbits; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D013267:Stilbenes / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D013757:Tetraethylammonium Compounds / Q000378:metabolism*; D010130:p-Aminohippuric Acid / Q000378:metabolism*
D000618:Aminohippuric Acids; D000838:Anions; D002412:Cations; D013267:Stilbenes; D013757:Tetraethylammonium Compounds; D012710:Serum Albumin, Bovine; D015085:2,4,5-Trichlorophenoxyacetic Acid; D010130:p-Aminohippuric Acid