title: External anions relieve DIDS inhibition of SO4 efflux from placental membrane vesicles.
abstract: Sulphate efflux from human placental microvillus membrane vesicles was inhibited by external DIDS (KI congruent to 10(-6) M). This inhibition was partially reversed on addition of the translocated substrates sulphate or selenate to the external medium: selenite which is not translocated does not protect against DIDS inhibition. These findings show that the mechanism responsible for sulphate efflux can be modified by substrate in the external medium.
mesh_terms: D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors*; D000838:Anions / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D008871:Microvilli / Q000378:metabolism; D010920:Placenta / Q000378:metabolism*; D012643:Selenium / Q000494:pharmacology; D013267:Stilbenes / Q000037:antagonists & inhibitors*; D013431:Sulfates / Q000378:metabolism*
chemical_list: D000838:Anions; D013267:Stilbenes; D013431:Sulfates; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid; D012643:Selenium; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid