Selenium (selenate) transport by human placental brush border membrane vesicles.
1. Selenate uptake by human placental brush-border-membrane vesicles was studied in order to establish whether this anion shares a pathway with sulphate. 2. Selenate uptake was found to be saturable with respect to medium selenate and was inhibited by the anion exchange inhibitor 4,4'-diisothiocyano-stilbene-2,2'-disulphonate (DIDS). 3. Anions which have a similar tetrahedral shape to selenate, e.g. chromate, molybdate, tungstate and sulphate, were effective inhibitors of selenate uptake when added to the incubation medium. 4. Sulphate inhibited selenate influx in a dose-dependent fashion; moreover sulphate was found to be a competitive inhibitor of selenate uptake. 5. It is concluded that selenate and sulphate share a pathway for transport in the human placental microvillus membrane.
Shennan
D B
DB
Department of Human Anatomy, University of Oxford.
D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid / Q000031:analogs & derivatives*; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D001692:Biological Transport / Q000187:drug effects; D003470:Culture Media; D005260:Female; D006801:Humans; D008871:Microvilli / Q000187:drug effects / Q000378:metabolism; D010920:Placenta / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D011247:Pregnancy; D012643:Selenium / Q000493:pharmacokinetics*; D013431:Sulfates / Q000378:metabolism
D003470:Culture Media; D013431:Sulfates; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid; C018564:dihydro-DIDS; D012643:Selenium; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid