The interaction of chloride with the sulfate transport system of Ehrlich ascites tumor cells.
The effect of Cl- on SO4(-2) efflux was studied in both Cl--containing and Cl--free ascites tumor cells loaded with 35SO4(-2) to test the hypothesis that Cl--SO4(-2) exchange is mediated by the same mechanism responsible for SO4(-2)-self exchange. The addition of Cl--free, 35SO4(-2) loaded cells to a SO4(-2)-free, Cl- medium results in: (1) SO4(-2) efflux that is dependent on the extracellular Cl- concentration (Km = 4.85 mM; ke = 0.048 min-1 at 50 mM Cl-) and (2) net Cl--uptake that exceeds SO4(-2) loss. Both SITS (4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonate) and ANS (1-anilino-8-napthalene sulfonate) inhibit S04(-2) efflux but are without effect on Cl- uptake. The addition of Cl--containing, 35SO4(-2) loaded cells to a SO4(-2)-free, Cl- medium results in: (1) a slight gain in cellular Cl- and (2) ke for SO4(-2) efflux identical to that for Cl--free cells.
D000085:Acetates / Q000494:pharmacology; D000817:Anilino Naphthalenesulfonates / Q000494:pharmacology; D001557:Benzenesulfonates / Q000494:pharmacology; D001693:Biological Transport, Active / Q000187:drug effects; D001965:Bromides / Q000494:pharmacology; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D002712:Chlorides / Q000378:metabolism / Q000494:pharmacology*; D005459:Fluorides / Q000494:pharmacology; D007454:Iodides / Q000494:pharmacology; D007700:Kinetics; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D013267:Stilbenes / Q000494:pharmacology; D013431:Sulfates / Q000378:metabolism*
D000085:Acetates; D000817:Anilino Naphthalenesulfonates; D001557:Benzenesulfonates; D001965:Bromides; D002712:Chlorides; D007454:Iodides; D013267:Stilbenes; D013431:Sulfates; D012964:Sodium; D005459:Fluorides; D011188:Potassium