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>Evidence for a major route for zinc uptake in human red blood cells: ZN(HCO3)2CL−influx through the CI−/HCO3− anion exchanger
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Evidence for a major route for zinc uptake in human red blood cells: ZN(HCO3)2CL−influx through the CI−/HCO3− anion exchanger
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机译：Evidence for a major route for zinc uptake in human red blood cells: ZN(HCO3)2CL−influx through the CI−/HCO3− anion exchanger
AbstractThe initial rate of Zn2+uptake in human red cells was measured by atomic absorption. A very important fraction of Zn2+uptake was inhibited by DIDS with IC50= 0.3 (μ)M (and by furosemide and bumetanide with IC50of 200 and 500 μ M, respectively). DIDS–sensitive Zn2+uptake exhibited the following properties: (1) It required the simultaneous presence of both external HCO3− and Cl−. (2) In Cl− containing media, it was strongly stimulated by external HCO3− following a sigmoidal (S–shaped) and saturable function, which was fitted by a Hanes equation, with n = 2 and an apparent dissociation constant (for external HCO3−) of 5.3 ± 0.9 mM (mean ± SD of four experiments). The maximal rate of Zn2+uptake at saturating HCO3− concentrations was 50.7 ± 4.8 mmol (liter cells x h)−1. (3) In HCO3− containing media, it was strongly stimulated by external Cl−following a Michaelis‐like equation with an apparent dissociation constant (for external Cl− of 88 ± 11 mM (mean ± SD of three experiments). 4) Bicarbonate‐stimulated Zn2+uptake was inhibited by physiological concentrations of phosphate (sulfate was a much less potent inhibitor than phosphate). A kinetic analysis of the data strongly suggested that zinc was transported by the anion carrier in the form of the monova
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