Kinetic independence between red cell anion exchange and urea transport.
Urea equilibrium exchange fluxes were measured in human red cells under conditions which recruit the anion transporter into an outward-facing or an inward-facing state (with respect to the anion transport site). Regardless of these conditions, urea transport always occurred at the same rate: 41 +/- 2 mol.(kg cell solids.min)-1 with 1.5 M urea at 0 degrees C. These data suggest that the pathway on the band-3 protein which mediates anion transport is kinetically uncoupled from urea transport and is probably not involved in the transport of urea across the red cell membrane.
Fröhlich
O
O
Emory University School of Medicine, Atlanta, GA 30322.
Jones
S C
SC
D001457:Anion Exchange Protein 1, Erythrocyte / Q000378:metabolism*; D027321:Anion Transport Proteins; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism*; D002463:Cell Membrane Permeability; D004910:Erythrocyte Membrane / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D014508:Urea / Q000378:metabolism*
D001457:Anion Exchange Protein 1, Erythrocyte; D027321:Anion Transport Proteins; D002352:Carrier Proteins; D014508:Urea