Passive potassium transport in human red cells.

The effect of procedures known to stimulate the volume-sensitive KC1 pathway has been studied in human red cells. This system is functional in young, but not mature cells and may mediate large fluxes in individuals with large fractions of reticulocytes. The pathway is apparently latent in mature cells, but may be unmasked by certain procedures suggesting that the transporter is not lost from the membrane during cell maturation.