A family with mild hereditary xerocytosis showing high membrane cation permeability at low temperatures

Abstract

Radioisotopic cation transport studies are described in a family whose erythrocytes showed an abnormal net efflux of K when cooled to room temperature. This net efflux effect, which was inherited as an autosomal dominant trait, was associated with a few target cells on the blood film and a mild compensated hemolytic state. Measurements of intracellular electrolyte concentrations, cell water and of Na+ and K+ transport rates across the membrane at 37.degree. C were consistent with a diagnosis of mild hereditary xerocytosis. Studies of cation transport in the temperature range 20-37.degree. C revealed that the fluxes attributable to the Na+-K+ pump showed a temperature dependence comparable with that in normal cells, but that the ouabain plus loop-diuretic insensitive fluxes of K+, which probably represent the ''passive diffusional leak'' to K+, were less sensitive to temperature than normal over the range 20-37.degree. C.