Binding and release of ouabain at low Mg²⁺ in reconstituted human red blood cell ghosts

Abstract

Various conformational states of Na,K-ATPase as pharmacological receptor for cardiac glycosides are recognized by the rate of ouabain binding and release in porous and reconstituted human red blood cell ghosts. At low Mg²⁺, conformational changes become evident in the presence of various ligands which cannot be studied at physiological concentrations of Mg²⁺. By using reconstituted human red cell ghosts containing ATP and little Mg²⁺, it is possible to evaluate the side-specificity of those effects of Na⁺ and K⁺ which have been observed in porous ghosts. Some of the following data are detailed in previous papers (5, 6).