Species-specific Mn2+/Mg2+ antiport from Mg2+-loaded erythrocytes

AbstractMg2+-loaded rat erythrocytes performed Mn+/Mg2+ antiport, which was nonspecifically stimulated by anions and cations. Mn2+/Mg2+ antiport was shown to operate via the Na+Mg2+ antiporter because extracellular Na+ and Mn2+ inhibited the intracellular uptake of each other's ions competitively. Furthermore, Mn2+/Mg2+ antiport and Na+/Mg2+ antiport were identically inhibited by various amiloride derivatives. Na+/Mg2+ antiport of chicken and human erythrocytes cannot perform Mn2+/Mg2+ antiport although chicken erythrocytes took up more Mn2+ than raterythrocytes