EFFECTS OF METABOLITES OF PRIMAQUINE AND ACETANILID ON NORMAL AND GLUCOSE-6-PHOSPHATE DEHYDROGENASE-DEFICIENT ERYTHROCYTES

Hydroxylated metabolites of primaquine and acetanilid increased the mechanical, but not the osmotic, fragility of glucose-6-phosphate dehydrogenase (G-6-PD)-deficient human erythrocytes more than that of normal erythrocytes. These metabolites generally decreased glutathione content and increased methemoglobin content more markedly in G-6-PD-deficient than in normal erythrocytes. Parent drugs were inactive at the same concentrations. Mechanical fragility is suggested as a useful technique for testing drug metabolites in vitro for hemolytic actions that they might exert in vivo. It may also serve to investigate the mechanism by which drug metabolites exert oxidant effects on the erythrocyte membrane.