Effects of Copper and Zinc Status of Rats on Erythrocyte Stability and Superoxide Dismutase Activity

Abstract

Erythrocytes from copper deficient rats, which had normal plasma zinc but low plasma copper (high Zn:Cu), were more stable to osmotic stress than those from controls. Erythrocytes from zinc deficient rats, which had low plasma zinc and high plasma copper (low Zn:Cu), were more fragile than those from controls. Addition of Cu2+ and Zn2+ to normal red cells in vitro to provide a low Zn:Cu ratio increased hemolysis and peroxidation. In general erythrocyte membranes are sensitive to the concentrations of extracellular Cu and Zn. The effects are inversely related, zinc exerting a stabilizing and copper a labilizing effect. Ceruloplasmin levels increased in zinc deficiency but RBC superoxide dismutase activity was unaffected. SOD activity is suggested as a clinical index of tissue copper status.