Iron ion induced haemolysis: effect of caeruloplasmin, albumin and ascorbate (vitamin C).

Human caeruloplasmin (ferroxidase), bovine serum albumin and ascorbate protected washed rat erythrocytes against iron ion stimulated haemolysis, while superoxide dismutase, catalase and other scavengers of "activated oxygen" species had little or no effect. Caeruloplasmin retained its protective action when its oxidase activity was completely inhibited by azide, and when its copper ions had been removed. The effect of caeruloplasmin, apocaeruloplasmin and albumin could not be attributed to a binding of iron ions to protein molecules.