Superoxide dismutase (erythrocuprein) and free radicals in clinical chemistry.

Erythrocuprein (superoxide dismutase) has recently been shown to have an enzymic function towards superoxide anions. The discovery of superoxide dismutase, its mode of action, and estimation are reviewed along with a brief introduction to oxygen activation and free-radical chemistry. The formation, activity, and destruction of oxygen free radicals in white blood cells, red blood cells, and subcellular particles are discussed. (a) The production of superoxide anions by white cells during phagocytosis is thought to be advantageous for the overall bactericidal event. (b) Normal red blood cells generate low levels of superoxide anions. Increased levels of free-radical production could play a significant role in accelerating cell ageing (haemolysis). (c) Subcellular particles produce superoxide anions. These as well as organic peroxides have been implicated in drug hydroxylation reactions involving cytochrome P-450.