The vitamins C (ascorbic acid, 200) and E (mainly (R,R,fl)-a-tocopherol, 201) are believed to be the major antioxidants in human plasma (Bendich etal., 1986; Halliwell and Gutteridge, 1989; Chow, 1991). Other extracellular defences in human plasma are transferrin (binds iron), lactoferrin (binds iron), ferritin (binds iron), caeruloplasmin (oxidizes Fen to Fern), haptoglobin (binds free haemoglobin), haemopexin (binds free haem), albumin (binds copper, traps HOC1), uric acid (202, binds iron and copper, scavenger), bilirubin (scavenger) and glucose (HO' scavenger). Several of the antioxidant proteins are acute-phase proteins related to inflammatory conditions. Further lipid-soluble antioxidants are /3-carotene (203), bilirubin
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