[Different trend for changing of mammalian plasma (serum) antioxidant activity after irradiation at large and...

One of the path for research of antioxidant status in vivo is the determination of blood plasma (serum) antioxidant activity (AOA). AOA is an integral parameter for the contribution of different antiradical defense components which particular nomenclature is determined by a used method of definition. In the present work AOA is studied with usage of a system of suppression in vitro by blood plasma (serum) of a Fe(2+)-induced oxidation of a substrate from egg yolk lipoproteins. The contribution of separate components of a blood plasma to an integral index of AOA for human blood serum is studied. Urine acid, albumin, reduced glutathione, ascorbat, heparin, peroxidase and catalase had no activity. Apo-beta-lipoprotein, vitamin E, ceruloplasmin and transferring are introduce, possibly, the main contribution to AOA. The significant decrease of AOA was revealed after acute irradiation by gamma-rays of dogs (4.05 Gy) and mice (6 Gy). The irradiation of mice at low-dose (0.2 Gy), vice-versa, result to stimulation of AOA with clear peak value on 5 day. The possible reasons of quality difference for effects of large and low dose radiation with reference to antioxidant system of organism are discussed.