Abstract
The article presents experimental data on the impact of high dose gamma-radiation exposure (6 Gy) on immune system, lipid oxidation products (LOPs) and antioxidant defense system (AODS) enzymes activity. The study revealed that high dose radiation exposure suppressed the cell-mediated immunity especially with respect to T-lymphocytes and their subpopulations as well as immune defense and adaptation mechanisms. Ionizing radiation exposure led to increase of conjugated lipid dienes and malondialdehyde (MDA), and to inhibition of catalase and glutathione peroxidise activity, thus promoting oxidative stress in most of the examined samples. The results indicate dramatic changes in lipid peroxidation and antioxidant defense system under the radiation stress. Both cell-mediated and humoral immunity inhibition, mononuclear phagocyte system suppression and lipid peroxidation / antioxidant defense imbalance provide a background for immunopathological disorders, provoking radiation-related carcinogenesis. Impairment of functional network related to glutathione-dependent redox catalytic system decreases human antioxidant status, that necessitates specification of new promising methods correcting adaptation.