[Lipid peroxidation and the antioxidant defense system in hypergravity-exposed human].

Nine human subjects at the age of 25 to 45 participated in the studies of effects of the +G endurance limits: 8.30 +/- 0.30 +Gx (chest-back) and 6.51 +/- 0.28 +Gz (head-pelvis). Blood samples were collected 7 days prior to, in an hour and in 1 and 7 days after centrifugation. Blood serum was analyzed for lipid peroxidation (LPO) products such as diene conjugates, malone dialdehyde, schiff bases, and also antioxidant defense system (AOS) components including tocopherol, glutathione peroxidase (GP) activity, catalase and total antioxidant activity. Exposure to +Gx and +Gz resulted equally in LPO inhibition. AOS activation was accounted for water-soluble GP and catalase; however, it should not be excluded that LPO intensity declined due to the trend of biomembranes phase state toward a greater viscosity. LPO inhibition was found more pronounced following exposure to +Gz but not +Gx.