Influences of different stress models on the antioxidant status and lipid peroxidation in rat erythrocytes.

The aim of this study was to investigate the influences of different stress models on the antioxidant status and lipid peroxidation (LPO) in erythrocytes of rats. Swiss-Albino female rats (3 months old) were used in this study. Rats were randomly divided into the following four groups; control group (C), cold stress group (CS), immobilization stress group (IS) and cold + immobilization stress group (CS + IS). Control group was kept in an animal laboratory (22 +/- 2 degrees C). Rats in CS group were placed in cold room (5 degrees C) for 15min/day for 15 days. Rats in IS group were immobilized for 180 min/day for 15 days. Rats in CS + IS group were exposed to both cold and immobilization stresses for 15 days. At the end of experimental periods, the activities of glucose-6-phosphate dehydrogenase (G-6-PD), Cu,Zn-superoxide dismutase (Cu,Zn-SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), and concentration of reduced glutathione (GSH) were measured. LPO was determined by measuring the contents of thiobarbituric acid-reactive substances (TBARS). Cu,Zn-SOD activity and TBARS concentration were increased after cold and immobilization stresses, but CAT and GSH-Px activities and GSH levels were decreased. Immobilization stress decreased the activity of G-6-PD. The activities of G-6-PD, CAT and GSH-Px, and the level of GSH were lower in CS + IS group than in the control group. Cu,Zn-SOD activity and TBARS levels were increased in CS + IS group when compared with the control group. From these findings, three stress models are thought to cause oxidative stress.