Oxidative stress and haematological changes in immobilized rats

Immobilization stress induces formation of reactive oxygen species (ROS) an d leads to the oxidative injury in various tissues. In this study, the effe cts of immobilization stress on peripheral blood cells distribution, plasma level of thiobarbituric acid reactive substances (TEARS), and activities o f antioxidant enzymes in erythrocytes were investigated in male Fischer rat s. A significant increase in plasma TEARS was observed during and after the stress. Dramatic increases of neutrophils and monocytes imply that ROS for mation resulted from their activation. Furthermore, the antioxidant activit ies of catalase and superoxide dismutase (SOD) in erythrocytes were dramati cally increased during and after the stress, while a large fall in erythroc yte number was observed. These findings suggest that the activation of immu ne cells can be a source of the immobilization-induced ROS production, and that antioxidant enzymes in erythrocytes play an important role in preventi ng the ROS-induced injuries.