Antioxidant protection of the brain in rats during acute stress and administration of interleukin-1β.

We studied the effect of IL-1β on antioxidant enzyme activity in emotiogenic structures of the brain (hypothalamus, sensorimotor cortex, and amygdala) in behaviorally passive and active rats with different sensitivity to stress. One-hour immobilization of animals with simultaneous electrocutaneous stimulation was used as a model of stress. An intraperitoneal injection of IL-1β (5 μg/kg) was followed by the decrease in glutathione reductase activity in the hypothalamus of rats. Behaviorally active animals of the IL-1β group were characterized by an increase in the activities of Cu/Zn superoxide dismutase and glutathione peroxidase in the sensorimotor cortex and amygdala, respectively. IL-1β administration was accompanied by activation of Cu/Zn superoxide dismutase and glutathione peroxidase in the amygdala of passive rats. Pretreatment with IL-1β abolished the poststress changes in enzyme activity in the hypothalamus and sensorimotor cortex of active and passive rats, respectively. These data illustrate the specifi c effects of IL-1β on antioxidant protection of CNS tissues in rats with various behavioral characteristics.