Intensity of Oxidative and Antioxidant Processes in the Brain of Rats with Various Behavioral Characteristics during Acute Stress

We studied the effect of acute emotional stress (1-h immobilization with simultaneous electrocutaneous stimulation) on the prooxidant-antioxidant balance in emotiogenic structures of the brain in rats with various behavioral characteristics. TBA-reactive substance content in the hypothalamus of rats remained practically unchanged after stress exposure. Opposite change in activity of antioxidant defense enzymes in this structure of the brain in behaviorally active specimens probably compensate for the possible variations in LPO during emotional stress. Activities of glutathione reductase and Cu/Zn-containing SOD in the hypothalamus of passive animals decreased under these conditions. As differentiated from active rats, emotional stress in passive specimens was accompanied by the accumulation of TBA-reactive substances in the sensorimotor cortex and amygdala. The observed increase in glutathione peroxidase activity in passive animals probably serves as a secondary compensatory reaction to LPO activation. Our results illustrate specific changes in free radical processes and antioxidant defense in emotiogenic structures of the brain in rats with various behavioral characteristics after acute stress. These changes were more pronounced in behaviorally passive specimens than in active animals. It was probably related to differences in the oxidative status of CNS in rats with various prognostic resistance to similar stress factors.