Estradiol protects against oxidative stress induced by chronic variate stress.

Neurochemical gender-specific effects have been observed following chronic stress. The aim of this study was to verify the effects of chronic variable stress on free radical production (evaluated by DCF test), lipoperoxidation (evaluated by TBARS levels), and total antioxidant reactivity (TAR) in three distinct structures of brain: hippocampus, cerebral cortex and hypothalamus of female rats, and to evaluate whether the replacement with estradiol in female rats exerts neuroprotection against oxidative stress. Results demonstrate that chronic stress had a structure-specific effect upon lipid peroxidation, since TBARS increased in hypothalamus homogenates of stressed animals, without alterations in the other structures analyzed. Estradiol replacement was able to counteract this effect. In hippocampus, estradiol induced a significant increase in TAR. No differences in DCF levels were observed. In conclusion, the hypothalamus is more susceptible to oxidative stress in female rats submitted to chronic variable stress, and this effect is prevented by estradiol treatment.