Effects of selective inhibitors of serotonin reuptake on the anxiety behavior and activity of the pituitary-adrenal system in prenatally stressed male rats.

We studied effects of the selective inhibitors of serotonin reuptake fluoxetine and paroxetine, which were orally administered at a dose of 5.0 mg/kg from the 1st to 14th days of postnatal life, on the anxiety behavior and hormonal stress reactivity of mature prenatally stressed male rats. We found that prenatal stress decreased the anxiety level in mature male rats. Chronic treatment with paroxetine did not the alter the anxiety behavior of prenatally stressed males. In contrast, treatment with fluoxetine had an anxiogenic effect on their behavior, canceling the effect of prenatal stress on the anxiety behavior of male rats. Prenatal stress considerably affected the dynamics of the stress response of the pituitary-adrenal system, which was seen as disturbances in the regulation of system feedback under conditions of stress-induced activation. Chronic administration of paroxetine or fluoxetine corrected the dynamics of stress-induced levels of corticosterone in the blood of prenatally stressed males. [ABSTRACT FROM AUTHOR]