The effect of chronic treatment with antidepressant drugs fluoxetine (20 mg/kg) and imipramine (25 mg/kg) on the number of antibody-producing cells and the main T cell subpopulations in ASC mice characterized by genetic predisposition to depression-like states was studied at the peak of the SE-induced immune response (5×108). Fluoxetine produced an immunostimulatory effect manifested in an increase in the relative and absolute number of IgM antibody-producing cells in the spleen and index of immunoreactivity (CD4/CD8). Administration of fl uoxetine to parental mouse strains without depression (CBA and AKR) had no effect (CBA) or reduced the immune response. The CD4/CD8 ratio did not increase under these conditions. Imipramine was ineffective in the correction of immune reactions in a depression-like state.