The activity of fluoxetine (prozac) and tianeptine (coaxil) was studied in outbred male rats under Porsolt and S. Nomura modified forced swim tests. The antidepressant effect of tianeptine was much more pronounced that that of fluoxetine. In the conflict situation test, fluoxetine produced anxiogenic action. In contrast, tianeptine decreased (albeit not reliably) the anxiety. In combination with bicuculline (GABAA receptor blocker), the anxiolytic action was more pronounced for both antidepressants, which was manifested by a significant increase in the number of punished water takes. A neural network explaining the observed behavior is proposed, which includes GABA-ergic intemeurons inhibiting serotonin release from serotoninergic terminals.