Diminished conditioned responding to the nicotine stimulus by antidepressant drugs with differing specificity for the serotonin and norepinephrine transporter

► Nicotine acquired differential control of goal-tracking conditioned response (CR). ► Antidepressant drugs citalopram, imipramine, and reboxetine blocked the CR. ► Stimulus effects of nicotine involve the noradrenergic and serotonergic systems. ► At some doses, antidepressant drugs alone alter activity and/or dipper entries. ► Non-specific effects, thus, contribute some to the decrease in the CR.