Nicotine Potentiates the Antidepressant Effects of Imipramine and Sertraline

Clinical observations suggest the involvement of nicotinic acetylcholine receptors (nAChRs) in depressive illness. There is no clear cut evidence that nicotine produces an antidepressant effect. The antidepressant effect was assessed by the forced swimming test using male albino mice. Nicotine (1.2 mg/kg s.c.) given 15 min. before the test exerted no effect on immobility. Given 30 min before the test, imipramine and sertraline (each 20 mg/ kg i.p.) produced a significant decrease in immobility; coadministration of nicotine (1.2 mg/ kg, 15 min before the test) to either imipramine or sertraline-treated mice resulted in an enhancement in anti-immobility effect. The study further investigated the effect of nicotine, alone and in combination with either imipramine or sertraline on sucrose consumption in mice exposed to 3-weeks application of stressors. There was a reversal of anhedonia 3 weeks after i.p. administration of the antidepressant drugs given alone, and this reversal was enhanced when nicotine was co-administered with them.