STUDY ON EXPLORATION OF EFFECT OF VOLTAGE GATED CALCIUM CHANNEL BLOCKERS ON THE ANTI DEPRESSANT ACTION OF IMIPRAMINE AND ALPRAZOLAM

Background: Imipramine is a tricyclic anti depressant drug. Alprazolam is a benzodiazepine sedative drug, but it has also antidepressive action. Voltage gated calcium channel blockers are well known antihypertensive, anti anginal, anti arrhythmic drugs. Objective: In this study I explored the effects of calcium channel antagonists on the antidepressant action of alprazolam and imipramine. Materials And Methods: Despair swim test model was used to study the anti depressive effect on the Male Sprague-Dawley rats. Rats were divided into nine groups (n = 6 per group). One group received a single dose of Tween 80 solution, as because it was used as vehicle for all the drugs; two groups each received a single dose of the antidepressant alone (alprazolam or imipramine); two groups each received a single dose of the calcium channel blocker (nifedipine or verapamil); four groups each received a single dose of the calcium channel blocker followed by a single dose of the antidepressant (with same doses used for either in the previous four groups). Drug administration was performed concurrently on the nine groups. Results: The anti depressant action of both imipramine and alprazolam was confirmed by this study. . Both verapamil & nifedipine delays the onset of immobility, when administered separately. Verapamil potentiate the antidepressive effect of both imipramine & alprazolam. When nifedipine was combined with imipramine , there was delay in the onset of immobility and was greater than their single use. . Either imipramine or nifedipine produced a delay in the onset of immobility of 75% and 81%, respectively, compared to the control( p< 0.05) and combining nifedipine with imipramine led to a delay of 73% in the onset of immobility compared to the control ( p< 0.05). Conclusion: Combination of voltage gated calcium channel blocker with imipramine and alprazolam was some positive effect on the antidepressant action. Key words: Anti depressive action, Sedative, Voltage gated calcium channel, Alprazolam, Imipramine.