Interaction of sertraline and nimodipine on some behavioural tests in rats.

BACKGROUND Intracellular calcium contributes to the development of affective disorders. Also, calcium channel inhibitors influence the activity of many neurotransmitters and exert antidepressant and anxiolytic properties. OBJECTIVES The aim of this study was to examine the effects of sertraline on anxiety and depressive behaviors and the role of nimodipine, a calcium channel antagonist, on these effects. MATERIAL AND METHODS Forced swimming and elevated plus maze tests were used to assess depression and anxiety respectively in rats. Sertraline (10 mg/kg) was administered repeatedly for 7 days both alone and in combination with single (0.5 mg/kg) and repeated (0.5 mg/kg/7 days) nimodipine administrations. RESULTS Both repeated sertraline (S) and its combination with single nimodipine administration (S + N) significantly decreased the immobility time compared to control. The combination of (S) with repeated doses of nimodipine (N/7d), significantly increased the immobility time compared to (S) and (S + N). Single dose of nimodipine (N) significantly increased the immobility time compared to (S) and (S + N), and decreased the number of divings compared to control. There was no significant difference between groups in terms of struggle and the time spent in closed arms of the elevated plus maze. CONCLUSIONS There was no interaction between a single dose of sertraline and nimodipine when administered in combination, while repeated nimodipine administration reversed the antidepressant-like effect of sertraline. We suggest that L-type calcium channels are involved in the antidepressant-like effect of sertraline. Neither single nor repeated nimodipine administration had a significant effect on both depressive behaviour and anxiety. We also propose that there is no interaction between the effects of sertraline and nimodipine on anxitey behavior.