EVALUATION OF ANTIDEPRESSANT EFFECTS OF ZINC ACETATE IN MICE

Background: Depression is a debilitating mental health disorder that causes changes in physical activity, appetite, sleep and weight. Many studies shown that zinc may have an important role in the pathogenesis of depression. In this study we aimed to evaluate the antidepressant effects of Zinc acetate in mice and to investigate the synergistic effect of zinc acetate with fluoxetine, a standard antidepressant. Methods: After getting approval from ethics committee, 36 male swiss albino mice weighing 20-30 gm were randomly allocated into 6 groups with 6 in each group. First group received normal saline (control), second group received fluoxetine 10 mg/kg (standard). Third, fourth and fifth group received Zinc acetate 10 mg/kg, 20 mg/kg and 40 mg/kg respectively. Sixth group received fluoxetine 10 mg/kg with zinc acetate 10 mg/kg. All the drugs were given through oral route. The effects of the drugs were assessed by recording the immobility time in Tail Suspension Test (TST) and the results were analysed by one way ANOVA followed by Bonferroni post hoc test. Results: The mean immobility time for Control is 236 ± 14 seconds which is significantly higher than that of the Standard Fluoxetine 10 mg/kg group 155 ± 13 seconds (p <0.001). The mean immobility time for zinc acetate 10 mg/kg, 20 mg/kg and 40 mg/kg group were 226±9 seconds, 219±11 seconds and 196 ± 9 seconds respectively. The mean values of these groups were not statistically lower when compared to that of control group. The zinc acetate 40 mg/kg group did not differ significantly from either the control (p=0.228) or fluoxetine (p=0.206), reflecting an intermediate numerical trend. Conclusion: From this study, a numerical dose dependent trend toward reduced immobility time was observed with zinc acetate, most pronounced at 40 mg/kg and warrants further investigation at higher doses or with chronic administration. Also, there is no additional benefit of Zinc acetate over Fluoxetine at the tested dose.