“The combined … of ZnCl2 (1 mg/kg) with sub-effective doses of fluoxetine (5 mg/kg), …), desipramine (0.1 mg/kg), imipramine (0.1 mg/kg) or bupropion (1 mg/kg) induced a significant reduction in the immobility time … with the groups treated with ZnCl2 or with antidepressants alone.”