Psychopharmacological effects of ethanol leaf extract of Setaria megaphylla in mice

Background: Setaria megaphylla (Steud) Dur & Schinz (Poaceae), a perennial grass used traditionally in the treatment of various diseases including central nervous system disorders. Objective: To evaluate the Setaria megaphylla ethanol leaf extract for psychopharmacological effects in mice. Materials and Methods : Antidepressant activity was evaluated in mice using open field, force swimming and tail suspension tests as well as phenobarbitone-induced sleeping time. Anticonvulsant activity was also tested against pentylenetetrazol and aminophylline-induced convulsions. Results: The leaf extract (200-600 mg/kg) increased significantly (p<0.05- 0.001) the line crossing, walling and rearing activities in open field test and reduced significantly (p<0.05-0.001) the immobility time in force swimming and tail suspension tests. The leaf extract antagonized the hypnotic effect of phenobarbitone sodium and offered no protection to animals against convulsions induced by pentylenetetrazol and aminophylline in mice. Conclusion: The leaf extract of S. megaphylla has prominent antidepressant and CNS stimulatory activities which is due to the activities of its phytochemical constituents. Keywords: Antidepressant, Setaria megaphylla , CNS stimulant