An experimental evaluation of anticonvulsant activity of Vitex-negundo.

Maximal electroshock seizures (MES) in albino rats and pentylenetetarazole (PTZ) induced seizures in albino mice were used to study anticonvulsant activity of Vitex-negundo leaf extract. The ethanolic leaf extract of Vitex-negundo was administered orally in graded doses (250, 500 and 1000 mg/kg p.o) in both the experimental models and the effects were compared with diphenylhydantoin in MES method and valporic acid in PTZ induced seizures method as standard control respectively. The Vitex-negundo in the doses (250, 500 and 1000 mg/kg, p.o) did not show protection against MES to any significant extent but significant post-ictal depression was observed in the dose of 1000 mg/kg body weight in comparison to control. However, sub-protective dose of test drug (100 mg/ kg, p.o) potentiated the anticonvulsant action of diphenylhydantoin. The test drug in the dose (1000 mg/kg, po) showed 50% protection in clonic seizures and 24-hour mortality against PTZ induced seizures. It also decreased number and duration of convulsions significantly. Vitex-negundo potentiated anticonvulsant activity of valporic acid. The anticonvulsant activity of Vitex-negundo has not been found equi-effective with standard drugs. These findings suggest that Vitex-negundo possesses anticonvulsant activity particularly against PTZ induced convulsions. Moreover, the potentiation of diphenylhydantoin and valporic acid by Vitex-negundo indicates that it may be useful as an adjuvant therapy along with standard anticonvulsants and can possibly lower the requirement of diphenylhydantoin and valporic acid.