Effects of Valeriana Officinalis Extract on the Seizure Induced by Picrotoxin in Mice

Neurological effects of Valeriana officinalis have been recognized for many years. In this study, the anticonvulsant activity of methanolic extract of the plant were investigated in mice. Picrotoxin with doses of ۶ and ۱۲.۵ mg/kg were used for induction of seizures. The effects of different doses of methanolic extract of the plant on the variation of beginning time of seizures, the incidence of tonic and clonic seizures and mortality rate were determined. The beginning time of tonic seizures induced by picrotoxin (۶ & ۱۲.۵ mg/kg I.P.) were delayed significantly in group which received extract (۵۰ mg/kg I.P.) ۲۰ min. before picrotoxin administration. Latency of beginning time of tonic seizures in mice which receive picrotoxin ۶mg/kg were increased significantly from ۱۰.۵۸ min to ۱۵ min (P<۰.۰۵ ) and in case of ۱۲mg/kg of picrotoxin from ۵.۸۷ to ۱۰.۸۲ min.(P<۰.۰۱). The incidence of clonic seizures and mortality rate were decreased in this group of animals (P<۰.۰۵, P<۰.۰۱). The results indicated that valerian extract may be effective on generalized tonic, cloinc and tonic - clonic seizures and the dose of ۵۰ mg/kg was enough to produce effective concentration for anticovulsive activity of the extract in mice.