Anticonvulsant and anxiolytic activity of ethanolic extract of Betula utilis bark

Abstract

The hydroalcoholic extract of Betula utilis was subjected to phytochemical investigation, the results revealed the presence of alkaloids, tannins, flavonoids, carbohydrate in hydroalcoholic extract of Betula utilis.

Acute oral toxicity study was performed according to OECD 425 Guidelines and revels that at dose of 2000 mg/kg, 67% of the animals died.  So that 1/20^th and 1/10^th (i.e. 100mg/kg and 200 mg/kg orally) was selected for convulsant and anxiolytic activity.

The extract showed a decrease in the duration of the extensor phase and an increase in percentage protection at doses of 100 and 200 mg/kg. Phenytoin completely inhibited the duration of the tonic extensor phase and protected 100% of animals. Control animals exhibited hind limb tonic extension (HLTE) after the delivery of an electroshock in maximum electroshock (mes) induced convulsion model.

HABE produced a dose dependent increase in time spent in open arm along with an increase in number of open arm entries. HABE at a dose of 100 and 200 mg/kg significantly increased number of entries into the open arms and the time spent there. The magnitude of the anxiolytic effects of 100 mg/kg and 200 mg/kg of HABE was comparable to that of diazepam 2 mg/kg p.o. The increased number of entries into the open arms and the time spent there, indicates the stress alleviating effect of HABE (100 and 200 mg/kg).