Evaluation of the anticonvulsant effect of Centella asiatica (gotu kola) in pentylenetetrazol-induced seizures with respect to cholinergic neurotransmission

The study described here was carried out to investigate the anticonvulsant effect of different extracts of Centella asiatica with respect to cholinergic activity on pentylenetetrazol (PTZ)-induced seizures. Rats were randomly divided into eight groups of six rats each: nonepileptic rats treated with saline; PTZ (60 mg/kg, IP)-induced seizure rats treated with saline; PTZ-induced seizure rats pretreated with n-hexane, chloroform, ethyl acetate, n-butanol, and water extracts of C. asiatica; and PTZ-induced seizure rats pretreated with diazepam (2 mg/kg body wt). The seized rats pretreated with different extracts were administered a dose of 200 mg/kg body wt orally for 1 week before induction of epilepsy. Increased acetylcholine content and decreased acetylcholinesterase activity were recorded in different brain regions during PTZ-induced seizures. Pretreatment with C. asiatica extracts caused recovery of the levels of acetylcholine and acetylcholinesterase. These findings suggest that C. asiatica causes perceptible changes in the cholinergic system as one of the facets of its anticonvulsant activity.