Mechanisms of Anticonvulsant Action of Residual Aqueous Fraction (RAF) of the Ethanol Root Bark Extract of Carissa edulis

Abstract

Preparations of Carissa edulis (Vahl) have been used in the Nigerian traditional medicine for the management of fever, sickle cell disease, epilepsy, pain cancer and inflammatory conditions for many years and their efficacy is widely acclaimed among the Hausa communities of Northern Nigeria. The possible mechanism(s) involved in the anticonvulsant action of residual aqueous fraction of ethanol root bark extract of Carissa edulis (RAF) were determined using flumazenil, naloxone, cyproheptadine, bisindolylmaleimide (BIM), ibuprofen and misoprostol. Flumazenil antagonized the anticonvulsant effect of both RAF and diazepam, while BIM promoted their anticonvulsant effect. However, naloxone and cyproheptadine did not affect the RAF anticonvulsant effect. Ketoprofen increased the RAF and valproate anticonvulsant activity while misoprostol did not alter their effects. The interaction studies revealed that GABAergic, glycine, serotonergic and opioid neurotransmission were found to be involved in the RAF anticonvulsant effects.

Keywords: Anticonvulsant, Bisindolylmaleimide, Flumazenil, GABA, serotonergic, opioids