Anticonvulsant activity of Carissa edulis (Vahl) (Apocynaceae) root bark extract.

Abstract

AIM OF THE STUDY:

To investigate the anticonvulsant activity of root bark extract of Carissa edulis.

MATERIALS AND METHODS:

The median lethal dose (LD(50)) of Carissa edulis extract was determined using Lork's method (1983). The anticonvulsant activity of the extract was assessed in pentylenetetrazole (PTZ)-induced convulsion in mice and maximal electroshock test (MEST) in chicks, with benzodiazepine and phenytoin as standard drugs, respectively. While mechanistic studies were conducted using both flumazenil, a GABA(A)-benzodiazepine receptor complex site antagonist and naloxone a non-specific opioid receptor antagonist.

RESULTS:

The median lethal dose (LD(50)) of Carissa edulis was 282.8mg/kg and over 5000mg/kg following intraperitoneal and oral administration, respectively. Carissa edulis produced 40% and 20% protection against convulsion at 5 and 20mg/kg, respectively, compared with 100% protection with benzodiazepine. The mean onset and percentage protection against convulsion in Carissa edulis extract-treated mice were reduced by flumazenil and naloxone. Carissa edulis exhibited dose-dependent inhibition of the convulsion induced by MEST with 20mg/kg providing 90% protection while phenytoin (20mg/kg) produced 100% protection.

CONCLUSION:

These results suggest that Carissa edulis possesses biologically active constituent(s) that have anticonvulsant activity which supports the ethnomedicinal claims of the use of the plant in the management of epilepsy.

• Authors: J Ya'u, A H Yaro, M S Abubakar, J A Anuka, I M Hussaini
• Journal: Journal of ethnopharmacology (J Ethnopharmacol) Vol. 120 Issue 2 Pg. 255-8 (Nov 20 2008) ISSN: 0378-8741 [Print] Ireland
• PMID: 18822365 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Anticonvulsants
• Plant Extracts
• Naloxone
• Flumazenil
• Phenytoin

Topics

• Administration, Oral
• Animals
• Anticonvulsants (administration & dosage, isolation & purification, toxicity)
• Apocynaceae (chemistry)
• Chickens
• Disease Models, Animal
• Dose-Response Relationship, Drug
• Female
• Flumazenil (pharmacology)
• Injections, Intraperitoneal
• Lethal Dose 50
• Male
• Mice
• Naloxone (pharmacology)
• Phenytoin (pharmacology)
• Plant Bark
• Plant Extracts (administration & dosage, pharmacology, toxicity)
• Plant Roots
• Seizures (drug therapy)
• Toxicity Tests, Acute