Study on the anticonvulsant activity of thymoquinone, the major constituent of Nigella sativa L. seeds, through intracerebroventricular injection

Abstract

Background: Thymoquinone, the major constituent of Nigella sativa seeds, is a biologically active compound, which possesses several pharmacological effects. Objective: The aim of the present study was to evaluate the anticonvulsant effect of thymoquinone through intracerebroventricular (i.c.v.) injection. Method: The anticonvulsant effects of thymoquinone, the major constituent of Nigella sativa seeds, were investigated using pentylenetetrazole (PTZ)-induced seizure model. Results: In PTZ-induced epileptic seizures, the i.c.v. injection of thymoquinone (200 and 400 mol) prolonged the onset and reduced the duration of tonic-clonic seizures. The protective effect of thymoquinone against lethality was 45% and 50% in the mentioned doses, respectively. In this study, flumazenil (1 nmol, i.c.v.) reversed the anticonvulsant activity of thymoquinone. Also, pretreatment with naloxone (10 mol, i.c.v.) antagonized the prolongation of tonic-clonic seizure latency, as well as reduction in seizure duration both induced by thymoquinone (200 mol, i.c.v.). Conclusion: These results indicate that thymoquinone may possess anticonvulsant activity probably through an opioid receptor-mediated increase in GABAergic tone.

Keywords

• thymoquinone
• nigella sativa
• anticonvulsant
• pentylenetetrazole
• stereotaxy