Document Type : Original Article


1 Department of Basic Sciences, Faculty of Veterinary Medicine, Urmia University

2 Department of Basic sciences, faculty of Veterinary Medicine, Urmia University


Thymoquinone (TQ) is the main biologically active substance of Nigella sativa black seeds. This chemical compound, TQ, has anti-cancer, anti-inflammatory, anti-diabetic, anti-oxidative and antinociceptive properties. This study was aimed to explore the effect of TQ in the acetic acid-induced visceral nociception. The central mechanisms of the effect of TQ were investigated using cannabinergic (AM251) and α2-adrenergic (yohimbine) antagonists. The lateral ventricle of the brain was cannulated for intracerebroventricular (ICV) injections. Visceral nociception was induced by intraperitoneal (IP) injection of acetic acid (1.00% in a volume of 1.00 mL). Measuring the latency time to first writhe appearance and counting the number of writhes in 5-min intervals for a period of 60 min were performed. Locomotor activity was determined using an open-field test. Oral administration (Per os; PO) of 2.50 and 10.00 mg kg-1 TQ increased the latency time to first writhe appearance and decreased the number of writhes. AM251 (5.00 µg per rat, ICV) and yohimbine (5.00 µg per rat, ICV) partially prevented TQ (10.00 mg kg-1, PO)-induced antinociception. Locomotor activity was not altered by these treatments. The results of the present study showed that TQ has the ability to reduce visceral nociception caused by IP injection of acetic acid. The central mechanisms of this action of TQ might be partially mediated by cannabinergic and α2-adrenegic receptors.


Main Subjects