Central possible antinociceptive mechanism of naringin

Abstract

Background and Aims: The object of this study was the investigation of the central antinociceptive effects of naringin as well as the association of stimulation of opioidergic, serotonergic, adrenergic, and cholinergic (muscarinic and nicotinic) receptors to the central analgesia of mice due to naringin. Methods: Several intraperitoneal doses (20, 40, and 80 mg/kg) were injected into mice models and analyzed via hot-plate (integrated supraspinal response) and tail-immersion (spinal reflex) for the possible antinociceptive effects of naringin. Moreover, the involved action mechanism was investigated using 80 mg/kg naringin (i.p.) administered to the mice which were previously pre-treated with opioid antagonist naloxone (5 mg/kg, i.p.), serotonin 5-HT2A/2C receptor antagonist ketanserin (1 mg/kg, i.p.), α2-adrenoceptor antagonist yohimbine (1 mg/kg, i.p.) and muscarinic antagonist atropine (5 mg/kg, i.p.), as well as nicotinic antagonist mecamylamine (1 mg/kg, i.p.). Results: It can be claimed that a dose-dependant antinociceptive effect of naringin was noticed for 40 and 80 mg/kg doses in tail-immersion and hot-plate tests, respectively. Furthermore, the improvement of inactivity of naringin-induced response to thermal stimuli was counteracted by mecamylamine and naloxone when tested with the tail-immersion test, and hot-plate analyses. Conclusion: From the data, it was confirmed that naringin presents central antinociceptive effects which may be coordinated by supraspinal/spinal mediated opioidergic and nicotinic (cholinergic) inflection. Nevertheless, it is unclear how naringin organizes the interactions of the aforementioned modulatory systems. To conclude, naringin could be a possible candidate for pain relief management.