Modulatory Effects of Morphine and Xylopia aethioica Extract on Kappa Opiod Receptors (KOR), Delta Opioid Receptor (DOR), Pain Hypersensitivity and Motor Functions in Wistar Rats

Abstract

This study investigates the modulatory effects of morphine and Xylopia aethiopica extract on kappa opioid receptors (KOR), delta opioid receptors (DOR), pain hypersensitivity, and motor functions in Wistar rats. We utilized three experimental groups: a control group receiving distilled water, a morphine group receiving either low (5 mg/kg) or high (10 mg/kg) doses after inducing pain, Xylopia aethiopica group received either 25 mg/kg or 50 mg/kg of hydromethanolic extract following similar pain induction. Pain perception was quantified using the tail flick test and Analgesy-Meter while motor functions were assessed through the Rotarod and Climbing/Beam Walk tests. Additionally, molecular docking studies were performed on selected compounds from Xylopia aethiopica to determine their binding affinities to opioid receptors using Vina. Results demonstrated that morphine and Xylopia aethiopica significantly increased tail flick response times, indicating notable analgesic effects, while improving motor functions particularly in animals treated with higher doses of Xylopia aethiopica. Molecular analysis revealed potential interactions between bioactive compounds and opioid receptors, suggesting further therapeutic applications. These findings highlight the potential of Xylopia aethiopica as a natural analgesic and its implications in managing pain and associated motor deficits, the findings further revealed that Morphine and not Xylopia aethiopica is implicated in pain hypersensitivity after long term exposure. Further research should pay attention on improving the pharmacological profiles of  the identified compounds for clinical use.