Evaluation the effect of acute administration of Oxcarbazepine on morphine withdrawal syndrome in male rats

Abstract

Introduction: One of the important analgesic mechanisms of morphine is the effect on excitatory neurotransmitters such as glutamate, P substance etc. The number of these neurotransmitters increases after a discontinuation of morphine consumption. Oxcarbazepine is evaluated in this study with the hypothesis of reduction of excitatory neurotransmitters. Objective: The goal of this investigation was to evaluate the effect of acute administration of oxcarbazepine on morphine withdrawal symptoms in rats. Materials and Methods: Experiments were carried out on rats weighing between 225 - 275 g. In order to create a dependency, morphine injection was performed 9 days at doses of 5 mg/kg (Day 1), 10 mg/kg (Days 2 and 3), 15 mg/kg (Days 4 and 5), 20 mg/kg (Days 6 to 7) and 25mg/kg (Days 8 and 9) subcutaneously twice a day. At the morning of the ninth day, 60 min after morphine injection, naloxone was injected at a dose of 4 mg/kg intraperitoneally, and then signs of withdrawal syndrome such as jumping, movements like wet dog shake, etc, were recorded for 60 minutes. In the groups treated with oxcarbazepine after injection of morphine, oxcarbazepine was injected in three doses of 160, 80, 40 mg/kg intraperitoneally at ninth day an hour after injecting of the last dose of morphine. Results: Acute treatment with oxcarbazepine not only reduced withdrawal symptoms individually and dose-dependently, but also could significantly (p<0.05) reduce the total symptoms of the withdrawal syndrome. Conclusions: Acute injection of oxcarbazepine, is capable of reducing most of the symptoms of morphine withdrawal syndrome.