| Background: The exact mechanisms of morphine-induced dependence and withdrawal symptoms remain unclear.
In order to identify an agent that can prevent withdrawal syndrome, many studies have been performed. This study
was aimed to evaluate the effect of gap junction blockers; carbenoxolone (CBX) or mefloquine (MFQ); on morphine
withdrawal symptoms in male rat.
Adult male Wistar rats (225 – 275 g) were selected randomly and divided into 10 groups. All groups underwent
stereotaxic surgery and in order to induce dependency, morphine was administered subcutaneously) Sc) at an
interval of 12 hours for nine continuous days. On the ninth day of the experiment, animals received vehicle or CBX
(100, 400, 600 μg/10 μl/rat, icv) or MFQ (50, 100 and 200 μg/10 μl/rat, icv) after the last saline or morphine (Sc)
injection. Morphine withdrawal symptoms were precipitated by naloxone hydrochloride 10 min after the
treatments. The withdrawal signs including: jumping, rearing, genital grooming, abdomen writhing, wet dog shake
and stool weight, were recorded for 60 minutes.
Results: Results showed that CBX and MFQ decreased all withdrawal signs; and the analysis indicated that they
could attenuate the total withdrawal scores significantly.
Conclusion: Taking together it is concluded that gap junction blockers prevented naloxone-precipitated
withdrawal symptoms. |