The role of acute stress and glucocorticoids in withdrawal syndrome sings in morphine dependent mice

Tolerance and dependency are two main problems that have limited morphine administration. There are some evidences indicating that glucocorticoids and stress may play a role in morphine-induced tolerance and dependency. In this study, Male albinos Mice (25 – 30 gr.) were used. Morphine dependency was induced by Marshall method. On test day (day 4), naloxone (2 mg/kg, IP) was injected to induce withdrawal syndrome (WS) signs. Jumping and loss of weight were used as indexes of WS signs. Dexametasone was injected 30 min before induction of WS by naloxone. The rat was stressed in cold water for 1 min 3 min before induction of WS. The results show that dexamethasone and stress significantly diminish WS signs and the effect of stress was significantly higher than that of dexamethasone. The data indicate that glucocorticoids and stress may play an important role in morphine addiction process.