Effects of Thenorphine on Oxycodone-Induced Physical Dependence in Mice and Rats

OBJECTIVE To study effects of thenorphine on oxycodone-induced physical dependence.METHODS Mice and rats were administrated with doses of oxycodone to induce physical dependence.Withdrawal syndromes were precipitated 6 h following the last administration of oxycodone by the injection of naloxone(5 mg·kg-1,ip).RESULTS Thenorphine(0.062 5,0.25,1.0 mg·kg-1) inhibited jumping and loss of body weight in oxycodone-dependent mice.Thenorphine,at the doses of 0.25,1.0 mg·kg-1,inhibited withdrawal syndromes and loss of body weight in oxycodone-dependent rats.CONCLUSION The present results indicated that thenorphine might inhibit withdrawal syndromes in oxycodone-dependent mice and rats.