【摘要】 目的　观察吗啡依赖大鼠脊髓和脑干毒蕈碱型乙酰胆碱受体m1～ 5的表达。方法　以 β actin为内标 ,用RT PCR方法检测m1～ 5的表达。结果　吗啡依赖大鼠脊髓m1～ 5受体和脑干中m1 和m2 表达较正常对照组明显升高 ,注射纳洛酮 1h后脊髓m1～ 4 和脑干m1 表达较依赖组减少。东莨菪碱 (0 5mg·kg- 1 ,ip)或呱伦西平 (10mg·kg- 1 ,ip)明显减少吗啡戒断症状 ,呱伦西平处理后脊髓m1 ,m2 ,m3和m5表达较戒断对照组增加 ,东莨菪碱处理后脊髓m2 ,m3和m4 表达增加。结论　脊髓M受体适应性改变是吗啡戒断症状表达的生物学基础。更多还原

【Abstract】 AIM To observe mRNA expression of muscarinic acetylcholine receptors in spinal cord and brainstem in morphine dependent or withdrawal rats. METHODS The mRNA expression level of m 1, m 2, m 3, m 4 and m 5 were determined by RT PCR, the β actin mRNA expression was used as internal control. RESULTS The mRNA level of m 1, m 2, m 3, m 4 and m 5 in spinal cord and m 1 and m 2 in brainstem were increased significantly during morphine dependence, and the levels of m 1, m 2, m 3 and m 4 in spinal cord and m 1 in brainstem were decreased 1 h after the injection of naloxone (4 mg·kg -1 , ip) in morphine dependent rats. Either scopolamine (0 5 mg·kg -1 ) or pirenzepine (10 mg·kg -1 ) was shown to significantly decrease the morphine withdrawal symptoms in rats. The levels of m 1, m 2, m 3 and m 5 in spinal cord were increased by pretreatment with pirenzepine and the levels of m 2, m 3 and m 4 in spinal cord were increased by pretreatment with scopolamine. CONCLUSION The adaptive expression of muscarinic receptors at spinal and supraspinal levels play important role in mediating morphine dependence and withdrawal in rats.更多还原