转轮运动对小鼠吗啡条件性位置偏爱的建立、消退及重建的影响

目的:研究转轮运动对小鼠吗啡条件性位置偏爱(conditioned place preference,CPP)的建立、消退及重建的影响。方法:每次吗啡CPP训练之后,均将动物置于特制的带有转轮的饲养笼内6 h;在CPP测试之后,动物每天在训练箱中自由穿梭,进行CPP消退训练;待CPP消退之后,皮下注射(sc)10 mg.kg-1吗啡点燃。结果:非转轮运动组和转轮运动组的小鼠经过吗啡CPP训练后,在伴药箱的时间较训练前均显著增加(P<0.001),但两组间没有明显差异;两组小鼠的吗啡CPP消退过程也没有明显差异(P>0.05)。sc吗啡点燃后,非转轮运动组CPP能够重建,而转轮运动组CPP未能重建;结论:转轮运动对吗啡CPP的建立及消退均没有影响,但可以抑制吗啡CPP的重建。

THE EFFECT OF RUNNING-WHEEL ON THE ESTABLISHMENT,EXTINCTION AND REINSTATEMENT OF MORPHINE CONDITIONED PLACE PREFERENCE IN MICE

Objective:To detect the effects of running-wheel on the establishment,extinction and reinstatement of morphine CPP in mice.Methods:The animals were put into the special cages with running-wheel apparatus 6 h after morphine CPP training.After the post-conditioning test of CPP,the mice were trained for extinction of morphine CPP by allowing the animals to run cross the CPP chambers freely.Subcutaneous injection of morphine(10 mg·kg-1) was used to reinstate the morphine CPP after its extinction.Results:After morphine CPP training,the time spent in the morphine-paired chamber increased significantly in both running-wheel group and non-running-wheel group compared with that in the pre-conditioning test(P<0.001),but there was no significant difference between the two groups(P>0.05).In addition,there was no difference between the two groups at extinction training stage(P>0.05).However,the extinguished CPP could be reinstated in non-running-wheel group,but not in running-wheel group in priming test.Conclusion:Running-wheel inhibited the reinstatement of morphine CPP,whereas had no effects on the establishment and extinction of morphine-induced CPP.