纳洛酮对东莨菪碱所致大鼠空间工作记忆障碍的影响

Effect of naloxone on scopolamine-induced impairment of spatial working memory in rats in Morris water maze task

目的研究纳洛酮对东莨菪碱所致大鼠空间工作记忆障碍的影响。方法大鼠随机分成三组 :正常组、东莨菪碱组和纳洛酮治疗组 ,采用水迷宫延缓性匹配作业。药物实验前 3 0min腹腔注射 ,记录每只大鼠延缓性匹配作业前后两次逃避潜伏期的时间。结果 ( 1)前后两次逃避潜伏期在正常组呈极显著性差异 ( 4 6.4± 17.7,13 .4± 8.2 ,P <0 .0 0 1) ,东莨菪碱组无差异 ( 2 3 .6± 14 .3 ,18.1± 9.8,P >0 .0 5 ) ,纳洛酮治疗组呈显著性差异 ( 2 7.9± 14 .3 ,9.0± 3 .8,P <0 .0 5 )。 ( 2 )前次逃避潜伏期三组间进行比较 ,东莨菪碱组显著低于正常组 ( 2 3 .6± 14 .3 ,46.4± 11.7,P <0 .0 5 )。结论M 型胆碱能受体阻滞剂东莨菪碱能损害大鼠空间工作记忆 ,阿片受体阻滞剂纳洛酮能够改善这种损害 ,说明阿片系统和胆碱能系统在大脑学习记忆过程中存在相互影响。

ObjectiveTo study the effect of naloxone on scopolamine-induced impairment of spatial working memory in rats in Morris water maze performance.MethodsAll naive Rats were accepted pretraining for 2 consecutive days. This procedure was same as the reference memory version of navigation task. Then the training on the working memory version of navigation was followed. A delayed-matching-to sample variant of Morris water maze was adapted. rats were tested 2 sessions per day for 4 days, with each session consisting of two trials separated by a 10s interval, during which rats can utilize working memory to locate the platform at the second trials. On day 7, all rats were divided at random into three groups(n=7): normal group, scopolamine group and naloxone treatment group. The different chemical drugs were delivered into different groups (i.p.) respectively prior to the sessions(the normal group rats received the same volume saline injection refer to scopolamine group ). Then the escape latencies were record. Results The escape latency of normal group in trial 2 was significantly shorter than that in trial 1(P<0.001). There was no significant difference between the escape latencies in trial 1 and in trial 2 at scopolamine group(P>0.05). At naloxone treated group, the escape latency in trial 2 was significantly shorter than that in trial 1(P<0.05). In addition, the escape latency of scopolamine group was significantly shorter than that of normal group in trial1. ConclusionNaloxone can improve the effect of scopolamine-induced impairment of spatial working memory in Morris water maze in rats. The result suggests that the opiate system has interaction with the cholinergic system in central nerve system in the process of learning and memory.