海马神经元失活对大鼠氯胺酮成瘾消退和空间记忆的影响  

The effects of the hippocampal neuron inactivation on ketamine addiction extinction and spatial memory in rats

作　　者：高靖尧 王艳艳 王晓琴[2] 王功伍[1] 曹军[3] Gao Jingyao;Wang Yanyan;Wang Xiaoqin;Wang Gongwu;Cao Jun(School of Life Sciences,Yunnan Normal University,Kunming 650500;School of Physical Education,Yunnan Normal University,Kunming 650500;School of Ecology and Environmental Science,Yunnan University,Kunming 650500,China)

机构地区：[1]云南师范大学生命科学学院,昆明650500 [2]云南师范大学体育学院,昆明650500 [3]云南大学生态与环境学院,昆明650500

出　　处：《神经解剖学杂志》2022年第6期650-656,共7页Chinese Journal of Neuroanatomy

基　　金：国家自然科学基金(31760278,32260201);国家卫健委毒品依赖和戒治重点实验室开放课题(2020DAMOP-002)。

摘　　要：目的:探讨利用化学遗传学方法失活海马兴奋性神经元对大鼠氯胺酮(KET)成瘾记忆提取、消退及空间记忆的影响。方法:利用立体定向注射方法向Wistar大鼠海马内注射重组腺相关病毒AAV-CaMKIIα-hM4D(Gi)-EGFP特异感染兴奋性神经元,隔天给KET(15 mg/kg)或生理盐水训练20 d建立条件位置偏爱(CPP)模型;分别在海马背侧(dHPC)、背后侧(pdHPC)或腹侧(vHPC)神经元失活的情况下进行提取,然后消退4 d,检测其CPP分数;在Morris水迷宫任务训练期失活海马神经元,检测动物搜索平台区域的时间和穿越次数。结果:组织学检查表明AAV可感染海马神经元,使胞体及投射到前额叶的轴突末梢表达EGFP;CPP建立后,dHPC、pdHPC或vHPC失活不影响其CPP记忆的提取(P<0.05),并能顺利消退(P>0.05),但其消退记忆的提取受损,KET-CPP恢复(P<0.05);水迷宫任务训练期海马失活动物在测试期搜寻平台区的延迟增加,穿越次数减少(P<0.05)。结论:海马dHPC、pdHPC和vHPC兴奋性神经元均参与空间记忆巩固和KET-CPP成瘾消退记忆提取,海马异常与KET复吸相关。Objective:To investigate the effects of chemogenetic inactivation of hippocampal excitatory neurons on addiction memory retrieval,extinction of ketamine(KET)and spatial memory in rats.Methods:Recombinant adeno-associated virus(AAV)AAV-CaMKⅡα-hM4 D(Gi)-EGFP was used to infect the hippocampal excitatory neurons in Wistar rats,KET(15 mg/kg,i.p.)or saline was treated every other day,and conditioned place preference(CPP)was established after 20 d training.The rats were tested,then were trained(4 d)for CPP extinction underlying neuron inactivation in the dorsal,posterodorsal,or ventral hippocampus(dHPC,pdHPC,or vHPC).At last,Morris water maze task were trained with hippocampal inactivation,and the latency and crossing times for searching the platform field were tested.Results:AAV effectively infected the hippocampal neurons and enhanced green fluorescent protein expressed in local neuron soma and in its axon terminals that project into the prefrontal cortex.After establishment,KET-CPP retrieval(P<0.05)and extinction(P>0.05)could be performed normally by rats with dHPC,pdHPC,or vHPC inactivation,but the followed retrieval of extinction memory was impaired,leading to CPP relapse(P<0.05).In Morris water maze task,the latency for finding the platform field was extended and the crossing times was reduced in rats with hippocampus inactivation during training phase(P<0.05).Conclusion:Excitatory neurons in the three hippocampal subregions(dHPC,pdHPC,esp.vHPC)were all involved in spatial memory consolidation and extinction memory retrieval of KET-CPP,therefore hippocampal abnormalities would be associated with KET addiction relapse.

关 键 词：氯胺酮 条件位置偏爱 记忆 海马 化学遗传学 大鼠 

分 类 号：R749.61[医药卫生—神经病学与精神病学]