摘要
慢性应激能够影响学习和记忆等认知功能。海马和额叶是与学习和记忆联系密切的脑区,参与信息的获得、保持及提取。碱性成纤维生长因子(FGF2)对神经元发生、存活以及损伤修复具有重要促进作用,目前成为神经系统退行性疾病相关研究的热点。本研究旨在探索慢性应激如何影响大鼠学习和记忆能力,以及这一过程中FGF2蛋白在海马和额叶中表达的改变。实验中将16只雄性SD大鼠随机分为对照组和慢性应激组,采用慢性不可预见温和刺激建立大鼠慢性应激模型,通过Morris水迷宫实验及Y迷宫实验检测学习与记忆功能的改变,并对海马及额叶中FGF2蛋白的表达情况进行Western blot及免疫组织化学检测。结果发现,5周慢性应激导致大鼠学习和记忆能力受损,海马及额叶FGF2蛋白表达下调。因此认为,FGF2蛋白可能参与慢性应激损害学习记忆能力的机制,提示FGF2可能是诊断和治疗神经系统退行性病变的分子靶目标。
It is well documented that chronic stress can produce cognitive impairment, and that the hippocampus and prefrontal cortex play an important role in the process of learning and memory. The present study investigated the effects of chronic stress through examination of the modulation tone of FGF2 protein in hippocampus and prefrontal cortex. The fibroblast growth factor-2 （FGF2）, a mitogen that is involved in brain development and regeneration, has been shown to facilitate neurogenesis and synaptic plasticity, as well as be involved in the mechanism of neurodegenerative disorders.
In the experiment, sixteen male Sprague-Dawley rats were randomly assigned into control group and stress group and the chronic unpredictable mild stress （CUMS） model was performed to construct chronic stress model of rats. The stress group received 35 days CUMS which were consisted of food deprivation, water deprivation, clip tail, feet shock, forced swimming in cold water, wet bedding, and disturbed light-dark cycle. Following the last stressor, stressed and non-stressed rats began training in the Morris Water Maze （MWM） and Y Maze to test the change of the ability of learning and memory about space clue fixed position and conditioned escape response. The changes of protein level of FGF2 in hippocampus and prefrontal cortex were observed by Western blot analysis and Immunohistochemistry analysis.
Compared with the rats of control group, the rats of stress group have obvious impairments in learning and memory. In the MWM, the rats exposed to stress had longer latencies to reach the hidden platform during training phase （p〈0.01）, and passed fewer times through the platform location （p〈0.01）. In the Y maze test, stressed rats needed more learning performances （p〈0.05） and had less precision rate （p〈0.05）. The protein level of FGF2 was downregulated in hippocampus of rats （p〈0.001）, especially the dentate gyrus, CA1 neurons and CA3 pyramidal neurons. The same changes also happened in prefrontal
出处
《心理学报》
CSSCI
CSCD
北大核心
2011年第7期784-791,共8页
Acta Psychologica Sinica
关键词
FGF2
慢性应激
学习记忆
海马
额叶
FGF2
chronic stress
learning and memory
hippocampus
prefrontal cortex
