慢性吗啡给予、戒断及再给药过程中大鼠海马感觉门控的动态变化

药物成瘾被认为是药物长期作用于脑而产生的一种慢性复吸性脑疾病,长期反复的药物（如吗啡）滥用会导致一系列严重后果,如药物依赖、药物耐受、强迫性药物寻求等。本实验利用条件化位置偏好（conditioned place preference,CPP）模型来检测大鼠对吗啡依赖和心理渴求等过程;采用双声刺激听觉诱发电位来研究大鼠在慢性吗啡给予、戒断以及再给药过程中海马感觉门控（N40）的动态变化。吗啡组大鼠注射吗啡（10mg／kg,i．p．）12d,经历第一次戒断12d,再次注射吗啡（2．5mg／kg,i．P．）1d,之后经历第二次戒断2d;对照组大鼠注射同体积生理盐水,其余实验条件与吗啡组相同。CPP实验表明,这种药物给予方法促使大鼠对吗啡产生药物依赖和心理渴求。双声刺激诱发电位实验表明,吗啡组大鼠在吗啡给予期间海马感觉门控受到损伤;第一次戒断期的第1～2天海马感觉门控能力减弱,第3天增强,第4～12天逐渐恢复到正常水平;再次给予吗啡后海马感觉门控能力与对照组相比显著降低,并且随后2d的戒断期内海马感觉门控能力也一直保持较低水平,表明再次给药使大鼠海马感觉门控对吗啡更加敏感化。结果提示,长期反复的吗啡给予及再给药干扰了海马的感觉门控能力,吗啡成瘾对大脑可能产生长期影响。     

中央杏仁核中促肾上腺皮质激素释放激素神经元调控吗啡戒断诱发的负性情绪北大核心CSCD

成瘾药物戒断诱发负性情绪并伴有脑内应激系统的激活,是导致负性强化并使成瘾个体持续觅药和复吸的重要因素。促肾上腺皮质激素释放激素(corticotrophin-releasing hormone, CRH)是应激系统发挥生理作用的重要递质,在介导焦虑、恐惧等负性情绪的重要核团--中央杏仁核(central amygdala, Ce A)中广泛分布。然而在Ce A中这类表达CRH的神经元在成瘾药物戒断引发的负性情绪中作用还并不清楚。本研究采用CRH-Cre转基因小鼠,通过依赖Cre-Lox P系统的化学遗传学方法特异性激活或抑制小鼠Ce A中的CRH神经元,结合条件性位置厌恶(conditioned place aversion, CPA)、高架十字迷宫、自主活动能力测试等行为学实验,探究Ce A中CRH神经元对小鼠吗啡戒断产生的厌恶、焦虑等负性情绪的影响。结果显示,抑制Ce A中CRH神经元可抑制小鼠吗啡戒断诱导的CPA形成,并降低小鼠焦虑水平。直接激活Ce A中CRH神经元可使未经历吗啡暴露的小鼠产生CPA和焦虑。吗啡自然戒断和CRH神经元的活性改变对小鼠的自主活动能力都没有显著影响。以上结果提示,Ce A中CRH神经元参与调控小鼠吗啡戒断诱导的负性情绪。本研究为药物成瘾与复吸机制提供了理论依据。     

磁场对小鼠两种迷宫学习记忆的影响

据发现,磁场对生物体有一定作用,但是磁场对于人类或实验动物的学习记忆是否有影响,目前的报道结果很不一致。本实验采用实验小白鼠,给予不同强度（65高斯／50Hz,35高斯/25Hz）的低频磁场照射（每天1小时,持续25天）。磁场照射后,采用旷场行为测试、Y-迷宫和Morris水迷宫,检测小鼠的活动性、空间辨别、空间学习记忆和非空间学习记忆能力。结果表明：65高斯／50Hz磁场显著增高小鼠的活动性,并损伤小鼠Y-迷宫的空间辨别能力,但对Morris水迷宫的空间、非空间学习记忆无明显影响。35高斯／25Hz磁场处理动物行为在三个指标上均接近对照组。提示：长期的磁场照射可能会给动物,甚至人类造成一些影响。     

阿片μ受体介导应激诱发的空间参考记忆损伤

学习记忆障碍是应激后最严重的问题之一,其确切的机制有待阐明。内源性阿片系统对包括学习记忆在内的多种生理功能具有重要调控作用,而该系统是否参与应激后学习记忆功能的损伤尚未明确。本研究旨在探讨阿片μ受体在应激诱发的学习记忆障碍中的作用。以昆明小鼠为研究对象,进行连续4天的Morris水迷宫训练,每天水迷宫训练前高台应激30min,并在侧脑室注射生理盐水、阿片μ受体特异性激动剂DAMGO或阿片μ受体特异性拮抗剂CTAP,第五天测试小鼠空间参考记忆能力。结果显示,水迷宫训练前激活μ受体可损伤小鼠空间参考记忆能力,而阻断μ受体对小鼠空间参考记忆能力没有影响;训练前进行30 min的高台应激处理可以损伤小鼠空间参考记忆提取能力;在高台应激后立即向侧脑室注射μ受体激动剂DAMGO可以加重小鼠空间学习记忆能力的损伤,但注射μ受体阻断剂CTAP可以翻转高台应激对小鼠空间参考记忆能力的损伤效应。以上结果提示,应激状态下,内源性阿片μ受体系统参与调控小鼠空间参考记忆能力的损伤效应。     

芋螺多肽及其突变体对小鼠吗啡身体依赖发展的抑制作用

目的:评价N-甲基-D-天冬氨酸(NMDA)受体抑制剂芋螺多肽Con-G、Con-T及其突变体对小鼠吗啡身体依赖发展的抑制作用。方法:每天8:30和16:30在小鼠皮下注射吗啡30mg/kg,连续3d,形成吗啡身体依赖模型;第1d和第3d16:30给完吗啡30min后,侧脑室给予15nmol/kg的Con-G、Con-T或其突变体;第4d8:30注射纳洛酮催促戒断,测定小鼠10min内的跳跃次数。结果:Con-G突变体中,Con-G[S16Y]抑制小鼠吗啡身体依赖发展的活性显著提高,Con-G[Q6A]活性与Con-G相似,Con-G[N8A]和Con-G[γ14A]无活性,Con-G[γ10K]活性较弱。Con-T突变体中,Con-T[M8I]、Con-T[M8A]抑制小鼠吗啡身体依赖发展及急性戒断活性活性最强,Con-T[R13A]、Con-T[γ14A]、Con-T[M8F]及Con-T[M8N]有明显活性,Con-T[L9A]和Con-T[γ10A]活性低。结论:一些Con-G及Con-T突变体对小鼠吗啡身体依赖发展具有很强的活性,活性强弱与其对NMDA受体NR2B的活性及选择性相关。     

青藤碱对吗啡依赖与戒断小鼠小脑与脊髓NO/nNOS系统的影响

本文旨在探讨青藤碱对吗啡依赖与戒断小鼠的小脑和胸腰段脊髓中一氧化氮（nitric oxide,NO）／神经元型一氧化氮合酶（neural nitric oxide synthase,nNOS）系统的影响及作用机制。采用吗啡剂量递增法建立小鼠吗啡依赖模型,用纳洛酮激发戒断症状,评价小鼠急性戒断时齿颤、扭体、直立、喷嚏、眼睑下垂等戒断症状,对成瘾小鼠用青藤碱（40mg／kg,i．P．）治疗后,再用纳洛酮激发观察戒断症状。半定量RT—PCR检测小鼠小脑和胸腰段脊髓nNOS mRNA表达变化,化学比色法和硝酸还原酶法分别测定小鼠小脑和胸腰段脊髓组织匀浆的nNOS活性与NO含量。结果显示：（1）青藤碱可以扭转由吗啡依赖引起的小鼠体重下降的趋势,减轻小鼠急性戒断时齿颤、扭体、直立、喷嚏、眼睑下垂等戒断症状;（2）青藤碱可降低小鼠吗啡依赖与戒断时在小脑与胸腰段脊髓中异常上调的nNOS mRNA水平,使酶活性下降到接近对照组水平。nNOS催化产生的NO含量与酶活性的变化一致;（3）单独使用青藤碱,小鼠没有出现类似吗啡引起的戒断症状,小脑与胸腰段脊髓中nNOS mRNA水平及酶活性没有异常升高。上述结果表明,青藤碱本身无成瘾性,但能显著减轻吗啡依赖小鼠的戒断征状,其作用机制可能与青藤碱影响小脑与脊髓中的NO／nNOS系统有关。     

慢性吗啡处理及戒断对社会新颖性和食物寻求行为的影响（英文）

阿片肽在调控社会性和非社会性天然奖赏中具有重要作用。寻求天然奖赏的动机与动物的情绪状态有关。吗啡注射和戒断会引起动物不同的情绪状态。本研究探讨了吗啡处理期和戒断期是否会影响动物对2种类型天然奖赏(社会新颖性和食物)的寻求行为。雄性小鼠连续注射14 d的吗啡(10 mg·kg~(-1),生理盐水作对照组),在最后一次注射20 min后,依次检测了小鼠的运动性及对熟悉个体、陌生个体和食物的接近时间。戒断7 d后,以上行为变量(除运动性)被再次检测。结果表明,盐水处理及戒断的小鼠对陌生个体的接近时间明显多于熟悉个体,且表现出对食物的偏好。吗啡处理的小鼠运动性增加,接近陌生个体和熟悉个体的时间差异无统计学意义,但仍表现出对食物的偏好。与盐水组相比,吗啡戒断降低了小鼠对食物的偏好,但不影响对陌生个体的接近时间。这些结果表明,吗啡会损害寻求社会新颖性和食物的动机;慢性吗啡处理和戒断对这2种天然奖赏的寻求行为有不同的影响,这种差异可能与吗啡经验诱导的不同神经适应有关。     

梓醇对鱼藤酮损伤小鼠的记忆、抗氧化能力的影响及安全性评价

目的:研究梓醇对鱼藤酮损伤小鼠的学习记忆能力及皮层抗氧化系统的影响,并对其安全性进行评价.方法:腹腔注射鱼藤酮建立小鼠皮层抗氧化系统损伤模型,腹腔注射给药21 d后进行Y迷宫试验,再测定各组小鼠皮层谷胱甘肽过氧化物酶(GSH-PX)、谷胱甘肽S-转移酶(GST)、丙二酫(MDA)、谷胱甘肽(GSH)水平;梓醇安全性评价采取小鼠急性毒性试验和大鼠长期毒性试验.结果:梓醇能够改善小鼠的迷宫成绩,增强GSH-PX活性和GSH含量,降低GST活性和MDA含量,抑制LDH的释放.小鼠腹腔注射给药梓醇的LD50为206.5mg/kg.;大鼠尾静脉注射90天,未见动物出现血液学、血液生化及主要脏器的毒性变化.结论:梓醇能改善鱼藤酮损伤小鼠的记忆能力,减轻皮层氧化应激损伤;长期使用无明显的毒副作用.     

吗啡和胆碱能拮抗剂联合给药对小鼠Y迷宫空间记忆提取及活动性的影响(英文）

吗啡和胆碱能系统的相互作用已在多项研究中提到,本实验想查明吗啡是否能和胆碱能拮抗剂、东莨菪碱以及阿托品共同作用对小鼠的Y迷宫空间识别记忆提取产生影响。采用测试前腹腔给药的方法,选用3种剂量的吗啡(5、1.5、0.5mg/kg),两种剂量的东莨菪碱(1、0.1mg/kg),以及两种剂量的阿托品(0.5、0.1mg/kg),剂量由高到低相配对作为联合给药的手段。其结果表明:1)0.5mg/kg低剂量吗啡与0.1mg/kg低剂量的东莨菪碱,或与0.1mg/kg低剂量的阿托品联合给药的小鼠,在记忆提取测试中,空间探查行为(各臂停留时间百分比)对新异臂没有偏好,而新奇探索行为(各臂访问次数百分比)仍保持了对新异臂的偏好,而相应剂量药物单独给药的小鼠记忆提取均没有被损害;2)吗啡能和东莨菪碱相互作用使小鼠的活动性显著增强。暗示吗啡和胆碱能拮抗剂对小鼠空间记忆提取的破坏存在一定程度的相互作用。     

青藤碱对吗啡依赖与戒断小鼠脑组织nNOS活性的影响

目的:观察青藤碱对吗啡依赖与戒断小鼠中枢神经系统中大脑皮层、小脑、脑干的nNOS活性变化的影响。方法:剂量递增法建立小鼠吗啡依赖模型,青藤碱治疗前后用纳洛酮催瘾,观察戒断症状;化学比色法测各脑组织匀浆的nNOS活性。结果:青藤碱可扭转成瘾小鼠的体重下降趋势,减轻戒断症状;使由吗啡依赖与戒断引起异常变化的nNOS活性水平恢复到最终接近对照组水平。结论:青藤碱能显著减轻吗啡依赖小鼠的戒断征状,其机制可能与青藤碱影响各脑组织nNOS活性相关。     

Short- and long-term cognitive effects of chronic cannabinoids administration in late-adolescence rats

The use of cannabis can impair cognitive function, especially short-term memory. A controversial question is whether long-term cannabis use during the late-adolescence period can cause irreversible deficits in higher brain function that persist after drug use stops. In order to examine the short- and long-term effects of chronic exposure to cannabinoids, rats were administered chronic i.p. treatment with the CB1/CB2 receptor agonist WIN55,212-2 (WIN; 1.2 mg/kg) for two weeks during the late adolescence period (post-natal days 45-60) and tested for behavioral and electrophysiological measures of cognitive performance 24 hrs, 10 and 30 days after the last drug injection. The impairing effects of chronic WIN on short-term memory in the water maze and the object recognition tasks as well as long-term potentiation (LTP) in the ventral subiculum (vSub)-nucleus accumbens (NAc) pathway were temporary as they lasted only 24 h or 10 d after withdrawal. However, chronic WIN significantly impaired hippocampal dependent short-term memory measured in the object location task 24 hrs, 10, 30, and 75 days after the last drug injection. Our findings suggest that some forms of hippocampal-dependent short-term memory are sensitive to chronic cannabinoid administration but other cognitive impairments are temporary and probably result from a residue of cannabinoids in the brain or acute withdrawal effects from cannabinoids. Understanding the effects of cannabinoids on cognitive function may provide us with tools to overcome these impairments and for cannabinoids to be more favorably considered for clinical use.     

Depression of Mesolimbic Dopamine Transmission and Sensitization to Morphine During Opiate Abstinence

To investigate the role of mesolimbic dopamine (DA) in the mechanism of drug dependence, extracellular DA was monitored by transcerebral dialysis in the caudal nucleus accumbens under basal conditions and after challenge with morphine (5 mg/kg s.c.) in control rats and in rats made dependent on and then deprived of morphine. Withdrawal from morphine resulted in a marked reduction of extracellular DA concentrations from control values at 1, 2, 3, and 5 days of withdrawal. After 7 days of withdrawal, DA output was less, but still significantly, reduced. Challenge with morphine resulted in stimulation of DA output in controls (maximum, 35%), no effect on the first day of withdrawal, and stimulation similar to controls' on days 2 and 7 of withdrawal. On day 5 and, particularly, on day 3 of withdrawal, morphine-induced stimulation of DA output was markedly potentiated (maximum, 100 and 160%, respectively). Changes in the sensitivity of DA transmission to morphine challenge were associated with changes in the behavioral stimulant effects of morphine, with tolerance on day 1 and marked sensitization on days 3 and 5 but also on day 7, when morphine-induced stimulation of transmission was no longer potentiated. The results indicate that repeated morphine administration induces a state of dependence in DA neurons and a short-lasting tolerance followed by an increased sensitivity to its stimulant effects on DA transmission. These changes might play an important role in the development of opiate addiction and in the maintenance of opiate self-administration in dependent subjects.     

Expression changes of hippocampal energy metabolism enzymes contribute to behavioural abnormalities during chronic morphine treatment

Dependence and impairment of learning and memory are two well-established features caused by abused drugs such as opioids. The hippocampus is an important region associated with both drug dependence and learning and memory. However, the molecular events in hippocampus following exposure to abused drugs such as opioids are not well understood. Here we examined the effect of chronic morphine treatment on hippocampal protein expression by proteomic analyses. We found that chronic exposure of mice to morphine for 10 days produced robust morphine withdrawal jumping and memory impairment, and also resulted in a significant downregulation of hippocampal protein levels of three metabolic enzymes, including Fe-S protein 1 of NADH dehydrogenase, dihydrolipoamide acetyltransferase or E2 component of the pyruvate dehydrogenase complex and lactate dehydrogenase 2. Further real-time quantitative PCR analyses confirmed that the levels of the corresponding mRNAs were also remarkably reduced. Consistent with these findings, lower ATP levels and an impaired ability to convert glucose into ATP were also observed in the hippocampus of chronically treated mice. Opioid antagonist naltrexone administrated concomitantly with morphine significantly suppressed morphine withdrawal jumping and reversed the downregulation of these proteins. Acute exposure to morphine also produced robust morphine withdrawal jumping and significant memory impairment, but failed to decrease the expression of these three proteins. Intrahippocampal injection of D-glucose before morphine administration significantly enhanced ATP levels and suppressed morphine withdrawal jumping and memory impairment in acute morphine-treated but not in chronic morphine-treated mice. Intraperitoneal injection of high dose of D-glucose shows a similar effect on morphine-induced withdrawal jumping as the central treatment. Taken together, our results suggest that reduced expression of the three metabolic enzymes in the hippocampus as a result of chronic morphine treatment contributes to the development of drug-induced symptoms such as morphine withdrawal jumping and memory impairment.     

Mice with Deficient BK Channel Function Show Impaired Prepulse Inhibition and Spatial Learning,but Normal Working and Spatial Reference Memory

Genetic variations in the large-conductance, voltage- and calcium activated potassium channels (BK channels) have been recently implicated in mental retardation, autism and schizophrenia which all come along with severe cognitive impairments. In the present study we investigate the effects of functional BK channel deletion on cognition using a genetic mouse model with a knock-out of the gene for the pore forming α-subunit of the channel. We tested the F1 generation of a hybrid SV129/C57BL6 mouse line in which the slo1 gene was deleted in both parent strains.We first evaluated hearing and motor function to establish the suitability of this model for cognitive testing. Auditory brain stem responses to click stimuli showed no threshold differences between knockout mice and their wild-type littermates. Despite of muscular tremor, reduced grip force, and impaired gait, knockout mice exhibited normal locomotion. These findings allowed for testing of sensorimotor gating using the acoustic startle reflex, as well as of working memory, spatial learning and memory in the Y-maze and the Morris water maze, respectively.Prepulse inhibition on the first day of testing was normal, but the knockout mice did not improve over the days of testing as their wild-type littermates did. Spontaneous alternation in the y-maze was normal as well, suggesting that the BK channel knock-out does not impair working memory. In the Morris water maze knock-out mice showed significantly slower acquisition of the task, but normal memory once the task was learned. Thus, we propose a crucial role of the BK channels in learning, but not in memory storage or recollection.     

慢性吗啡依赖树鼩模型的建立

吗啡是一种有效的镇痛药,但易使动物产生耐受性和成瘾性。在该实验中,中缅树鼩(Tupai a belangeri chinensis)连续7d,每天接受三次肌肉注射递增剂量(5、10、15、20mg/kg体重)吗啡后对吗啡产生耐受和依赖;吗啡注射完成后,腹腔注射纳洛酮(1.25mg/kg体重)催瘾,可诱导其条件性位置厌恶(conditioned place aversion,CPA)及相应吗啡戒断症状的出现。该结果提示树鼩慢性吗啡依赖模型的建立可用于研究吗啡依赖和耐受的生物学机制,以及减轻戒断症状药物的筛选。     

Transgenic expression of androgen receptors improves spatial memory retention in both sham-irradiated and 137Cs gamma-irradiated female mice

Using a water maze, it has been shown that both wild-type and apoE4-expressing female mice are at greater risk of developing age-related hippocampal-dependent impairments in spatial learning and memory than age-matched male mice of the same genotype. In addition, apoE4-expressing female mice were more sensitive to 137Cs gamma-radiation-induced impairment in spatial learning and memory than age-matched male mice of the same genotype. These findings imply that androgen receptors (ARs) contribute to spatial learning and memory, posing the question as to whether transgenic expression of AR in female mice might modulate hippocampal-dependent learning and memory under baseline conditions and after local brain irradiation. Hippocampal-dependent novel location recognition was comparable in wild-type and AR-Tg female mice. This function was impaired after irradiation in AR-Tg but not wild-type mice. In contrast, sham-irradiated wild-type and AR-Tg female mice showed hippocampal-independent novel location recognition, and this was not affected by radiation. After the second day of hidden platform training, in a water maze probe trial, sham-irradiated and irradiated AR-Tg female mice showed spatial memory retention but irradiated wild-type mice did not. After the third day of hidden platform training, only irradiated wild-type female mice did not show spatial memory retention in the water maze probe trial. Both sham-irradiated and irradiated wild-type and AR-Tg female mice showed passive avoidance learning and memory. These data support an important role for AR in spatial memory retention in water maze probe trials in female mice under baseline conditions and after cranial irradiation.     

CCK-8 Inhibits Acute Morphine-induced Spatial Reference Memory Impairment in Mice

Administration of morphine may impair learning and memory processes. Cholecystokinin has been reported to be involved in various types of memory, and our previous study found that Cholecystokinin octapeptide attenuates spatial memory impairment in chronic morphine-treated mice. However, the effect of CCK-8 on acute morphine-induced memory impairment is not clear. In this study, effect of acute CCK-8 and morphine on spatial reference memory was evaluated using Morris water maze in KM mice. Acetylcholine (Ach) content was measured using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC–MS/MS). Pre-training with morphine (5, 10 mg/kg, i.p.) significantly impaired spatial reference memory acquisition without disturbing the performance in the visible platform task, while pre-test morphine has no effect on memory retrieval. Pre-training (0.01, 0.1 and 1 μg, i.c.v.) or pre-test (0.1 and 1 μg, i.c.v.) of CCK-8 facilitated spatial reference memory acquisition and retrieval, respectively. CCK-8 (0.1 and 1 μg) significantly attenuated memory loss by pre-training morphine. Furthermore, CCK-8 (1 μg, i.c.v) increased acetylcholine contents of hippocampus in saline or morphine-treated mice. Our study identifies CCK-8 reversed spatial reference memory loss induced by acute morphine, and the mnemonic effect could be related to the facilitation of CCK-8 on memory acquisition and retrieval through accelerating acetylcholine release in hippocampus.     

Cognitive Impairments Accompanying Rodent Mild Traumatic Brain Injury Involve p53-Dependent Neuronal Cell Death and Are Ameliorated by the Tetrahydrobenzothiazole PFT-α

With parallels to concussive mild traumatic brain injury (mTBI) occurring in humans, anesthetized mice subjected to a single 30 g weight drop mTBI event to the right parietal cortex exhibited significant diffuse neuronal degeneration that was accompanied by delayed impairments in recognition and spatial memory. To elucidate the involvement of reversible p53-dependent apoptosis in this neuronal loss and associated cognitive deficits, mice were subjected to experimental mTBI followed by the systemic administration of the tetrahydrobenzothiazole p53 inactivator, PFT-α, or vehicle. Neuronal loss was quantified immunohistochemically at 72 hr. post-injury by the use of fluoro-Jade B and NeuN within the dentate gyrus on both sides of the brain, and recognition and spatial memory were assessed by novel object recognition and Y-maze paradigms at 7 and 30 days post injury. Systemic administration of a single dose of PFT-α 1 hr. post-injury significantly ameliorated both neuronal cell death and cognitive impairments, which were no different from sham control animals. Cellular studies on human SH-SY5Y cells and rat primary neurons challenged with glutamate excitotoxicity and H₂O₂ induced oxidative stress, confirmed the ability of PFT-α and a close analog to protect against these TBI associated mechanisms mediating neuronal loss. These studies suggest that p53-dependent apoptotic mechanisms underpin the neuronal and cognitive losses accompanying mTBI, and that these are potentially reversible by p53 inactivation.     

Valproate Improves Memory Deficits in an Alzheimer’s disease Mouse Model: Investigation of Possible Mechanisms of Action

Alzheimer’s disease (AD) is a very common progressive neurodegenerative disorder affecting the learning and memory abilities in the brain. Key findings from recent studies of epigenetic mechanisms of memory suggest chromatin remodeling disorders via histone hypoacetylation of the lysine residue contribute to the cognitive impairment in AD. Therefore, the deinhibition of histone acetylation induced by histone deacetylases (HDACs) inhibitors contributes to recovery of learning and memory. We show here that the antiepileptic drug sodium valproate (VPA) potently enhanced long-term recognition memory and spatial learning and memory in AD transgenic mice. Possible mechanisms showed VPA could significantly elevate histone acetylation through HDACs activity inhibition and increase plasticity-associated gene expression within the hippocampi of mice. Our study suggests that VPA, serving as a HDACs inhibitor, can be considered as a potential pharmaceutical agent for the improvement of cognitive function in AD.