目的 基于"趋避冲突理论(the approach-avoid-ance conflict theory)"设计和发明梁氏情境应激箱(Liang's contextual-stress box,Liang's box),旨在诱导小鼠焦虑样行为.该研究主要目的在于,与经典焦虑相关动物行为学测试模型高架十字迷宫(elevated plus maze,EPM)和旷场(open field,OF)相比较,阐明和分析Liang's box优缺点,初步评价其预测效度.方法 Liang's box由1个开放的圆形中央区和3个封闭的长方形外周臂组成.将小鼠分别放入Liang's box、EPM和OF中,令其自由探索15 min,记录、分析和比较3种实验方法的时空数据和行为学指标.小鼠ip给予地西泮(0.5,1.0和2.0 mg·kg-1)和丁螺环酮(0.5,2.0和10 mg·kg-1),研究药物对Liang's box诱导小鼠特征性行为的影响.结果 ①与EPM和OF相比,Liang's box在具有同样简便操作的同时,还具有结构冲突应激强度适中、模型探索面积恰当、区域定义及划分明确、输出数据离散程度小的优势;② Liang's box时空数据涉及7个方面,分别为潜伏期、停留时间、活动路程、运动速度、活动度、不动时间和区间探索.相比之下,时空数据对小鼠行为的评估更加全面;③与EPM和OF相比,Liang's box可以诱导小鼠更多的特征性行为表现,如更多的探索活动、发生更多风险评估行为,并诱发了独特的"家基现象";④因子分析解析了Liang's box诱导小鼠焦虑样状态的7个方面,其中包括一般焦虑、风险评估、向外探索、垂直探索、一般活动、警惕性和家基行为;⑤ 初步评价实验表明:地西泮和丁螺环酮对Liang's box诱导小鼠的特征性行为具有明确的干预作用.结论 作为新型焦虑相关小鼠行为学测试模型,Liang's box在本研究中展现了其在情境应激结构、小鼠行为诱导方面的优势和潜力,并在预测效度评价中具有良好的表现,有望从行为药理学角度为焦虑机制研究和抗焦虑药物筛选工作提供新的方向.

AimsOpioid addiction is a major public health issue, yet its underlying mechanism is still unknown. The aim of this study was to explore the roles of ubiquitin-proteasome system (UPS) and regulator of G protein signaling 4 (RGS4) in morphine-induced behavioral sensitization, a well-recognized animal model of opioid addiction. MethodsWe explored the characteristics of RGS4 protein expression and polyubiquitination in the development of behavioral sensitization induced by a single morphine exposure in rats, and the effect of a selective proteasome inhibitor, lactacystin (LAC), on behavioral sensitization. ResultsPolyubiquitination expression was increased in time-dependent and dose-related fashions during the development of behavioral sensitization, while RGS4 protein expression was not significantly changed during this phase. Stereotaxic administration of LAC into nucleus accumbens (NAc) core inhibited the establishment of behavioral sensitization. ConclusionUPS in NAc core is positively involved in behavioral sensitization induced by a single morphine exposure in rats. Polyubiquitination was observed during the development phase of behavioral sensitization, while RGS4 protein expression was not significantly changed, indicating that other members of RGS family might be substrate proteins in UPS-mediated behavioral sensitization.

Theory predicts that males and females of dioecious species typically engage in an evolutionary sexual conflict over the frequency and choice of mating partner. Female sexual cannibalism, a particularly dramatic illustration of this conflict, is widespread in certain animal taxa including spiders. Nevertheless, females of some funnel weaving spiders that are generally aggressive to conspecifics enter a cataleptic state after male courtship, ensuring the males can mate without risk of attack. In this study, we demonstrated that the physical posture and duration, metabolites, and central neurotransmitters of females of Aterigena aculeata in sexual catalepsy closely resemble females in thanatosis but are distinct from those in anesthesia, indicating that the courted females feign death to eliminate the risk of potentially aggressive responses and thereby allow preferred males to mate. Unlike the taxonomically widespread thanatosis, which generally represents a deceptive visual signal that acts against the interest of the receivers, sexual catalepsy of females in the funnel weaving spiders may deliver a sexual-receptive signal to the courting males and thereby benefit both the signal senders and receivers. Therefore, sexual catalepsy in A. aculeata may not reflect a conflict but rather a confluence of interest between the sexes.

焦虑障碍是当下比较普遍的精神类疾病,其发病机制除了受遗传因素的影响之外,表观遗传学修饰同样发挥了非常关键的调控作用.DNA甲基化是表观遗传修饰的一种重要形式,具有很强的环境敏感性,许多基因在环境应激下的甲基化改变可对焦虑障碍等精神类疾病产生影响.本文主要阐述了糖皮质激素受体基因(NR3C1)、脑源性神经营养因子(BDNF)基因、催产素受体(OX-TR)基因以及神经肽Y(NPY)基因等应激相关基因的甲基化修饰与焦虑障碍之间的密切关联.

Previous studies have indicated a role for molecular chaperone heat shock protein 70 (Hsp70) in the development of behavioural sensitization to morphine in rodents, suggesting that Hsp70 expression following morphine exposure is involved in molecular changes that may underlie addiction vulnerability. The current study was carried out to investigate the role of Hsp70 in the positive reinforcing properties of morphine using conditioned place preference (CPP) in male rats. An unbiased CPP procedure of three phases (pre-conditioning: d1–d3; conditioning: d4–d6; and testing: d7) was used. During the conditioning phase, morphine injections (5 mg/kg, subcutaneously) were administered to induce significant place preference. To explore the effect of Hsp70 on the development and expression of morphine CPP, Hsp70 inhibitors (PES, KNK437 and methylene blue) were administered into the lateral ventricle prior to either morphine conditioning sessions or a morphine challenge on the test day. Furthermore, Hsp70 expression within the mesocorticolimbic system was measured after the treatment with KNK437, a transcriptional inhibitor. We found that PES and KNK437, respectively, injected intracerebroventricularly dose-dependently attenuated both the development and expression of morphine CPP. Methylene blue treatment demonstrated an attenuation of the development, but had no effect on the expression of morphine CPP. Following KNK437 treatment, Hsp70 expression was significantly inhibited in the shell of nucleus accumbens (NAc) during both the development and expression of morphine CPP. The findings suggest that Hsp70 in the NAc shell plays an important role in the reinforcing effects of morphine and may be involved in the development of morphine dependence.

It has previously been demonstrated that neurons immunoreactive for the enzyme adenosine deaminase (ADA) have a highly restricted distribution pattern in the adult rat brain. In order to determine whether the pattern of ADA expression is equally limited during the period of brain development, the localization of ADA was investigated immunohistochemically in brains of embryonic, early postnatal and young adult rats. No immunostaining for ADA was detected on the 12th embryonic day. On embryonic day 15, ADA-immunoreactive cells were first observed in the hypoglossal motor nucleus, and on day 18 in cingulate, retrosplenial and visual cortex, in the posterior basal hypothalamus, and in the facial motor nucleus. On the 20th embryonic day ADA-immunoreactive neurons appeared in various olfactory and related systems and in the superior colliculus. On the 1st postnatal day, immunoreactivity was intensified in all structures in which it was observed at preceeding ages and, in addition, appeared in several brainstem regions. On postnatal day 10 and 15, immunostained neurons appeared in several subcortical structures whereas the number of these decreased in the anterior olfactory nucleus and some related cortical areas. In animals 25 days of age the intensity of immunostaining continued to increase, essentially producing the adult pattern in all except olfactory areas where there was a dramatic loss of ADA-immunoreactive cells. These results show that the restricted pattern of ADA-immunostaining observed in adult rat brain is generated over a protracted period of development, various stages of which are characterized predominantly by the expression of ADA in greater abundance, at least to the extent this can be gleaned immunohistochemically, in greater numbers of neurons and to a minor degree by a decreased capacity to express this enzyme.

目的 建立大鼠和小鼠脑电图头部皮下电极埋置新方法,并检验脑电信号采集的可行性和有效性.方法 采用自行设计改造的颅内电极"头皮包埋式"埋置法,安装大鼠和小鼠头部脑电电极,并考察脑电电极装置的稳定性.用MP150多导生理信号记录仪和脑电数据分析软件SleepSign(版本:3.2.6.1404)采集和分析大鼠和小鼠的脑电信号,比较传统裸露式电极安装法和"头皮包埋式"埋置法采集脑电信号的一致性.用"头皮包埋式"埋置法,采集和比较大鼠和小鼠麻醉和清醒状态时脑电信号特征,观察不同周龄(8,10和12周)对大鼠脑电频率和相对功率的影响.结果 在实验周期内,用传统裸露式电极安装法,大鼠和小鼠头部脑电图装置分别脱落3/10和2/10;"头皮包埋式"埋置法埋置的大鼠和小鼠头部脑电图装置未见脱落,术后切口愈合良好,进食进水及一般行为活动未受明显影响,且该法与传统方法所采集的脑电图相对功率在各频段的分布无显著性差异.用"头皮包埋式"埋置法所采集的脑电信号数据显示,戊巴比妥麻醉的药理作用对大鼠和小鼠各频段相对功率值的影响无统计学差异,但θ,α和β波的相对功率值存在增加的趋势.进一步研究发现,θ,α和β波的相对功率随周龄增加显著升高(P<0.05),而δ波的相对功率无明显变化.结论 "头皮包埋式"埋置法操作简单方便,电极装置更加稳固,保持持久,能够有效采集脑电信号,可在大鼠和小鼠脑电测定相关实验中推广应用.

Background: Accumulating evidence suggest that behavioral sensitization is involved in the process of drug addiction. Zebrafish are sensitive to a variety of addictive drugs and are thus suitable for the study of behavioral sensitization. However, in contrast to mature rodent models of behavioral sensitization, how this phenomenon manifests in aquatic organisms, especially zebrafish, is largely unknown. In this study, we developed a morphineinduced behavioral sensitization adult zebrafish model and performed a preliminary investigation of the underlying mechanisms. Methods: Behavioral sensitization was established in zebrafish by observing their behavior after treatment and challenge with morphine. The effect of morphine was evaluated by a behavioral locomotor test. Different doses of morphine and withdrawal times were used to evaluate the establishment of the behavioral sensitization model. Results: Hyperlocomotion was induced after administration of morphine in adult zebrafish. After withdrawing the drug for a period, challenge with low-dose morphine evoked behavioral sensitization in zebrafish acutely pretreated with morphine. Low-dose morphine failed to induce behavioral sensitization in zebrafish if the withdrawal time was less than 5 days or more than 7 days. Morphine induced behavioral sensitization in zebrafish may involve dopaminergic, glutamatergic and opioid systems. Conclusion: A single low-dose of morphine could induce behavioral sensitization in zebrafish acutely pre-treated with morphine, and this phenomenon was highly correlated with drug dose and withdrawal time. These findings suggest that zebrafish is a suitable model for the study of behavioral sensitization.

Behavioural sensitization (BS) is characterized by enhanced psychomotor responses to a dose of substance of abuse after prior repeated exposure. We previously reported that BS can be induced by a single injection of morphine in rats, whereas septal nuclei are specifically involved in the development phase of BS. Here, we demonstrated that intra-LS or intra-MS microinjections also incubated BS to a systemic morphine injection in a cross-sensitization fashion, whereas inactivation of either subdivision of septal nuclei (LS: lateral septum; MS: medial septum) can negate this ability of morphine. Then, non-selective (naloxone) and selective (μ-, δ- and κ-)opioid receptor antagonists were directly delivered into LS or MS, respectively, ahead of a morphine microinjection, whereas only μ-opioid receptors in both LS and MS play indispensable roles in mediating the BS development. Finally, there was a pronounced elevation in the levels of the monoamines (i.e. dopamine, homovanillic acid, 5-hydroxytryptamine and 5-hydroxyindoleacetic acid) in the septum, 8 h after a morphine injection detected with a HPLC-ECD method, suggesting that dopaminergi and serotoninergic systems are implicated in the BS formation. Our studies demonstrated that septal nuclei critically participate in the BS development. Essentially, μ- instead of δ- or κ-opioid receptors in LS and MS mediate sensitization to opiates.

焦虑障碍是我国成人患病率最高的精神疾病,但其治疗药物的研发却一直滞后于该疾病的医疗需求.目前临床常用的抗焦虑药物主要包括部分苯二氮类药物、非苯二氮类药物和部分抗抑郁药,大多具有令人不快的副作用.该文通过检索Pubmed的文献资料,从内源性大麻素系统、肠-微生物-脑轴和GABAA受体亚基3个角度切入,总结介绍近年新型抗焦虑药物的研究进展,希望能够为该领域的发展提供帮助.

风险评估(RA)是动物针对潜在威胁性刺激演化形成的一种适应性机制,能够帮助动物定位刺激来源、获得刺激相关特征并对潜在危险做出最佳的防御反应.RA过程失调和损害所致的个体表现与焦虑障碍的临床症状相似,并可能与其发病存在直接联系.抗焦虑药物能够显著降低动物模型中RA行为发生的频率,进一步揭示了RA行为与焦虑之间的关系.然而,作为一种可量化的行为学指标,RA虽比传统测量项目对抗焦虑药物检测更灵敏,却很少被采用.本文简要总结了RA行为的功能、神经生物学机制、药理学特征及其在焦虑动物行为学模型中的应用,以期为相关领域的研究提供理论依据.

目的 观察和比较梁氏情境应激箱对小鼠抑郁样行为的诱导作用,对其表观效度进行评价.方法将小鼠放入4种不同应激环境中15 min,随后采用饮糖偏爱实验、社交行为实验、新奇抑制摄食实验以及强迫游泳实验,评价4种情境应激环境对小鼠抑郁样行为相关指标的影响.结果 ①与饲养鼠笼、正方形箱和三角形箱3种情境应激环境相比较,梁氏情境应激箱处理显著性降低ICR小鼠的饮糖偏爱率.此外,间隔3 d重复3次给予梁氏情境应激刺激仍能明显抑制小鼠的饮糖行为;②ICR和KM小鼠属于远交系动物,而C57BL/6J小鼠为近交系动物.梁氏情境应激箱处理对3种小鼠的社交行为均具有明显的抑制作用;③梁氏情境应激箱处理对小鼠新奇抑制摄食实验中进食潜伏期和强迫游泳实验中不动时间未见明显影响.结论梁氏情境应激箱处理可产生特定的情境应激反应,引起小鼠典型的抑郁样行为表现.作为一种新的抑郁动物模型及其实验方法,具有良好的表观效度.

BackgroundAlcohol use disorder places a heavy burden on global public health systems and thus is in urgent need of improved pharmacotherapies. Previously, our group has demonstrated that 30 mg/kg of the indole alkaloid brucine significantly attenuates alcohol‐drinking behavior; however, the high toxicity, poor water solubility, short half‐life, and limited therapeutic window of brucine restrain its clinical application as an antialcoholism medication. We subsequently hypothesized that the oxide of brucine (brucine N‐oxide) would produce a similar behavioral effect without the risk profile associated with brucine.MethodsMale Fawn‐Hooded rats with high innate alcohol preference underwent 2‐bottle choice procedures (Experiments 1 to 3). Experiment 1 examined the effects of 7 daily BNO injections of 0, 30, 50, or 70 mg/kg (s.c.) on voluntary alcohol consumption (n = 9/group). Experiment 2 evaluated the impact of a single dose of 0 or 70 mg/kg BNO on the increased alcohol intake induced by a 4‐day alcohol deprivation (n = 8/group). Experiment 3 tested the effect of 7 daily BNO injections of 0 or 70 mg/kg (s.c.) on sucrose preference (n = 6/group). Experiment 4 measured the median lethal dose (LD50) values of BNO and brucine to compare their acute toxicity in rats. Experiment 5 tested whether BNO (0, 30, 50, and 70 mg/kg, s.c.) affected locomotor activity using an open‐field paradigm (n = 8/group). Finally, Experiment 6 evaluated the possible conditioned rewarding effects of 0, 30, 50, and 70 mg/kg BNO using the conditioned place preference paradigm (n = 6/group).ResultsBNO administration dose‐dependently attenuated alcohol consumption without affecting food intake, total fluid consumption, or the natural preference for a sucrose solution, with 70 mg/kg BNO reducing consumption by 22.8%. A single dose of 70 mg/kg BNO significantly inhibited the alcohol deprivation effect. The LD50 values of BNO and brucine in rats were determined to be 1,103.5 ± 177.0 mg/kg and 264.6 ± 17.7 mg/kg, respectively. Finally, BNO administration did not affect spontaneous locomotor activity or induce a place preference.ConclusionsBNO may help to control excessive alcohol use and should be considered a treatment strategy for future study and development.

The clinical use of opioid analgesics, such as morphine, is limited by analgesic tolerance, molecular mechanism of which is not well understood. Recently, molecular chaperone heat shock protein 70 (Hsp70) has been demonstrated to play important roles in morphine-induced neuroadaptation. Here, we focused on the involvement of Hsp70 in the development of analgesic tolerance to morphine. Rats were treated with morphine (5, 10, 20 mg/kg, subcutaneously) or saline once daily for 10 consecutive days. Hsp70 modulator N-formyl-3, 4-methylenedioxybenzylidine-γ-butyrolactam [KNK437, 100 mg/kg, intraperitoneally (i.p.)], geranylgeranylacetone (500 mg/kg, i.p.) or pifithrin-μ (20 mg/kg, i.p.) was administered before morphine (10 mg/kg, subcutaneously)/saline treatment. Analgesic effect of morphine was measured using the tail-flick latency test, and Hsp70 protein expression was examined by western blot. Analgesic effect of morphine decreased gradually with the increase in the number of days of morphine injection, indicating development of analgesic tolerance. A significant increase of Hsp70 expression in the periaqueductal gray was observed during the development of analgesic tolerance after repeated morphine injections. The development of morphine analgesic tolerance was suppressed by pre-treatment with Hsp70 transcriptional inhibitor KNK437 or functional antagonist pifithrin-μ, while promoted by pre-treatment with Hsp70 transcriptional inducer geranylgeranylacetone. Our results demonstrated that the development of morphine analgesic tolerance was dual regulated by Hsp70 modulators, suggesting Hsp70 as an interesting and new target for preventing the development of opioid analgesic tolerance.

A natural monoterpene alkaloid incarvillateine isolated from the plant Incarvillea sinensis is known to relieve inflammatory and neuropathic pain. However, the molecular target for the action of incarvillateine remains elusive. Here, we report that incarvillateine exacerbates epileptic seizures by inhibiting subtypes of γ-Aminobutyric acid type A (GABAA) receptors. Two-electrode voltage clamp recordings of α1β3γ2, α2β3γ2, α3β3γ2 and α5β3γ2 subtypes expressed in Xenopus oocytes revealed that incarvillateine inhibited the GABAA currents with IC50 of 25.1 μM, 43.1 μM, 105.1 μM and 93.7 μM, respectively. Whole-cell patch clamp recordings of hippocampal slices confirmed that incarvillateine inhibited spontaneous inhibitory postsynaptic currents (IPSCs), and miniature IPSCs and tonic currents. Moreover, inhibition of GABAA currents and spontaneous IPSCs by incarvillateine persisted even in the presence of blockers of adenosine receptors. In addition, incarvillateine enhanced epileptic discharges induced by Mg2+-free artificial cerebrospinal fluid (ACSF) in hippocampal slices. Furthermore, intracerebral ventricular injections of incarvillateine increased the severity of seizures induced by kainic acid in a dose-dependent manner. Taken together, our data demonstrate that incarvillateine aggravates seizures by inhibition of GABAA currents and GABAergic synaptic transmissions.

Background: Urea, the end product of protein metabolism, has been considered to have negligible toxicity for a long time. Our previous study showed a depression phenotype in urea transporter (UT) B knockout mice, which suggests that abnormal urea metabolism may cause depression. The purpose of this study was to determine if urea accumulation in brain is a key factor causing depression using clinical data and animal models. Methods: A meta-analysis was used to identify the relationship between depression and chronic diseases. Functional Magnetic Resonance Imaging (fMRI) brain scans and common biochemical indexes were compared between the patients and healthy controls. We used behavioural tests, electrophysiology, and molecular profiling techniques to investigate the functional role and molecular basis in mouse models. Findings: After performing a meta-analysis, we targeted the relevance between chronic kidney disease (CKD) and depression. In a CKD mouse model and a patient cohort, depression was induced by impairing the medial prefrontal cortex. The enlarged cohort suggested that urea was responsible for depression. In mice, urea was sufficient to induce depression, interrupt long-term potentiation (LTP) and cause loss of synapses in several models. The mTORC1-S6K pathway inhibition was necessary for the effect of urea. Lastly, we identified that the hydrolysate of urea, cyanate, was also involved in this pathophysiology. Interpretation: These data indicate that urea accumulation in brain is an independent factor causing depression, bypassing the psychosocial stress. Urea or cyanate carbamylates mTOR to inhibit the mTORC1-S6K dependent dendritic protein synthesis, inducing impairment of synaptic plasticity in mPFC anddepression-like behaviour. CKD patients may be able to attenuate depression only by strict management of blood urea. (C) 2019 The Authors. Published by Elsevier B.V.

Background Methamphetamine (METH) is a psychostimulant with high abuse liability that affects the monoamine neurotransmitter systems, particularly the dopamine system. Currently there are no effective medications for the treatment of METH abuse to restore METH-induced dopaminergic dysfunction. The Jitai tablet (JTT), a commercial traditional Chinese medicinal preparation, has been shown to modulate the dopaminergic function both in heroin addicts and in morphine-dependent rats. The purpose of this study was to investigate, in a rodent model, whether JTT can protect against METH-induced neurotoxicity, and/or restore METH-damaged dopaminergic function. Methods Immunohistochemical staining and/or autoradiography staining were used to detect tyrosine hydroxylase (TH) expression in the substantia nigra, and to examine the levels of dopamine transporter (DAT), dopamine D2 receptor (D2R) and TH levels in the striatum. Using a stereotyped behavior rating scale, we evaluated the inhibitory effect of JTT on METH-induced behavioral sensitization. Results Repeated METH administration induced obvious stereotyped behavior and neurotoxicity on the dopaminergic system. Pre-treatment with JTT significantly attenuated METH-induced stereotyped responses, and interdicted METH-induced changes in the levels of DAT, D2R and TH expression. Treatment with JTT after METH administration restored DAT, D2R and TH expression to normal levels. Conclusions Our results indicated that JTT protects against METH-induced neurotoxicity and restores the dopaminergic function, and thus might be a potential treatment for the dopaminergic deficits associated with METH abuse.

A single exposure to drugs of abuse is sufficient to induce behavioral sensitization, which is a form of long-lasting neuroplasticity. Dopamine D2 receptors are the main receptor for antipsychotic drugs, but little is known about their role in a single methamphetamine-induced behavioral sensitization. In the present study, we examined whether typical antipsychotic haloperidol and atypical antipsychotic risperidone, both targeting dopamine D2 receptor, could prevent the methamphetamine sensitization when they were given at the different phase of behavioral sensitization. A single methamphetamine exposure induced robust and reliable behavioral sensitization to the lower challenge dose of methamphetamine after 7 days of drug-free period. At doses that did not affect general locomotion, haloperidol and risperidone not only significantly attenuated methamphetamine induced hyperlocomotion, but also completely prevented the development of behavioral sensitization to methamphetamine challenge when they were pretreated before the first exposure to methamphetamine. When haloperidol and risperidone were given in the early period of transfer (2 h after the first methamphetamine exposure), they also dose-dependently attenuated the transfer to expression of methamphetamine sensitization from the hyperlocomotion. These data suggest that dopamine D2 receptors play an important role in methamphetamine sensitization, especially in protecting against the development and transfer in the earlier labile period after the methamphetamine exposure. Therefore, clinically approved dopamine D2 receptor antagonists may be useful in the treatment of methamphetamine addiction.

Substance dependence is a chronic relapsing brain disorder associated with adaptational changes in synaptic plasticity and neuronal functions. The high levels of substance consumption and relapse rate suggest more reliable medications are in need to better address the underlying causes of this disease. It has been well established that the intracellular second messengers cyclic AMP (cAMP) and cyclic GMP (cGMP) and their signaling systems play an important role in the molecular mechanisms of substance taking behaviors. On this basis, the phosphodiesterase (PDE) superfamily, which crucially controls cyclic nucleotide levels by catalyzing their hydrolysis, has been proposed as a novel class of therapeutic targets for substance use disorders. This chapter reviews the expression patterns of PDEs in the brain with regard to neural structures underlying the dependent process and highlights available evidence for a modulatory role of PDEs in substance dependence.

Withdrawal symptoms stand as a core feature of alcohol dependence. Our previous results have shown that inhibition of phosphodiesterase-4 (PDE4) decreased ethanol seeking and drinking in alcohol-preferring rodents. However, little is known about whether PDE4 is involved in ethanol abstinence-related behavior.