“Y型迷宫在中学的应用”一节选修课教学设计

在"Y型迷宫在中学的应用"一节选修课教学中,借助Y型迷宫,以小鼠为实验对象,设置不同刺激源,用秒表记录被试鼠在每个迷宫臂内的时间,探究其气味偏好,再展开系列问题教学。在实验教学过程中,学生主动参与实验设计和操作,有利于培养其科研能力和创新思维能力。     

脑心通对急性低压低氧小鼠空间记忆功能及脑水肿的影响

目的:探讨脑心通对急性低压低氧诱发的空间记忆功能损害及脑水肿的预防作用及机制。方法:144只小鼠随机分为6组:即常压常氧组、常压常氧给药组、模拟海拔4km组(4km组)、模拟海拔8km组(8km组)、模拟海拔4km给药组(4km给药组)、模拟海拔8km给药组(8km给药组)。比较各组实验前后及组间的Y型电迷宫测试成绩及脑组织水含量、伊文思兰(EB)含量。结果:各组实验前的Y型电迷宫训练成绩无显著差异,实验后常压常氧组、常压常氧给药组、4km组、4km给药组、8km组和8km给药组,Y型电迷宫测试成绩分别为90.00±6.32、93.33±5.16、56.67±8.16、86.67±8.16、45.00±10.49和85.00±5.48(P<0.01);常压常氧组、常压常氧给药组、4km组、4km给药组、8km组和8km给药组比较,脑组织水含量结果分别为77.79±0.27、77.66±0.23、78.42±0.18、77.81±0.18、79.04±0.33、77.94±0.42,EB含量结果分别为0.44±0.04、0.43±0.02、0.98±0.07、0.46±0.06、1.17±0.07、0.49±0...     

小鼠T型迷宫空间学习模型的建立和教学拓展研究

通过拓展性实验研究,建立小鼠T型迷宫空间学习模型。采用T型迷宫,分别进行食物(A臂)和电(B臂)刺激,观察小鼠进入A臂和B臂的次数百分比以研究小鼠空间学习模型,并采用问卷调查方法评估教学质量。电刺激后随着时间推移小鼠进入A臂次数的百分比逐渐增高,第5天小鼠进入A臂的次数百分比为95%,明显高于第1天(45%)。通过问卷调查,实验满意度为98.11%。通过拓展性实验研究,成功建立小鼠空间学习模型,取得较好的教学效果。     

短尾蝮操作性条件反射训练探究

操作性条件反射训练是研究动物认知行为的重要方法,目前这一方法在经典模式动物中的应用较成熟,但在蛇类等爬行动物上鲜有报道。蝮亚科Crotalinae蛇类特有的红外感知觉系统受到了动物学、神经生物学和仿生学研究的关注,有效的操作性条件反射训练是揭示生物红外成像机制的关键方法。本实验以短尾蝮Gloydius brevicaudus为被试动物,采用Y迷宫考察了操作性条件反射训练的3种惩罚刺激方案。训练结果表明,水、高温、敲击刺激均不能使短尾蝮学会将Y迷宫路径选择与目标信号进行稳定关联。研究证明,基于现有惩罚刺激的训练方案对短尾蝮的条件反射习得效果弱于既有研究的其他实验动物。     

通脉益智方对VD大鼠学习记忆行为和海马CA1区突触结构的影响

目的:观察通脉益智方对血管性痴呆模型大鼠学习记忆行为和海马CA1区突触超微结构的影响.方法:应用高脂血症大鼠,采用脑缺血再灌注的方法建立血管性痴呆动物模型,利用跳台实验和Y型迷宫实验检验大鼠的学习记忆能力,应用透射电镜和光镜观察分析海马CA1区神经细胞和突触形态结构的变化.结果:跳台实验和Y型迷宫实验表明模型大鼠学习记忆能力明显下降,而给予通脉益智方组学习记忆能力改善,与模型组相比有显著性差异(p＜0.05).形态学观察显示模型组大鼠海马CA1区神经细胞排列紊乱,核固缩、退化、变性、坏死、消失.突触结构不完整,突触小泡减少;突触间隙模糊,线粒体肿胀、空泡样变.通脉益智方组的神经细胞、突触的形态与模型组相比有明显改善.结论:通脉益智方通过减轻突触的损伤及对神经细胞的保护作用,从而改善了学习记忆能力.     

多靶点抗AD bis-MEP-乙二酰胺杂合物ZLA抑制神经元型AChE活性及促智作用研究

目的:探究ZLA对神经元型AChE的抑制活性及其对中枢胆碱能神经功能障碍导致的学习记忆功能减退的改善作用。方法:通过体外实验观察ZLA对神经元型AChE活性的影响;通过ex vivo实验观察ZLA体内AChE抑制活性;利用Morris水迷宫行为学实验探讨ZLA对东莨菪碱诱发的小鼠学习记忆功能障碍的改善作用。结果:ZLA明显抑制人SH-SY5Y神经元细胞和小鼠海马神经元来源的AChE活性。另外,ZLA腹腔注射后以剂量依赖性方式抑制小鼠脑内AChE活性。Morris水迷宫实验结果显示,ZLA显著改善东莨菪碱引起的学习和记忆功能障碍。结论:ZLA能够抑制神经元型AChE活性并具有促智作用。     

12T强静磁场对小鼠前庭系统及学习记忆能力的影响

目的:随着强静磁场的广泛应用,其生物安全性评估获得越来越多的关注。本文通过实验,评估强静磁场照射对小鼠前庭系统、学习记忆能力的影响及两者内在联系。方法:观察12T强静磁场照射2h条件下小鼠即时(2min内)效应和条件味觉厌恶反应情况,确定照射对小鼠前庭系统的影响;通过Y迷宫和Morris水迷宫实验,分析照射对小鼠学习记忆能力的影响。结果:研究发现照射后小鼠立即出现直立行为抑制、旋转平衡失调,以及持续10d的条件味觉厌恶反应,表明该照射对小鼠前庭系统造成了即时及持续影响。Y迷宫和Morris水迷宫分析结果表明照射后小鼠学习记忆能力未发生显著改变。结论:12T强静磁场2h照射对小鼠前庭系统存在显著影响和量效关系,照射可导致小鼠出现平衡失调,持续味觉厌恶的现象,但这种影响并非结构性或不可逆的,对小鼠学习记忆能力未造成影响。     

人参皂苷Rg2抗MTD大鼠海马神经元凋亡的研究

目的:观察多发梗塞性痴呆模型大鼠CPU凋亡相关蛋白的改变,研究其在学习记忆障碍中的作用机制,并探讨人参皂苷Rg2的干预作用。方法:将复合血栓诱导剂经大鼠左颈总-颈内动脉注射入其左侧大脑半球,诱导半球内血栓形成,造成多发梗塞,从而建立大鼠的学习和记忆功能障碍模型。分别给予不同剂量的人参皂苷Rg2治疗7天,并以尼莫地平进行对照。用Y型电迷宫检测正常对照及痴呆模型大鼠学习和记忆能力的改变;对大鼠的脑组织切片作尼氏染色行病理学检查;以免疫组化方法检测Glu、CalpainⅡ、Caspase-3、Bax的表达。结果:颈内动脉注射复合血栓诱导剂可造成大鼠在Y型电迷宫中的学习和记忆成绩明显降低,与假手术对照组比较有显著差异(P<0.05)。尼氏染色可在大鼠脑片的CPU区发现胶质瘢痕化的微梗塞灶。在免疫组化结果中,Glu、CalpainⅡ、Caspase-3、Bax表达均增高。结论:单侧大脑注射复合血栓诱导剂可造成大鼠的学习记忆能力降低,可部分模拟MID的行为和病理学改变。人参皂苷Rg2能明显改善MID模型大鼠的学习记忆成绩,其作用机制可能与它的钙通道阻滞作用使凋亡蛋白CalpainⅡ、Caspase-3、Bax表达降低有关...     

川陈皮素改善衰老认知功能损伤的作用与机制

随着世界人口的老龄化,与年龄相关认知功能障碍的威胁越来越大.研究年龄相关认知功能损伤的发病机制及寻找有效的防治策略具有重要意义.我们之前的研究表明,衰老小鼠海马中S-亚硝基谷胱甘肽还原酶(S-nitrosoglutathione reductase,GSNOR)显著升高,神经元特异性高表达GSNOR转基因小鼠在行为学检测中表现出认知功能障碍.然而,其分子机制仍不清楚.在本研究中发现,CREB信号通路在GSNOR高表达转基因小鼠及原代培养小鼠海马神经元中均被GSNOR下调.在Y迷宫中检测表明,连续7 d腹腔注射CREB激活剂川陈皮素,能改善GSNOR过表达小鼠的认知损伤.进一步通过恐惧箱实验及Y迷宫测试研究川陈皮素对自然衰老小鼠认知功能的作用,发现川陈皮素能显著提高自然衰老小鼠在Y迷宫测试中的正确选择率以及在恐惧箱中的冻结时间,表明川陈皮素能显著改善衰老相关的认知功能.同样,川陈皮素上调了CREB磷酸化以及PSD95和Glu R1的水平,表明CREB信号上调在改善自然衰老认知功能损伤中发挥了重要作用.本研究为衰老认知功能损伤机制及改善方法提供了新的依据,GSNOR转基因小鼠也可能成为一种新的认知功能损伤模型.     

长期注射吗啡对戒断后小鼠Y－迷宫空间识别记忆的影响

使用急性成瘾性药物会影响大脑功能,随着药物使用时间的延长,这种影响更加广泛、持久,并且在药物戒断后的很长时间内依然存在。实验表明,急性及短期吗啡给予小鼠和戒断均损伤了其Y迷宫空间识别记忆能力,但这种损伤短暂且可逆。本实验小鼠被连续注射吗啡（40 mg/kg&#8226;day,i p）或生理盐水21天,利用Y迷宫来检测长期吗啡给予后在戒断第2、9和19天,吗啡对小鼠空间识别记忆的影响。结果表明, 连续吗啡给予21天后,在戒断第2、9和19天,小鼠Y迷宫空识别记忆能力均受到损伤,提示长期给予小鼠吗啡会导致其空间识别记忆能力的长期损伤。     

Discrimination of coloured stimuli by honeybees: alternative use of achromatic and chromatic signals

Using a Y-maze experimental set-up, honeybees Apis mellifera were trained to a coloured disc presented against an achromatic background. In subsequent tests they were given a choice between the trained disc and an alternative disc that differed either in its chromatic properties, or in the amount of achromatic green contrast that it produced against the background. Tests were conducted in two experimental situations: one in which discs subtended a visual angle of 30° (as viewed by the bee at the decision point in the Y-maze), and another in which the angle was 6.5° or 5° (depending on the experiment). At the visual angle of 30°, the bees' choice behaviour was governed by the differences in chromatic properties, and not by the differences in the amount of green contrast. With the 6.5°- and 5°-discs, on the other hand, it was governed by the differences in the amount of green contrast, and not by the differences in chromatic properties. Consequently, in the present discrimination task, bees use either chromatic or achromatic cues, depending on the visual angle subtended by the stimuli at the eye. Results of a further experiment, in which the trained disc was tested against discs that produced various amounts of green contrast, confirm the above conclusion and show, in addition, that bees learn the green-contrast difference between a trained and a non-rewarded alternative. Accepted: 25 October 1996     

Hippocampus-dependent retrieval and hippocampus-independent extinction of place avoidance navigation,and stress-induced out-of-context activation of a memory revealed by reversible lesion experiments in rats

The use of reversible lesion techniques in memory research was pioneered in the laboratory of Jan Bures and Olga Buresova. We use the occasion of Jan's 75th birthday to briefly review the experimental utility of this approach. Two experiments from our current research are reported in which reversible lesioning methods are used to ask otherwise experimentally untenable questions about memory retrieval. The first experiment used intra-hippocampal injections of tetrodotoxin to temporarily inactivate the hippocampus during retrieval of a well-learned place avoidance navigation memory. This revealed that the hippocampus is necessary for place avoidance retrieval but that the extinction of place avoidance can occur independently of retrieving the memory and intact hippocampal function. The second experiment used KCl-induced cortical spreading depression in an interhippocampal transfer paradigm to demonstrate that a Y-maze memory that is learned by only one cortical hemisphere can be made to transfer to the other hemisphere by forcing the rat to swim, a unique stressful experience that occurred in a different apparatus, different behavioral context, and involved different behaviors than the Y-maze training. This demonstrates, we believe for the first time behaviorally, that memories can be activated outside of the behavioral context of their acquisition and expression in rats.     

Computational method for prediction of protein functional sites using specificity determinants

The current available data on protein sequences largely exceeds the experimental capabilities to annotate their function. So annotation in silico, i.e. using computational methods becomes increasingly important. This annotation is inevitably a prediction, but it can be an important starting point for further experimental studies. Here we present a method for prediction of protein functional sites, SDPsite, based on the identification of protein specificity determinants. Taking as an input a protein sequence alignment and a phylogenetic tree, the algorithm predicts conserved positions and specificity determinants, maps them onto the protein's 3D structure, and searches for clusters of the predicted positions. Comparison of the obtained predictions with experimental data and data on performance of several other methods for prediction of functional sites reveals that SDPsite agrees well with the experiment and outperforms most of the previously available methods. SDPsite is publicly available under http://bioinf.fbb.msu.ru/SDPsite.     

药学专业《微生物学》实验课程改革

本文对微生物学实验课, 从设计思想、实验模块设计、考核方法、实验教材建设等方面进行了有益的探讨, 尤其是提出在实验课中设置基本技能训练、验证性实验、综合运用性实验、研究性实验等模块; 目的是提高实验课教学效果, 培养具有运用所掌握的理论知识和技能, 创造性地开展科学研究等方面工作能力的良好潜质的人才。     

药学专业《微生物学》实验课程改革

本文对微生物学实验课,从设计思想、实验模块设计、考核方法、实验教材建设等方面进行了有益的探讨,尤其是提出在实验课中设置基本技能训练、验证性实验、综合运用性实验、研究性实验等模块;目的是提高实验课教学效果,培养具有运用所掌握的理论知识和技能,创造性地开展科学研究等方面工作能力的良好潜质的人才.     

An analysis of D-amphetamine produced facilitation of avoidance acquisition in rats and performance changes subsequent to drug termination

In Experiment I rats were trained on a discriminated Y-maze active avoidance task following administration of saline or one of three dosages (.75, 1.50 or 3.0 mg/kg) of d-amphetamine. The six measures recorded simultaneously during each session indicated that the avoidance facilitation produced by d-amphetamine was due to attenuation of shock-induced behavioral suppression resulting in a behavioral baseline more compatible with the animal's associating running with shock avoidance. Results from Experiment II showed that the avoidance decrement following drug termination is dependent on training dosage and whether the drug is abruptly or gradually withdrawn. This experiment further suggested that the disruption is due to dissociation between the drug and non-drug states and could be attenuated by gradually withdrawing the drug over training sessions.     

Responsiveness to brightness change in hooded rats: effects of sex and procedure

In an investigation of recognition memory involving a preference test, hooded rats of both sexes were individually confined to the stem and choice area of a T- or Y-maze by means of clear Perspex barriers across each arm entrance that enabled the subjects to see into but not enter the arms. Following removal of the barriers and changing of one arm to opposite brightness, the first arm entered and the number of entries of and time spent in each arm were recorded. In the first experiment, rats entered first the arm that had been changed. During the first minute of observation, they also entered this novel arm more often and spent more time in it than the unchanged arm, irrespective of the type of change. In a second experiment, when the change was from one arm black and the other white to two black arms, more responsiveness occurred after 6-min prior exposure (without access) than after 3 min. In both experiments, the nature of the apparatus (T- or Y-maze) affected several outcomes, but the most significant influence was of the sex of the subjects. Females appeared less responsive to change than males as determined by entries of and time spent in the changed arm. Rather than inferiority of females in recognition or spatial memory, the sex effects were most likely due to their more rapid habituation to novelty possibly assisted by superior visual exploration capacities.     

Nicotine-induced memory impairment by increasing brain oxidative stress

Male Wistar rats were subjected to chronic nicotine treatment (0.3 mg/kg; 7 continuous days) and their memory performance was studied by means of Y-maze and multi-trial passive avoidance tasks. Nicotine significantly decreased spontaneous alternation in Y-maze task and step-through-latency in the multi-trial passive avoidance task, suggesting effects on both short-term memory and long-term memory, respectively. In addition, nicotine induced neuronal apoptosis, DNA fragmentation, reduced antioxidant enzymes activity, and increased production of lipid peroxidation and reactive oxygen species, suggesting pro-oxidant activity. Our results provide further support that nicotine-induced memory impairment is due to an increase in brain oxidative stress in rats.     

Individual odours and mate recognition in the prairie vole,Microtus ochrogaster

A habituation-discrimination technique was used to demonstrate that male and female prairie voles can discriminate individual differences in the odours of soiled shavings and urine from male and female conspecifics. A second experiment, employing a Y-maze, showed that females significantly preferred the odours of their mate over those of either another mated male or an unmated male. Males preferred their mate's odours to those of other mated females but showed no significant preference between the odours of their mate and those of a virgin female. A third experiment demonstrated that, over a 10-h period, females built nests and/or stayed preferentially on the side of a Y-maze containing their mate's odours. Likewise, males preferentially built nests in their mate's side compared to the side containing odours from a virgin female. However, although the same trend was present when mate odours were paired with odours from another mated female, the preference was not statistically significant. Taken as a whole, these results indicate that mate recognition may be an important of individually distinctive odours in this species.     

Features of rat behavior associated with alternative choice in Y-maze and their interpretation in terms of complex probability amplitudes

The two-way alternative avoidance of a weak electric shock by male Wistar rats in Y-maze was studied. The following behavioral characteristics of a rat were determined in each test series: total time of an arm choice (going away into one of two safe maze arms), number and sequence of alternate turnings to the outlets in the process of choice, time of immobility in the Y-maze center, and "freezing" reaction. Rat behavior of choice of safe arms in Y-maze be interpreted on the basis of the rules of summation of complex probability amplitudes, which characterize a predictive estimation of achievement by a rat of its relative safety. With the need to avoid an electric shock, rat's estimations of suitabilities of two different avoidance ways can interfere. This makes it difficult for an animal to take a choice decision (if both pathways are equally acceptable for a rat). After entering a safe arm, sometimes a rat can leave it for another arm, such passages occur quasiperiodically.