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1.
Chinese Medical Sciences Journal ; (4): 29-37, 2023.
Article in English | WPRIM | ID: wpr-981590

ABSTRACT

Objective We aimed to investigate whether antagonism of the cannabinoid CB1 receptor (CB1R) could affect novel object recognition (NOR) memory in chronically rapid eye movement sleep-deprived (RSD) rats.Methods The animals were examined for recognition memory following a 7-day chronic partial RSD paradigm using the multiple platform technique. The CB1R antagonist rimonabant (1 or 3 mg/kg, i.p.) was administered either at one hour prior to the sample phase for acquisition, or immediately after the sample phase for consolidation, or at one hour before the test phase for retrieval of NOR memory. For the reconsolidation task, rimonabant was administered immediately after the second sample phase.Results The RSD episode impaired acquisition, consolidation, and retrieval, but it did not affect the reconsolidation of NOR memory. Rimonabant administration did not affect acquisition, consolidation, and reconsolidation; however, it attenuated impairment of the retrieval of NOR memory induced by chronic RSD.Conclusions These findings, along with our previous report, would seem to suggest that RSD may affect different phases of recognition memory based on its duration. Importantly, it seems that the CB1R may, at least in part, be involved in the adverse effects of chronic RSD on the retrieval, but not in the acquisition, consolidation, and reconsolidation, of NOR memory.


Subject(s)
Rats , Animals , Rimonabant/pharmacology , Memory , Sleep, REM , Receptors, Cannabinoid , Cannabinoids/pharmacology
2.
Journal of Biomedical Engineering ; (6): 692-699, 2023.
Article in Chinese | WPRIM | ID: wpr-1008889

ABSTRACT

With inherent sparse spike-based coding and asynchronous event-driven computation, spiking neural network (SNN) is naturally suitable for processing event stream data of event cameras. In order to improve the feature extraction and classification performance of bio-inspired hierarchical SNNs, in this paper an event camera object recognition system based on biological synaptic plasticity is proposed. In our system input event streams were firstly segmented adaptively using spiking neuron potential to improve computational efficiency of the system. Multi-layer feature learning and classification are implemented by our bio-inspired hierarchical SNN with synaptic plasticity. After Gabor filter-based event-driven convolution layer which extracted primary visual features of event streams, we used a feature learning layer with unsupervised spiking timing dependent plasticity (STDP) rule to help the network extract frequent salient features, and a feature learning layer with reward-modulated STDP rule to help the network learn diagnostic features. The classification accuracies of the network proposed in this paper on the four benchmark event stream datasets were better than the existing bio-inspired hierarchical SNNs. Moreover, our method showed good classification ability for short event stream input data, and was robust to input event stream noise. The results show that our method can improve the feature extraction and classification performance of this kind of SNNs for event camera object recognition.


Subject(s)
Visual Perception , Learning , Action Potentials , Neural Networks, Computer , Neuronal Plasticity
3.
Acta Pharmaceutica Sinica B ; (6): 2152-2175, 2023.
Article in English | WPRIM | ID: wpr-982849

ABSTRACT

We describe the development of quinolylnitrones (QNs) as multifunctional ligands inhibiting cholinesterases (ChEs: acetylcholinesterase and butyrylcholinesterase-hBChE) and monoamine oxidases (hMAO-A/B) for the therapy of neurodegenerative diseases. We identified QN 19, a simple, low molecular weight nitrone, that is readily synthesized from commercially available 8-hydroxyquinoline-2-carbaldehyde. Quinolylnitrone 19 has no typical pharmacophoric element to suggest ChE or MAO inhibition, yet unexpectedly showed potent inhibition of hBChE (IC50 = 1.06 ± 0.31 nmol/L) and hMAO-B (IC50 = 4.46 ± 0.18 μmol/L). The crystal structures of 19 with hBChE and hMAO-B provided the structural basis for potent binding, which was further studied by enzyme kinetics. Compound 19 acted as a free radical scavenger and biometal chelator, crossed the blood-brain barrier, was not cytotoxic, and showed neuroprotective properties in a 6-hydroxydopamine cell model of Parkinson's disease. In addition, in vivo studies showed the anti-amnesic effect of 19 in the scopolamine-induced mouse model of AD without adverse effects on motoric function and coordination. Importantly, chronic treatment of double transgenic APPswe-PS1δE9 mice with 19 reduced amyloid plaque load in the hippocampus and cortex of female mice, underscoring the disease-modifying effect of QN 19.

4.
European J Med Plants ; 2022 Mar; 33(3): 18-24
Article | IMSEAR | ID: sea-219472

ABSTRACT

Green tea has been reported to result in improvements in a range of health parameters. However, most research has only documented the effects of green tea brewed from leaves or leaf extracts. In addition to the leaves, the roots of tea plants also possess unique properties because of their requirements for growth, which may enable them to have useful physiological effects. We used a hydroponic system to grow the plants and explored the physiological effects of the roots, which biosynthesize one of the rarest functional amino acids, theanine (?-ethylamide-L-glutamic acid). The level of theanine was much higher in the roots than in the leaves, and the roots also differed in other aspects of their chemical composition. We evaluated the effects of tea-root extract on the cognitive function and emotions of aged rats. Our results show that, in the object recognition test, aged rats drinking tea-root extract tended to show improved cognitive function and were more relaxed than the control group, which drank tap water. Furthermore, using a mouse model of human aging, we found that the average life span of mice that consumed the root extract was significantly increased. We suggest that tea roots contain unique components that may improve impaired physiological functions, and we therefore propose tea-root extract as a novel nutraceutical.

5.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 63-69, 2021.
Article in Chinese | WPRIM | ID: wpr-906456

ABSTRACT

Objective:To determine the contents of inorganic arsenic(iAs),monomethylarsonic acid(MMA) and dimethylarsinic acid(DMA) in brain tissues and blood by using hydride generation-cold trap-atomic absorptionspectrometry(HG-CT-AAS), and to explore the toxic effects of Realgar on central nervous system of rats. Method:The 96 Wistar rats were randomly divided into 4 groups:normal control group,0.3,0.9 and 2.7 g·kg<sup>-1</sup> Realgar groups. They then received intragastric administration for 14,28 and 42 days respectively, so a total of 12 groups were formed, with 8 animals in each group. The normal group was given the same dose of sodium carboxymethyl cellulose (CMC-Na) by gavage. The contents of iAs,MMA and DMA in blood and brain tissues were determined by HG-CT-AAS. The novel object recognition test was conducted to observe the learning and memory ability of rats. The changes of hippocampal neuron ultrastructure were observed by transmission electron microscopy. Result:There was no difference in the growth,weight and hippocampal coefficient of the experimental animals. The method of HG-CT-AAS showed a good linearity,precision,accuracy and recovery in content determination of arsenic (at various forms) in rat brain and blood. MMA and DMA were detected in the brain of realgar groups at time-dose-effect relationship. iAs,MMA and DMA were detected in the blood of Realgar groups. The nuclear membrane, mitochondria and endoplasmic reticulum in hippocampus neurons of rats were gradually damaged with the increase of Rhubarb exposure dose and time. After 14 days of exposure to Realgar,compared with the normal control group,there was no significant difference in the novel object recognition index among Realgar groups. After 28 days of exposure,only 2.7 g·kg<sup>-1</sup> Realgar group showed statistically significant difference with the control group (<italic>P</italic><0.05). After 42 days of exposure, the novel object recognition index of 0.9 and 2.7 g·kg<sup>-1</sup> Realgar groups was significantly lower than that in normal control group(<italic>P</italic><0.05). Conclusion:The metabolites of Realgar in rats are iAs,MMA and DMA. MMA and DMA can be accumulated in the brain tissue through the blood-brain barrier,causing the decline of the ability of learning and memory and leading to damage of hippocampal neurons.

6.
Psicol. pesq ; 14(spe): 1-15, 2020.
Article in English | LILACS-Express | LILACS, INDEXPSI | ID: biblio-1155170

ABSTRACT

In contrast to many machine vision systems, we human observers can readily recognize solid objects and visually discriminate their 3-D shapes even under changes in viewpoint and variations in object orientation and lighting. While the importance of binocular disparity has been known since the 1830's, the importance and perceptual informativeness of visual contours for object recognition and discrimination is not adequately appreciated. This article will review those scientific contributions that demonstrate that visual contours and their deformations over time (in response to object or observer motion) carry as much or more information about object shape than other forms of visual information.


Em contraste com muitos sistemas artificiais de visão, nós, observadores humanos, podemos reconhecer prontamente objetos sólidos e discriminar visualmente suas formas 3-D, mesmo sob mudanças no ponto de vista e variações na orientação e iluminação do objeto. Embora a importância da disparidade binocular seja conhecida desde a década de 1830, a relevância e a riqueza perceptiva das informações fornecidas pelos contornos visuais para o reconhecimento e discriminação de objetos não são devidamente apreciadas. Este artigo revisará as contribuições científicas que demonstram que os contornos visuais e suas deformações ao longo do tempo (em resposta ao movimento do objeto ou do observador) proporcionam tanto ou mais informações sobre a forma do objeto do que outras formas de informação visual.


A diferencia de los sistemas de visión artificial, los observadores humanos pueden reconocer fácilmente objetos sólidos y discriminar visualmente su forma 3D, incluso cuando se producen cambios en su punto de vista, en la orientación o en la iluminación. Aunque la importancia de la disparidade binocular es conocida desde 1830, la relevancia y la riqueza de la información provista por los contornos visuales para el reconocimiento y discriminación de los objetos no ha sido apreciada adecuadamente. En este artículo se revisan las contribuciones científicas que demuestran que los contornos visuales y sus deformaciones a lo largo del tiempo (en respuesta a los movimentos tanto del observador como del objeto) proporcionan tanto o más información sobre la forma del objeto que otros tipos de información visual.

7.
Journal of Biomedical Engineering ; (6): 380-388, 2020.
Article in Chinese | WPRIM | ID: wpr-828156

ABSTRACT

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive brain stimulation technique that has been paid attention to with increasing interests as a therapeutic neural rehabilitative tool. Studies confirmed that high-frequency rTMS could improve the cognitive performance in behavioral test as well as the excitability of the neuron in animals. This study aimes to investigate the effects of rTMS on the cognition and neuronal excitability of Kunming mice during the natural aging. Twelve young mice, 12 adult mice, and 12 aged mice were used, and each age group were randomly divided into rTMS group and control group. rTMS-treated groups were subjected to high-frequency rTMS treatment for 15 days, and control groups were treated with sham stimulation for 15 days. Then, novel object recognition and step-down tests were performed to examine cognition of learning and memory. Whole-cell patch clamp technique was used to record and analyze resting membrane potential, action potential (AP), and related electrical properties of AP of hippocampal dentate gyrus (DG) granule neurons. Data analysis showed that cognition of mice and neuronal excitability of DG granule neurons were degenerated significantly as the age increased. Cognitive damage and degeneration of some electrical properties were alleviated under the condition of high-frequency rTMS. It may be one of the mechanisms of rTMS to alleviate cognitive damage and improve cognitive ability by changing the electrophysiological properties of DG granule neurons and increasing neuronal excitability.

8.
Braz. j. med. biol. res ; 52(5): e8026, 2019. tab, graf
Article in English | LILACS | ID: biblio-1001526

ABSTRACT

Carassius auratus is a teleost fish that has been largely used in behavioral studies. However, little is known about potential environmental influences on its performance of learning and memory tasks. Here, we investigated this question in C. auratus, and searched for potential correlation between exercise and visuospatial enrichment with the total number of telencephalic glia and neurons. To that end, males and females were housed for 183 days in either an enriched (EE) or impoverished environment (IE) aquarium. EE contained toys, natural plants, and a 12-hour/day water stream for voluntary exercise, whereas the IE had none of the above. A third plus-maze aquarium was used for spatial and object recognition tests. Different visual clues in 2 of its 4 arms were used to guide fish to reach the criteria to complete the task. The test consisted of 30 sessions and was concluded when each animal performed three consecutive correct choices or seven alternated, each ten trials. Learning rates revealed significant differences between EE and IE fish. The optical fractionator was used to estimate the total number of telencephalic cells that were stained with cresyl violet. On average, the total number of cells in the subjects from EE was higher than those from subjects maintained in IE (P=0.0202). We suggest that environmental enrichment significantly influenced goldfish spatial learning and memory abilities, and this may be associated with an increase in the total number of telencephalic cells.


Subject(s)
Animals , Male , Female , Telencephalon/metabolism , Cell Proliferation/physiology , Fishes/physiology , Spatial Learning/physiology , Spatial Memory/physiology , Physical Conditioning, Animal , Behavior, Animal/physiology , Cell Count
9.
Laboratory Animal Research ; : 154-164, 2019.
Article in English | WPRIM | ID: wpr-786408

ABSTRACT

In the present study, we investigated the effects of heat shock protein 70 (HSP70) on novel object recognition, cell proliferation, and neuroblast differentiation in the hippocampus. To facilitate penetration into the blood–brain barrier and neuronal plasma membrane, we created a Tat-HSP70 fusion protein. Eight-week-old mice received intraperitoneal injections of vehicle (10% glycerol), control-HSP70, or Tat-HSP70 protein once a day for 21 days. To elucidate the delivery efficiency of HSP70 into the hippocampus, western blot analysis for polyhistidine was conducted. Polyhistidine protein levels were significantly increased in control-HSP70- and Tat-HSP70-treated groups compared to the control or vehicle-treated group. However, polyhistidine protein levels were significantly higher in the Tat-HSP70-treated group compared to that in the control-HSP70-treated group. In addition, immunohistochemical study for HSP70 showed direct evidences for induction of HSP70 immunoreactivity in the control-HSP70- and Tat-HSP70-treated groups. Administration of Tat-HSP70 increased the novel object recognition memory compared to untreated mice or mice treated with the vehicle. In addition, the administration of Tat-HSP70 significantly increased the populations of proliferating cells and differentiated neuroblasts in the dentate gyrus compared to those in the control or vehicle-treated group based on the Ki67 and doublecortin (DCX) immunostaining. Furthermore, the phosphorylation of cAMP response element-binding protein (pCREB) was significantly enhanced in the dentate gyrus of the Tat-HSP70-treated group compared to that in the control or vehicle-treated group. Western blot study also demonstrated the increases of DCX and pCREB protein levels in the Tat-HSP70-treated group compared to that in the control or vehicle-treated group. In contrast, administration of control-HSP70 moderately increased the novel object recognition memory, cell proliferation, and neuroblast differentiation in the dentate gyrus compared to that in the control or vehicle-treated group. These results suggest that Tat-HSP70 promoted hippocampal functions by increasing the pCREB in the hippocampus.


Subject(s)
Animals , Mice , Blotting, Western , Cell Membrane , Cell Proliferation , Cyclic AMP Response Element-Binding Protein , Dentate Gyrus , Heat-Shock Proteins , Hippocampus , Hot Temperature , HSP70 Heat-Shock Proteins , Injections, Intraperitoneal , Memory , Neurons , Phosphorylation
10.
Laboratory Animal Research ; : 239-247, 2018.
Article in English | WPRIM | ID: wpr-718843

ABSTRACT

Bacopa monnieri is a medicinal plant with a long history of use in Ayurveda, especially in the treatment of poor memory and cognitive deficits. In the present study, we hypothesized that Bacopa monnieri extract (BME) can improve memory via increased cell proliferation and neuroblast differentiation in the dentate gyrus. BME was administered to 7-week-old mice once a day for 4 weeks and a novel object recognition memory test was performed. Thereafter, the mice were euthanized followed by immunohistochemistry analysis for Ki67, doublecortin (DCX), and phosphorylated cAMP response element-binding protein (CREB), and western blot analysis of brain-derived neurotrophic factor (BDNF). BME-treated mice showed moderate increases in the exploration of new objects when compared with that of familiar objects, leading to a significant higher discrimination index compared with vehicle-treated mice. Ki67 and DCX immunohistochemistry showed a facilitation of cell proliferation and neuroblast differentiation following the administration of BME in the dentate gyrus. In addition, administration of BME significantly elevated the BDNF protein expression in the hippocampal dentate gyrus, and increased CREB phosphorylation in the dentate gyrus. These data suggest that BME improves novel object recognition by increasing the cell proliferation and neuroblast differentiation in the dentate gyrus, and this may be closely related to elevated levels of BDNF and CREB phosphorylation in the dentate gyrus.


Subject(s)
Animals , Mice , Bacopa , Blotting, Western , Brain-Derived Neurotrophic Factor , Cell Proliferation , Cognition Disorders , Cyclic AMP Response Element-Binding Protein , Dentate Gyrus , Discrimination, Psychological , Immunohistochemistry , Memory , Neurogenesis , Phosphorylation , Plants, Medicinal
11.
Chinese Journal of Comparative Medicine ; (6): 21-27, 2018.
Article in Chinese | WPRIM | ID: wpr-703290

ABSTRACT

Objective To develop a multi-mode,detailed and sensitive object recognition method for learning and memory research,including novel object recognition task,object location recognition task,temporal order memory task and object context recognition task in animals based on their spontaneous behavior. Methods Two strains of mice(KM and ICR)and four patterns were used to establish the object recognition method and several relative factors,such as time of test phase,delay between test phase and familiar phase were investigated. Results It was stable and reasonable to set the time of familiar phase as 5 min,the interval between test phase and familiar phase as 10 min,and the time of test phase as 3-5 min,under the precondition of habituation for three days and selecting the appropriate object pairs. Conclusions Object recognition test including four patterns has been systematically established as a stable, reliable and normative way for the research of animal learning and memory and drug development.

12.
Univ. psychol ; 16(1): 3-11, Jan.-Mar. 2017. graf
Article in English | LILACS, COLNAL | ID: biblio-904611

ABSTRACT

ABSTRACT The present study aimed to determine the optimum response time (RT) needed to identify images of everyday objects when filtered using different spatial frequency bands. Subjects were randomly presented with different images of familiar objects that were both serialized and progressive in their spatial frequencies. The time needed to recognize them was then measured. The results showed that the optimum RT for identifying an image filtered in different spatial frequency bands was approximately 2000 ms of exposure. Specifically, stimuli presented using spatial frequency bands with Gaussian filters of variance V26-V32, which were familiar and of medium size to the viewer, were recognized in a mean time of 2126 ms.


RESUMEN El presente estudio tiene como objetivo determinar el tiempo de respuesta óptimo (RT) necesario para identificar imágenes de objetos cotidianos cuando se filtran utilizando diferentes bandas de frecuencias espaciales. A los sujetos se les presentaba aleatoriamente diferentes imágenes de objetos familiares cuyas bandas de frecuencia eran progresivamente serializadas. Se midió el tiempo necesario para reconocerlos. Los resultados mostraron que la RT óptima para identificar una imagen filtrada en diferentes bandas de frecuencias espaciales fue de aproximadamente 2000 ms de exposición. En concreto, los estímulos presentados utilizando bandas de frecuencias espaciales con filtros gaussianos de varianza V26-V32, que eran familiares y de tamaño medio para el espectador, se reconocieron en un tiempo medio de 2126 ms.


Subject(s)
Reaction Time , Visual Perception
13.
Medical Journal of Chinese People's Liberation Army ; (12): 617-622, 2017.
Article in Chinese | WPRIM | ID: wpr-613691

ABSTRACT

Objective To investigate effects of physical exercise (PE) on object recognition memory in adult rats of postnatal isoflurane (Iso) exposures.Methods One hundred and ten postnatal 7-day SD rats (P7) were randomly divided into four groups: normal control group (Naive), Naive+PE group (received physical exercise in P21: a treadmill exercise 30min each day, 5 times/week, for 6 weeks), Iso group (three times of 2-hour Iso exposure in P7, P9, and P11), and Iso+PE group (received PE in P21 after postnatal Iso exposures). In P67, behavioral testing was conducted including open field and object recognition task (ORT), recording the time (Discrimination Ratios, DR) that rats spent on exploring each object, evaluating effects of PE on object recognition memory.Results There was no significant difference in influence of PE on open field testing in all of the groups (P>0.05). Compared with Naive, there was no group difference in DR (P>0.05) for all groups, but the DR of Iso male rats was significantly higher than that of Naive female rats in P67, with significant difference (P=0.034). Compared with non-PE groups, whether or not postnatal Iso exposures, the DR of PE male groups was significantly higher (compared with Naive and Iso group:P67,P=0.050,P=0.017; P95,P=0.037,P=0.019); in female rats, the DR for ISO+PE group was lower than that of Iso group in P67 (P=0.036), but the DR of Naive+PE group was higher than that of Naive group in P95 (P=0.004). Compared with male rats, the DR of non-PE female rats was significantly higher in P67 (vis. Naive and Iso group:P=0.022,P=0.011); but in P95, the DR of non-Iso female groups was significantly higher than that of male groups (vis. Naive and Naive+PE:P=0.008,P=0.017).Conclusions There is no obvious impact of postnatal Iso exposures on object recognition memory of adult rats. These Results also indicate that postnatal PE could improve object recognition memory of non-spatial learning in adult rats. In addition, exercise benefits have gender differences.

14.
Chinese Journal of Pharmacology and Toxicology ; (6): 1057-1062, 2017.
Article in Chinese | WPRIM | ID: wpr-705221

ABSTRACT

The capability of visual object recognition in primates is excellent, which is crucial to their survival. The investigation and analysis of the neural mechanisms underlying the visual object recognition in primates might bring dramatic breakthroughs to the brain-like machine vision.There are hierarchical structures, parallel pathways, feedback mechanisms, attention and visual search in the visual system of primates, which makes the visual object recognition in primates accurate, effective, flexible and energy-saving. The visual system of primates might achieve object detection through fast image segmentation by global precedence.The categorization manner of object encoding and storage makes possible the quick classification of detected objects.The potential target is selected by comparing the object and internal template of the target. The orienting between detected objects is guided by feature-based attention and spatial attention. The final step is the identification of the potential target. Previous studies of the visual object recognition in primates have made a series of progress.However, the detailed mechanisms of neuronal coding remain unclear and need further investigations.

15.
Rev. mex. ing. bioméd ; 37(2): 101-114, May.-Aug. 2016. tab, graf
Article in Spanish | LILACS | ID: biblio-961316

ABSTRACT

Resumen: En la práctica clínica relacionada con la rehabilitación cognitiva, perceptual y del lenguaje, es habitual emplear como estímulos representaciones de objetos en dos dimensiones como dibujos o fotografías para que sean identificados por los pacientes. Ello supone una limitación, puesto que la presentación de objetos en tres dimensiones, dada su mayor riqueza visual, facilita su identificación y podría apoyar procesos de rehabilitación. Objetivo: Diseñar una configuración experimental para conocer el grado en que las modalidades de presentación de estímulos afectan el reconocimiento visual de objetos. Materiales y Métodos: Se diseñó un sistema de bajo costo para mostrar estímulos en tres modalidades: imágenes, videos y objetos reales. Fueron seleccionados 80 objetos, controlando las variables de manipulabilidad, edad de adquisición, familiaridad, complejidad visual y frecuencia léxica. Se realizó una prueba piloto utilizando el sistema con cinco personas sanas y se midieron los tiempos de reacción en la nominación de los objetos. Resultados: Las diferencias en los tiempos de reacción entre las modalidades observadas apoyan la influencia de la modalidad de presentación en el reconocimiento de objetos. Conclusiones: Las propiedades de volumen de los objetos permitirían la exploración de características que las fotografías no tendrían; razón por la cual, los tiempos de reacción para los objetos reales y los videos fueron menores. Son valiosos los aportes que ofrecen una alternativa de bajo costo para la visualización y el reconocimiento de objetos.


Abstract: A wide variety of stimuli or objects such as drawings or photographs are used in cognitive perceptual and language rehabilitation. However, the presentation of objects in three dimensions, due to the visual richness, facilitates the identification and could support the rehabilitation process. Objective: Design an experimental setup to determine the extent to which the modality of presentation of objects affects the visual recognition of objects. Materials and methods: A low-cost experimental system was designed in order to show the stimulus in three ways: images, videos and real objects. Eighty objects were selected and variables as manipulability, age of acquisition, familiarity, visual complexity, agreement on the label and lexical frequency were controlled. A pilot study was conducted using the system in five healthy participants and the reaction time to identify objects was measured. Results: The findings reveal that the differences in reaction times between the modalities of presentation support the influence of the mode of presentation in object recognition. Conclusions: The volume object properties could allow the exploration of characteristics that the photographs would not have. This may be why the reaction time to identify real objects or videos was lower. Low-cost alternatives for the visualization and object recognition are valuable in cognitive perceptual and language rehabilitation.

16.
Laboratory Animal Research ; : 224-230, 2016.
Article in English | WPRIM | ID: wpr-221834

ABSTRACT

We investigated the effects of the sirtuin-2 (SIRT2) inhibitor AK-7 on novel object memory, cell proliferation, and neuroblast differentiation in the dentate gyrus. In addition, we also observed the relationships with sodium butyrate, a histone deacetylase inhibitor, on the hippocampal functions. To investigate the effects of AK-7 on hippocampal functions, 10-week-old C57BL/6 mice were daily injected intraperitoneally with 20 mg/kg AK-7 alone or in combination with subcutaneous administration of 300 mg/kg sodium butyrate, a histone deacetylase inhibitor, for 21 days. A novel object recognition test was conducted on days 20 (training) and 21 (testing) of treatment. Thereafter, the animals were sacrificed for immunohistochemistry for Ki67 (cell proliferation) and doublecortin (DCX, neuroblast differentiation). AK-7 administration significantly reduced the time spent exploring new objects, while treatment in combination with sodium butyrate significantly alleviated this reduction. Additionally, AK-7 administration significantly reduced the number of Ki67-positive cells and DCX-immunoreactive neuroblasts in the dentate gyrus, while the treatment in combination with sodium butyrate ameliorated these changes. This result suggests that the reduction of SIRT2 may be closely related to age-related phenotypes including novel object memory, as well as cell proliferation and neuroblast differentiation in the dentate gyrus. In addition, sodium butyrate reverses SIRT2-related age phenotypes.


Subject(s)
Animals , Mice , Butyric Acid , Cell Proliferation , Dentate Gyrus , Histone Deacetylase Inhibitors , Immunohistochemistry , Memory , Neurogenesis , Phenotype , Sirtuin 2 , Sodium
17.
Arq. bras. med. vet. zootec ; 67(3): 873-881, May-Jun/2015. tab, graf
Article in Portuguese | LILACS | ID: lil-753911

ABSTRACT

Objetivou-se com esta pesquisa avaliar, por meio de testes de preferência, a capacidade de percepção de pintos de corte no reconhecimento de objetos e alimentos de diferentes cores. A pesquisa foi realizada no Brasil e consistiu no condicionamento de 60 pintos de um dia sexados, sendo 30 pintos machos e 30 pintos fêmeas, durante três dias, com esferas azuis e alimento vermelho, cores escolhidas por terem cromaticidades opostas. Após a fase de condicionamento, foi realizado um teste de preferência, no qual os animais eram colocados individualmente no centro de uma arena de teste com quatro opções, sendo elas: alimento vermelho; alimento azul; esferas vermelhas; esferas azuis. Cada ave foi avaliada durante 10 minutos...


The aim of this research was to evaluate, by preference tests, the ability of perception of broiler chicks in the recognition of objects and foods of different colors. The survey was conducted in Brazil and consisted in the conditioning of 60 sexed one-day-old chicks using 30 male chicks and 30 female chicks for three days with blue balls and red food colors chosen for having opposed chromaticities. After the conditioning phase, a preference test was performed, in which the animals were placed individually in the center of an arena test with four options: red food, blue food, red balls and blue balls. Each bird was measured for 10 minutes...


Subject(s)
Animals , Cognition , Color Perception , Conditioning, Psychological , Pattern Recognition, Physiological , Behavior, Animal
18.
Chinese Journal of Behavioral Medicine and Brain Science ; (12): 427-430, 2015.
Article in Chinese | WPRIM | ID: wpr-669926

ABSTRACT

Objective To investigate the early onset of learning and memory function of 4-month-old APP/PS1/Tau Alzheimer' s disease (3×Tg-AD) model mice and explore the pathogenesis of AD in early stage through evaluating neuron excitability and BKCa channel activity in cingulate cortex pyramidal cells.Methods Ten 4-month-old male 3×Tg-AD mice and matched ten wild type (WT) mice.Behavior was tested with the novel object recognition task to observe the ability of learning and memory.Whole-cell patch-clamp recordings were performed to assess the excitability of cingulate cortex pyramidal cells in terms of resting membrane potential and frequencies of spikes evoked by current injection.A train of five pulses of depolarizing currents were injected at 100 Hz to assess the spike width,which was used as an index for BKCa channel activity.Results Compared with the WT group (0.72±0.03),the novel object recognition index significantly decreased in 3 × Tg-AD group (0.55 ± 0.04) (P =0.004).Compared to the WT group((-66.03±0.43) mV),the resting membrane potential in cingulate cortex neurons of 3×Tg-AD group((-62.31±0.54)mV) was significantly depolarized(P=0.000).In contrast to WT group,the action potential firing frequencies evoked by depolarizing current injections were higher in neurons from 3×Tg-AD group(P=0.000),demonstrating that excitability of cingulate cortex neurons was elevated by intracellular Aβ.Spikes were broader in the 3×Tg-AD group than those in the WT group(P<0.01).Suppression of BKCa channels in cingulate cortex neurons from the 3×Tg-AD group was confirmed on the basis of the spike half-width,since BKCa channels affect the descending phase of spikes.Conclusion Compared to WT mice,4-month-old 3×Tg-AD mice are impaired in learning and memory.The suppression of BKCa channels by intracellular Aβ leads to increase of excitability in cingulate cortex pyramidal cells.

19.
Acta Laboratorium Animalis Scientia Sinica ; (6): 40-44, 2014.
Article in Chinese | WPRIM | ID: wpr-448297

ABSTRACT

Objective To investigate the effects of chronic restraint stress on learning and memory in Wistar and Sprague-Dawley (SD) rats.Methods Healthy adult male Wistar rats (n=6) and Sprague-Dawley rats (n=6) were subjected to restraint stress 10 h daily for 28 days.After that, all rats were tested for recognition memory by novel object recognition test , and spatial memory and working memory by Morris water maze test .Results After restraint for 10 h daily for 28 days, the restraint rats of the two strains demonstrated lower discrimination index (DI)than the control group, but on-ly SD rats showed significant difference ( P<0.05 ) .The restraint SD rats showed higher escape latency than the control rats, and on the 5th day the difference became significant (P<0.05), and there was no significant difference between Wistar restraint and control rats .The working memory test showed that restraint SD rats exibited longer escape latency than the control rats (P<0.05), while Wistar rats didn’t show significant difference between the two groups .Conclusions The results of this study demonstrate that the impairments of learning and memory in SD rats subjected to restraint 10 hour per day for 28 days are more serious than that in the Wistar rats .Therefore , SD rats may be a better choice as an animal model to study the effects of chronic restraint stress on learning and memory impairment .

20.
Psychol. neurosci. (Impr.) ; 6(3): 403-410, July-Dec. 2013. graf
Article in English | LILACS | ID: lil-703104

ABSTRACT

Simvastatin is one of many hydroxymethylglutaryl-coenzyme-A reductase inhibitors that are prescribed to lower cholesterol. Some emerging evidence indicates that classical music can serve as an effective adjuvant in rats treated with simvastatin. Moreover, simvastatin and classical music have been shown to influence some cognitive functions. To further understand the mechanisms of action, we exposed rats to classical music for 1 month, and then treated them orally with simvastatin. The behavioral experiments suggested that exposure to subchronic simvastatin (1 or 10 mg/kg/day) reduced anxiety levels in the elevated plus-maze and open-field test in rats exposed to Mozart music. The recognition object test results indicated that simvastatin altered non-spatial working memory only at the 1 mg/kg/day dose and improved both short- and long-term object recognition. No significant differences were found between Mozart music and silence in the object recognition test, suggesting that music did not significant affect learning and memory in adult rats. We hypothesize that the anxiolytic, but not object-recognition memory, effects of simvastatin and classical music occur through similar mechanisms, providing an important foundation for future preclinical and clinical research...


Subject(s)
Animals , Rats , Anxiety , Music , Memory, Short-Term , Memory, Long-Term , Simvastatin/adverse effects , Rats, Inbred Strains
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