Este trabalho foi financiado pelo Instituto Nacional de Ciências Médicas Gerais (Reed / Engler-Chiurazzi - U54GM104942), do Instituto Nacional de Distúrbios Neurológicos e Derrame (Ashe - R01NS33249, R01NS63249 e R01NS79374), Cobre (Engler-Chiurazzi - P20GM109098), o Associação de Alzheimer (Reed - NIRG-12-242187), um WVU Faculdade Senado Research Grant (Reed), uma subvenção WVU PSCOR (Reed), e fundos internos da faculdade de WVU do Escritório de Medicina Dean (Engler-Chiurazzi). O conteúdo é da exclusiva responsabilidade dos autores e não representam necessariamente a posição oficial do NIH ou Associação de Alzheimer.

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P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Applications+of+the+morris+water+maze+in+the+study+of+learning+and+memory.">Applications of the morris water maze in the study of learning and memory.</a> Brain Research Reviews. 36, 60-90 (2001).</li><li>Santa Cruz, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tau+suppression+in+a+neurodegenerative+mouse+model+improves+memory+function.">Tau suppression in a neurodegenerative mouse model improves memory function.</a> Science. 309, 476-481 (2005).</li><li>Hunsberger, H. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+size+of+memory+deficits+in+mice+with+adult-onset+P301L+tau+expression.">Effect size of memory deficits in mice with adult-onset P301L tau expression.</a> Behavioural Brain Research. 272, 181-195 (2014).</li><li>Yue, M., Hanna, A., Wilson, J., Roder, H., Janus, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sex+difference+in+pathology+and+memory+decline+in+rTg4510+mouse+model+of+tauopathy.">Sex difference in pathology and memory decline in rTg4510 mouse model of tauopathy.</a> Neurobiology of Aging. 32, 590-603 (2011).</li><li>Sandi, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+and+mechanisms+of+action+of+glucocorticoid+involvement+in+memory+storage.">The role and mechanisms of action of glucocorticoid involvement in memory storage.</a> Neural plasticity. 6, 41-52 (1998).</li><li>H&#246;lscher, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=C.+impairs+performance+in+spatial+water+maze+learning+tasks.">C. impairs performance in spatial water maze learning tasks.</a> Behavioural Brain Research. 100, 225-235 (1999).</li><li>Morris, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Developments+of+a+water-maze+procedure+for+studying+spatial+learning+in+the+rat.">Developments of a water-maze procedure for studying spatial learning in the rat.</a> Journal of Neuroscience Methods. 11, 47-60 (1984).</li><li>Reed, M. N., Liu, P., Kotilinek, L. A., Ashe, K. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+size+of+reference+memory+deficits+in+the+morris+water+maze+in+Tg2576+mice.">Effect size of reference memory deficits in the morris water maze in Tg2576 mice.</a> Behavioural Brain Research. 212, 115-120 (2010).</li><li>Huang, Y., Zhou, W., Zhang, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bright+lighting+conditions+during+testing+increase+thigmotaxis+and+impair+water+maze+performance+in+BALB/c+mice.">Bright lighting conditions during testing increase thigmotaxis and impair water maze performance in BALB/c mice.</a> Behavioral Brain Research. 226, 26-31 (2012).</li><li>Ivonen, H., Nurminen, L., Harri, M., Tanila, H., Puolivali, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypothermia+in+mice+tested+in+Morris+water+maze.">Hypothermia in mice tested in Morris water maze.</a> Behavioural Brain Research. 141, 207-213 (2003).</li><li>Rubinow, M. J., Arseneau, L. M., Beverly, J. L., Juraska, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+estrous+cycle+on+water+maze+acquisition+depends+on+the+temperature+of+the+water.">Effect of estrous cycle on water maze acquisition depends on the temperature of the water.</a> Behavioral Neuroscience. 118 (4), 863-868 (2004).</li></ol>

Os autores não têm nada a revelar.

A tarefa MWM é amplamente utilizado para avaliar a aprendizagem espacial ea memória. No entanto, a robustez desta tarefa pode ser influenciada por muitos factores e requer optimização tanto para estirpe fundo e ambiente de teste. Como mostrado na Figura 4, o mesmo protocolo de treino e aplicados sinais visuais usados ​​em dois quartos de teste diferentes (de tamanho e de disposição equivalente) produziram significativamente diferente desempenho da sonda. Uma vez que muitas características da ...

Modelos de ratinhos transgénicos têm sido fundamentais para avaliar a patofisiologia da doença de Alzheimer (AD), assim como o potencial de intervenções terapêuticas. Tarefas cognitivas, tais como o labirinto de água de Morris (MWM), são comumente usados ​​com estes modelos para identificar as correlações moleculares de défices de memória e para avaliar a eficácia de drogas pré-clínicos. É essencial, no entanto, que o intervalo dinâmico da tarefa cognitiva ser grande o suficiente para detectar os efeitos do tratamento subtis. Com modelos do rato do AD, déficits cognitivos são tipicamente dependente da idade, e camundongos exibir declínios progressivos no desempenho (por exemplo, 1). Uso de uma tarefa cognitiva sensível pode permitir a detecção de diferenças subtis no início da vida do animal, reduzindo assim os custos associados com os animais de envelhecimento. Por exemplo, a redução do número de ensaios de formação nos Barnes dependente do hipocampo labirinto 15-5 aumentado a dificuldade da tarefa, resultando na detection de déficits no modelo 3xTg em uma idade mais cedo do que anteriormente relatados 2. A detecção precoce de défices não só oferece um tempo considerável e economia de custos, mas também aumenta a probabilidade de que as alterações moleculares subjacentes défices cognitivos podem ser identificados. Um fator que influencia a sensibilidade de tarefas cognitivas é o fundo genético estirpe do modelo do rato. Por exemplo, ratinhos BALB / c, exibem um desempenho superior em tarefas de aprendizagem e memória em comparação com outras estirpes, tais como o C57BL / 6 3. A F1 FVB / N x 129S6 fundo é utilizado para dois dos modelos mais utilizados de AD, o Tg2576 e RTG (TauP301L) 4.510 modelos. Esta estirpe exibe superiores capacidade de aprendizagem na MWM em relação a outras estirpes, incluindo B6 / SJL 4. Devido a esta capacidade de aprendizagem superior, o uso de uma única sonda após o treinamento extensivo pode mascarar diferenças entre os grupos resultantes de excesso de treinamento. Além disso, o sensitivity de ensaios de sondagem pode ser dependente da idade. Nós já haviam demonstrado que os ensaios anteriores da sonda, após o treinamento plataforma escondida limitado, são mais sensíveis às diferenças nas jovem Tg2576 em comparação com controles jovens da mesma ninhada de transgenes-negativos do que são ensaios sonda inserida após mais extensa formação 5. Em contraste, os ensaios seguintes sonda extensa formação são mais sensíveis em mais velho (20-25 meses) ratinhos Tg2576 em comparação com ninhada são maiores de ensaios de sondas anteriores 5. Por intercalando ensaios de sonda ao longo de formação, a probabilidade de que um ensaio sensível será identificado é aumentada, em particular se o teste é realizado longitudinal e a sensibilidade de um ensaio de sonda particular é dependente da idade. A Figura 1 mostra o desempenho superior de F1 FVB / N x camundongos 129S6 sob o protocolo otimizado para esta estirpe em comparação com os ratos do fundo B6 / SJL treinados sob um protocolo com a mais extensa formação. A MWM égeralmente pensado para fornecer medidas confiáveis ​​que são reproduzíveis através do tempo e laboratórios 6. Por exemplo, o protocolo primário usado originalmente por nosso laboratório 1,7 Minnesota foi implementado com sucesso com pequenas modificações na West Virginia University 8. Da mesma forma, níveis equivalentes de insuficiência foram observados em RTG (TauP301L) 4510 ratinhos relativamente ao controlo da mesma ninhada se alojados sob condições isentas de agentes patogénicos ou convencionais 9. No entanto, o ambiente de teste pode influenciar a sensibilidade da tarefa MWM. Fatores como a iluminação da sala, saídas de ar, gradientes de temperatura e ruídos, tudo contribui para estímulos ambientais 4 que em última instância pode influenciar o desempenho. Quando nosso laboratório Minnesota e biotério foram transferidos para um novo prédio, uma redução de até 38% no desempenho do tipo selvagem foi observado, reduzindo substancialmente o alcance dinâmico da tarefa ea capacidade de detectar déficits relacionados ao transgene. Esta mudança no performance ocorreu apesar projetar a sala de ensaios para ser do tamanho e configuração equivalente, e usando as mesmas indicações visuais aplicados. Um &quot;re-optimização&quot; do protocolo original foi necessária para aumentar a gama dinâmica da tarefa MWM no novo ambiente de teste. Aqui o protocolo original adaptado para uso com o F1 FVB / N x 129S6 fundo 5 está descrito. Uma vez que alguns estudos sugerem que o stress está associada com o mau desempenho MWM 10 e de pré-tratamento pode aliviar este défice induzido pelo stress no desempenho 11, um protocolo pré-tratamento foi concebido para aclimatar os ratos para a introdução e a remoção da piscina antes do teste MWM . Na sequência de pré-tratamento, os ratos submetidos a treinamento plataforma visível, em que uma plataforma elevada é marcado com uma bandeira. Formação plataforma visível é usado para identificar os ratos com problemas de desempenho relacionadas a anormalidades sensório-motoras. Usando critérios de exclusão descritos no protseção OCOL, os ratos-desempenho incompetente são removidos exames subseqüentes de ensaios de formação de plataforma e de sondas escondidas. Deficiências em ensaios de formação de plataforma e de sondas escondidas são interpretados como déficits cognitivos porque o desempenho sensório-motor é fatorado fora dos dados. Após a conclusão da formação plataforma visível, os ratinhos começam treino na plataforma escondida onde a plataforma está submersa em água e mantém-se na mesma posição em relação aos estímulos externos. Ensaios em que a plataforma é removida (ensaios de sonda) são intercaladas ao longo treino na plataforma escondida para avaliar a influência do treinamento adicional. Porque os ensaios de sonda ocorrer no início de cada dia, antes do treino adicional plataforma escondida, os ensaios de sonda medir a capacidade do animal para se lembrar a localização da plataforma depois de uma demora de 20 horas, considerado como uma medida da memória de referência 12. Finalmente, maneiras em que este protocolo original foi re-otimizado quando mudanças no ambiente de testedesempenho do controle interrompido são descritos.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Viewer Tracking software</td>
			<td>Biobserve</td>
			<td></td>
			<td>This particular software is not a requirement - there are other tracking systems available</td>
		</tr>
		<tr>
			<td>Pre-handling pool</td>
			<td></td>
			<td></td>
			<td>Dimensions approximately 1 foot wide x 2 feet long x 1.5 feet deep</td>
		</tr>
		<tr>
			<td>Plastic beaker</td>
			<td></td>
			<td></td>
			<td>1 liter</td>
		</tr>
		<tr>
			<td>Scoop</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Small net</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Stopwatch</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>White circular tub</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Non-toxic white tempera paint</td>
			<td></td>
			<td></td>
			<td>Any color can paint can be used; must completely cover the hidden platform</td>
		</tr>
		<tr>
			<td>Platform</td>
			<td></td>
			<td></td>
			<td>Color should contrast that of maze</td>
		</tr>
		<tr>
			<td>Curtain rod</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Curtains</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse performance tracking software</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Circular tub</td>
			<td></td>
			<td></td>
			<td>Uusally white in color; approximately 4 feet in diamater</td>
		</tr>
		<tr>
			<td>Platform</td>
			<td></td>
			<td></td>
			<td>Painted same color as the water</td>
		</tr>
	</tbody>
</table>

morris water maze test: optimization for mouse strain and testing environment

The Morris water maze (MWM) is a commonly used task to assess hippocampal-dependent spatial learning and memory in transgenic mouse models of disease, including neurocognitive disorders such as Alzheimer&#8217;s disease. However, the background strain of the mouse model used can have a substantial effect on the observed behavioral phenotype, with some strains exhibiting superior learning ability relative to others. To ensure differences between transgene negative and transgene positive mice can be detected, identification of a training procedure sensitive to the background strain is essential. Failure to tailor the MWM protocol to the background strain of the mouse model may lead to under- or over- training, thereby masking group differences in probe trials. Here, a MWM protocol tailored for use with the F1 FVB/N x 129S6 background is described. This is a frequently used background strain to study the age-dependent effects of mutant P301L tau (rTg(TauP301L)4510 mice) on the memory deficits associated with Alzheimer&#8217;s disease. Also described is a strategy to re-optimize, as dictated by the particular testing environment utilized.

Nós temos utilizado o labirinto de água de Morris para estudar os efeitos de beta-amilóide (Tg2576 ratinhos) e P301L mutante tau (RTG (TauP301L) 4510 ratinhos) na memória de referência espacial (por exemplo, 1,5,7,8). A Figura 3 é o resultado representativo consta em nosso estudo examinando o efeito do adulto-início expressão P301L tau no aprendizado e memória 8, utilizando testes de Meio Ambiente A. Para avaliar as capacidades motoras e visuais, os ratos foram co...

Watch this Scientific Journal Video about Morris Water Maze Test: Optimization for Mouse Strain and Testing Environment at JoVE.com

Morris Water Maze Test: Optimization for Mouse Strain and Testing Environment

This manuscript describes a Morris water maze (MWM) protocol tailored for use with a commonly used mouse model of Alzheimer's disease. The MWM is widely used in transgenic mouse models. Implementation of a procedure sensitive to the background strain of the mouse model is essential for detecting group differences.

Morris Water Maze Teste: Otimização para Mouse e Strain Testing Ambiente

 The Morris water maze (MWM) is a commonly used task to assess hippocampal-dependent spatial learning and memory in transgenic mouse models of disease, ...

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Behavior

21.3K visualizações.  West Virginia University.  This manuscript describes a Morris water maze (MWM) protocol tailored for use with a commonly used mouse model of Alzheimer's disease. The MWM is widely used in transgenic mouse models. Implementation of a procedure sensitive to the background strain of the mouse model is essential for detecting group differences. 

Vídeo: Morris Water Maze Test: Optimization for Mouse Strain and Testing Environment

Shallow Water (Paddling) Variants of Water Maze Tests in Mice

When Richard Morris devised his water maze in 19817, most behavioral work was done in rats. However, the greater understanding of mouse genetics led to the mouse becoming increasingly important. But researchers found that some strains of mutant mice were prone to problems like passively floating or diving when they were tested in the Morris water maze11. This was unsurprising considering their natural habitat; rats swim naturally (classically, the "sewer rat"), whereas mice evolved in the dry areas of central Asia.
To overcome these problems, it was considered whether shallow water would be a sufficient stimulus to provide escape motivation for mice. This would also avoid the problems of drying the small creatures with a towel and then putting them in a heated recovery chamber to avoid hypothermia, which is a much more serious problem than with rats; the large ratio of surface area to volume of a mouse makes it particularly vulnerable to rapid heat loss.
Another consideration was whether a more natural escape strategy could be used, to facilitate learning. Since animals that fall into water and swim away from the safety of the shore are unlikely to pass on their genes, animals have evolved a natural tendency to swim to the edge of a body of water. The Morris water maze, however, requires them to swim to a hidden platform towards the center of the maze - exactly opposite to their evolved behavior. Therefore the paddling maze should incorporate escape to the edge of the apparatus. This feature, coupled with the use of relatively non-aversive shallow water, embodies the "Refinement" aspect of the "3 Rs" of Russell and Burch8.
Various types of maze design were tried; the common feature was that the water was always shallow (2 cm deep) and escape was via a tube piercing the transparent wall of the apparatus. Other tubes ("false exits") were also placed around the walls but these were blocked off. From the inside of the maze all false exits and the single true exit looked the same. Currently a dodecagonal (12-sided) maze is in use in Oxford, with 12 true/false exits set in the corners. In a recent development a transparent paddling Y-maze has been tested successfully.

Shallow Water Paddling Variants of Water Maze Tests in Mice

Mice can swim, but many strains appear to find this activity stressful. To overcome this problem mazes have been devised where escape from shallow water is used to motivate behaviour. These have been demonstrated to support learning at least as good as the traditional and widely used Morris water maze.

Água (Palmatória) Variantes de água rasa testes de labirinto em ratos

When Richard Morris devised his water maze in 19817, most behavioral work was done in rats. However, the greater understanding of mouse genetics led to ...

Comportamento

Use of an Eight-arm Radial Water Maze to Assess Working and Reference Memory Following Neonatal Brain Injury

Working and reference memory are commonly assessed using the land based radial arm maze.&#160;However, this paradigm requires pretraining, food deprivation, and may introduce scent cue confounds. The eight-arm radial water maze is designed to evaluate reference and working memory performance simultaneously by requiring subjects to use extra-maze cues to locate escape platforms and remedies the limitations observed in land based radial arm maze designs. Specifically, subjects are required to avoid the arms previously used for escape during each testing day (working memory) as well as avoid the fixed arms, which never contain escape platforms (reference memory). Re-entries into arms that have already been used for escape during a testing session (and thus the escape platform has been removed) and re-entries into reference memory arms are indicative of working memory deficits. Alternatively, first entries into reference memory arms are indicative of reference memory deficits. We used this maze to compare performance of rats with neonatal brain injury and sham controls following induction of hypoxia-ischemia and show significant deficits in both working and reference memory after eleven days of testing. This protocol could be easily modified to examine many other models of learning impairment.

The eight-arm radial water maze is designed to evaluate reference and working memory performance simultaneously by requiring subjects to use extra-maze cues to locate escape platforms and remedies the limitations observed in land based radial arm maze designs.

Working and reference memory are commonly assessed using the land based radial arm maze.&#160;However, this paradigm requires pretraining, food ...

Barnes Maze Testing Strategies with Small and Large Rodent Models

Spatial learning and memory of laboratory rodents is often assessed via navigational ability in mazes, most popular of which are the water and dry-land (Barnes) mazes. Improved performance over sessions or trials is thought to reflect learning and memory of the escape cage/platform location. Considered less stressful than water mazes, the Barnes maze is a relatively simple design of a circular platform top with several holes equally spaced around the perimeter edge. All but one of the holes are false-bottomed or blind-ending, while one leads to an escape cage. Mildly aversive stimuli (e.g.&#160;bright overhead lights) provide motivation to locate the escape cage. Latency to locate the escape cage can be measured during the session; however, additional endpoints typically require video recording. From those video recordings, use of automated tracking software can generate a variety of endpoints that are similar to those produced in water mazes (e.g.&#160;distance traveled, velocity/speed, time spent in the correct quadrant, time spent moving/resting, and confirmation of latency). Type of search strategy (i.e.&#160;random, serial, or direct) can be categorized as well. Barnes maze construction and testing methodologies can differ for small rodents, such as mice, and large rodents, such as rats. For example, while extra-maze cues are effective for rats, smaller wild rodents may require intra-maze cues with a visual barrier around the maze. Appropriate stimuli must be identified which motivate the rodent to locate the escape cage. Both Barnes and water mazes can be time consuming as 4-7 test trials are typically required to detect improved learning and memory performance (e.g.&#160;shorter latencies or path lengths to locate the escape platform or cage) and/or differences between experimental groups. Even so, the Barnes maze is a widely employed behavioral assessment measuring spatial navigational abilities and their potential disruption by genetic, neurobehavioral manipulations, or drug/ toxicant exposure.

The dry-land Barnes maze is widely used to measure spatial navigation ability in response to mildly aversive stimuli. Over consecutive days, performance (e.g.&#160;latency to locate escape cage) of control subjects improves, indicative of normal learning and memory. Differences between rats and mice necessitate apparatus and methodology changes that are detailed here.

Barnes Estratégias Teste Labirinto com pequenas e grandes roedores Modelos

Spatial learning and memory of laboratory rodents is often assessed via navigational ability in mazes, most popular of which are the water and dry-land ...

The Double-H Maze: A Robust Behavioral Test for Learning and Memory in Rodents

Spatial cognition research in rodents typically employs the use of maze tasks, whose attributes vary from one maze to the next. These tasks vary by their behavioral flexibility and required memory duration, the number of goals and pathways, and also the overall task complexity. A confounding feature in many of these tasks is the lack of control over the strategy employed by the rodents to reach the goal, e.g., allocentric (declarative-like) or egocentric (procedural) based strategies. The double-H maze is a novel water-escape memory task that addresses this issue, by allowing the experimenter to direct the type of strategy learned during the training period. The double-H maze is a transparent device, which consists of a central alleyway with three arms protruding on both sides, along with an escape platform submerged at the extremity of one of these arms.
Rats can be trained using an allocentric strategy by alternating the start position in the maze in an unpredictable manner (see protocol 1; &#167;4.7), thus requiring them to learn the location of the platform based on the available allothetic cues. Alternatively, an egocentric learning strategy (protocol 2; &#167;4.8) can be employed by releasing the rats from the same position during each trial, until they learn the procedural pattern required to reach the goal. This task has been proven to allow for the formation of stable memory traces.
Memory can be probed following the training period in a misleading probe trial, in which the starting position for the rats alternates. Following an egocentric learning paradigm, rats typically resort to an allocentric-based strategy, but only when their initial view on the extra-maze cues differs markedly from their original position. This task is ideally suited to explore the effects of drugs/perturbations on allocentric/egocentric memory performance, as well as the interactions between these two memory systems.

The goal of this protocol is to investigate spatial cognition in rodents. The double-H water maze is a novel test, which is particularly useful to elucidate the different components of learning, consolidation and memory, as well as the interplay of memory systems.

O Double-H labirinto: um teste comportamental robusto para Aprendizado e Memória em roedores

Spatial cognition research in rodents typically employs the use of maze tasks, whose attributes vary from one maze to the next. These tasks vary by their ...

A Protocol for Housing Mice in an Enriched Environment

Environmental enrichment (EE) is a housing environment for mice that boosts mental and physical health compared to standard laboratory housing. Our recent studies demonstrate that environmental enrichment decreases adiposity, increases energy expenditure, resists diet induced obesity, and causes cancer remission and inhibition in mice. EE typically consists of larger living space, a variety of &#8216;toys&#8217; to interact with, running wheels, and can include a number of other novel environmental changes. All of this fosters a more complex social engagement, cognitive and physical stimulations. Importantly, the toy location and type of toy is changed regularly, which encourages the mice to adapt to a frequently changing and novel environment. Many variables can be manipulated in EE to promote health effects in mice. Thus these approaches are difficult to control and must be properly managed to successfully replicate the associated phenotypes. Therefore, the goal of this video is to demonstrate how EE is properly set up and maintained to assure a complex, challenging, and controlled environment so that other researchers can easily reproduce the protective effects of EE against obesity and cancer.

Environmental enrichment for mice requires a complex and challenging setup, as well as comprehensive husbandry and handling techniques to assure robust metabolic and anti-cancer effects in the mice. This protocol provides detailed procedures to reproduce the above mentioned effects in mice.

Um protocolo para alojar ratos em um ambiente enriquecido

Environmental enrichment (EE) is a housing environment for mice that boosts mental and physical health compared to standard laboratory housing. Our recent ...

The Treadmill Fatigue Test: A Simple, High-throughput Assay of Fatigue-like Behavior for the Mouse

Fatigue is a prominent symptom in many diseases and disorders and reduces quality of life for many people. The lack of clear pathogenesis and failure of current interventions to adequately treat fatigue in all patients leaves a need for new treatment options. Despite the therapeutic need and importance of preclinical research in helping identify promising novel treatments, few preclinical assays of fatigue are available. Moreover, the most common preclinical assay used to assess fatigue-like behavior, voluntary wheel running, is not suitable for use with some strains of mice, may not be sensitive to drugs that reduce fatigue, and has relatively low throughput. The current protocol describes a novel, non-voluntary preclinical assay of fatigue-like behavior, the treadmill fatigue test, and provides evidence of its efficacy in detecting fatigue-like behavior in mice treated with a chemotherapy drug known to cause fatigue in humans and fatigue-like behavior in animals. This assay may be a beneficial alternative to wheel running, as fatigue-like behavior and potential interventions can be assessed in a greater number of mice over a shorter time frame, thus permitting faster discovery of new therapeutic options.

Fatigue is a common, undertreated and frequently poorly-understood symptom in many diseases and disorders. New preclinical assays of fatigue may help to improve current understanding and future treatment of fatigue. To that end, the current protocol provides a novel means of measuring fatigue-like behavior in the mouse.

A esteira de fadiga de teste: Um ensaio simples, de alta taxa de transferência de Fadiga-like Comportamento para o Mouse

Fatigue is a prominent symptom in many diseases and disorders and reduces quality of life for many people. The lack of clear pathogenesis and failure of ...

Assessing Spatial Memory Impairment in a Mouse Model of Traumatic Brain Injury Using a Radial Water Tread Maze

Despite the recent increase in use of mouse models in scientific research, researchers continue to use cognitive tasks that were originally designed and validated for rat use. The Radial Water Tread (RWT) maze test of spatial memory (designed specifically for mice and requiring no swimming) has been shown previously to successfully distinguish between controlled cortical impact-induced TBI mice and sham controls. Here, a detailed protocol for this task is presented. The RWT maze capitalizes on the natural tendency of mice to avoid open areas in favor of hugging the sides of an apparatus (thigmotaxis). The walls of the maze are lined with nine escape holes placed above the floor of the apparatus, and mice are trained to use visual cues to locate the escape hole that leads out of the maze. The maze is filled with an inch of cold water, sufficient to motivate escape but not deep enough to require that the mouse swim. The acquisition period takes only four training days, with a test of memory retention on day five and a long-term memory test on day 12. The results reported here suggest that the RWT maze is a feasible alternative to rat-validated, swimming-based cognitive tests in the assessment of spatial memory deficits in mouse models of TBI.

Here we present a protocol for a mouse-specific test of cognition that does not require swimming. This test can be used to successfully distinguish controlled cortical impact-induced traumatic brain injury mice from sham controls.

Avaliando a insuficiência da memória espacial em um modelo de mouse de lesão cerebral traumática usando um labirinto de roda de água radial

Despite the recent increase in use of mouse models in scientific research, researchers continue to use cognitive tasks that were originally designed and ...

Testing Animal Anxiety in Rats: Effects of Open Arm Ledges and Closed Arm Wall Transparency in Elevated Plus Maze Test

The elevated plus maze test is a behavioral test for assessing animal anxiety in rodents. Although this test is widely applied in the field of behavioral science, conflicting outcomes are often provided from different laboratories. To identify reasons for the different outcomes, we previously focused on arm features, which differ between laboratories, most notably the presence/absence of ledges at the sides of open arms and the transparency/opaqueness of closed arm walls. In a previous report, we used a custom designed container to compare rat behavior on different combinations of open and closed arm designs under otherwise identical experimental conditions, and showed that differences in arm features interfere with experimental outcomes. In brief, open arm ledges significantly increased anxiety-like behavior in rats, while transparent arms may also have decreased this behavior. Furthermore, we verified a higher detection sensitivity of the effect of an anxiolytic drug in a combination of no-ledged open arm + opaque walled closed arm compared with a combination of ledged open arm + transparent walled closed arm. In this report, we introduce our protocol for the elevated plus maze test, together with discussion of the key results from the previous report and our experimental experience. We believe this report will provide useful information for researchers who have employed or who plan to use the elevated plus maze in their studies.

Rats' anxiety-like behavior tested by the elevated plus maze varies highly depending on the testing environment. Here we show how apparatus settings, especially arm structure, affect behavior on the maze, and we explain a reliable protocol to detect effects of anxiolytic drugs. This report will contribute to anxiety research.

Testes Animal ansiedade em ratos: efeitos de bordas de braço aberto e fechado do braço de parede transparência em elevados além de teste de labirinto

The elevated plus maze test is a behavioral test for assessing animal anxiety in rodents. Although this test is widely applied in the field of behavioral ...

Testing for Metacognitive Responding Using an Odor-based Delayed Match-to-Sample Test in Rats

Metamemory involves the cognitive ability to assess the strength of one&#39;s memories. To explore the possibility of metamemory in non-human animals, numerous behavioral tasks have been created, many of which utilize an option to decline memory tests. To assess metamemory in rats, we utilized this decline-test option paradigm by adapting previous visual delayed-match-to-sample tests (DMTS)1,2 developed for primate species to an odor-based test suitable for rodents. First,&#160;rats are given a sample to remember by digging in a cup of scented sand. After a delay, the rat is presented with four distinctly scented cups, one of which contains the identical scent experienced during the sample; if this matching cup is selected, then the rat obtains a preferred, larger reward. Selection of any of the other three non-matching sand-filled scented cups results in no reward. Retention intervals are individually titrated such that subjects perform between 40 and 70% correct, therefore ensuring rats sometimes remember and sometimes forget the sample. Here, the operational definition of metamemory is the ability to distinguish between the presence and absence of memory through behavioral responding. Towards this end, on two-thirds of trials, a decline option is presented in addition to the four choice cups (choice trials). If the decline-test option- an unscented colored sand cup, is selected, the subject receives a smaller less-preferred reward and avoids the memory test. On the remaining third of trials, the decline-test option is not available (forced trials), causing subjects to guess the correct cup when the sample is forgotten. On choice tests, subjects that know when they remember should select the decline option when memory is weak rather than take the test and choose incorrectly. Therefore, significantly higher performance on chosen tests as compared to forced memory tests is indicative of the adaptive use of the decline-test response and metacognitive responding.

This protocol describes a method for investigating the possibility of metamemory, or memory awareness, in rodents. The odor-based delayed-matching-to-sample paradigm is a novel, ecologically-relevant behavioral test useful for determining the extent to which rodents can adaptively respond based on cognitively monitoring the strength of their memory states.

Testes para responder metacognitiva usando um Odor baseado adiada partida-para-amostra teste em ratos

Metamemory involves the cognitive ability to assess the strength of one&#39;s memories. To explore the possibility of metamemory in non-human animals, ...

Measuring Active and Passive Tameness Separately in Mice

Domesticated animals such as dogs and laboratory mice show a high level of tameness, which is important for humans to handle them easily. Tameness has two behavioral components: a reluctance to avoid humans (passive tameness) and a motivation to approach humans (active tameness). To quantify these components in mice, we previously developed behavioral tests for active tameness, passive tameness, and the willingness to stay on a human hand, each designed to be completed within 3 min. The data obtained were used for selective breeding, with a large number of mice analyzed per generation. The active tameness test measures the movement of the mouse toward a human hand and the contact it engages in. The passive tameness test measures the duration of time that a mouse tolerates human touch. In the stay-on-hand test, a mouse is placed on a human hand and touched slowly using the thumb of that hand; the duration of time that the animal remains on the hand is measured. Here, we describe the test set-up and apparatus, explain the procedures, and discuss the appropriate data analysis. Finally, we explain how to interpret the results.

Tameness in animals includes a reduction of avoidance responses to humans (passive tameness) and an increase in active approaches to humans (active tameness). Here, we describe detailed protocols for three behavioral tests (active tameness, passive tameness, and stay-on-hand tests) to separately measure the active and passive tameness of mice.

Medição de ativa e passiva domesticidade separadamente em ratos

Domesticated animals such as dogs and laboratory mice show a high level of tameness, which is important for humans to handle them easily. Tameness has two ...