Os autores gostariam de agradecer prêmios salariais, subsídios de equipamentos e fundos operacionais das Fonds de la recherche en santé Québec (FRSQ), Canadian Institutes of Health Research (CIHR), Ciências Naturais e Pesquisa de Engenharia Council of Canada (NSERC), e da Concordia University Program Research Chairs (Cruc), bem como o feedback pensativo sobre este manuscrito do Dr. Jane Stewart.

1. Alojamento dos animais <ol><li> Cage: A fim de registrar a atividade corrida rodas de um roedor individual, cada gaiola deve abrigar um roedor e única corrida rodas. Porque rodas de corrida pode ser considerado uma forma de enriquecimento, todos os roedores em qualquer estudo devem ter acesso semelhante a uma roda de corrida. </li><li> Mudanças cama: manejo dos animais, bem como alterações em gaiolas ou roupa de cama todos podem ter não fóticos efeitos sobre os ritmos circadianos 21-23, assim, as gaiolas com malha de piso são ideais porque eles minimizar o contato com o animal. Não obstante a disponibilidade de tal uma bandeja de sistema, mudanças cama devem ser evitados durante fases críticas de um experimento. As alternativas incluem uso da cama mais duradouro, o que permitiria mais mudanças gaiola pouco frequentes, ou gaiolas de mudança em uma programação pseudo-aleatório. </li><li> Caixas de isolamento: gaiolas devem ser guardados em caixas de isolamento de som que são atenuadas, luz co-ntrolled, e bem ventilado. Dependendo do tamanho e configuração das caixas de isolamento, o número de gaiolas dentro de cada caixa variará tipicamente de 1-8. Quando abrigando várias gaiolas em uma caixa de isolamento único, um deve estar ciente de que vários odores e sons vindos de outros animais pode ter efeitos de confusão sobre o comportamento circadiano de animais individuais. Para evitar esses problemas, deve-se tentar abrigar uma gaiola por caixa de isolamento. </li><li> Ventilação: fluxo de ar adequado é fundamental para fazer as caixas de um ambiente confortável casa para roedores. O ventilador em cada caixa deve ser coberto, de modo a evitar que a luz de fora da área de atingir o interior. Além disso, os fãs vão tipicamente retirar o ar da caixa e explodi-lo para o quarto. Pequenas à prova de luz aberturas permitem a entrada de ar nas caixas de isolamento a partir de vários pontos, e ajuda a evitar brisas desconfortáveis. A fim de verificar se há ventilação adequada, a temperatura no interior da caixa de isolamento (quandofechado, durante várias horas, com as luzes acesas) deve ser virtualmente idêntico ao da temperatura da sala em que está inserido. </li><li> Iluminação: a intensidade da luz ambiente deve ser o mesmo em todas as jaulas. Organizar uma única luz em um local semelhante acima de cada gaiola, e use sempre a mesma marca / tipo de lâmpada. Use iluminação de intensidade moderada (100-300 lux) ao nível gaiola. Evite níveis de iluminação excessivamente altas, que são mais susceptíveis de produzir alterações diretas sobre o comportamento atribuíveis à luz em vez de o sistema circadiano, per se (máscara, por exemplo). </li><li> Escuridão / luz vermelha ofuscante: Se é necessário para tratar ou tratar os animais no escuro (por exemplo, na escuridão constante ou noturno), óculos de visão noturna deve ser usado. Alternativamente, porque o sistema circadiano é relativamente insensível ao vermelho-comprimentos de onda, a iluminação vermelha fraca pode ser usado. A luz vermelha específica que você usa deve ser testado para garantir que ele não Alter actividade corrida rodas (mascaramento, por exemplo) ou ajustar o relógio circadiano (por exemplo, produzir uma mudança de fase). </li></ol> 2. Coleta de dados (veja a Figura 1 - Vitalview configuração de hardware) <ol><li> Correndo rodas: o diâmetro ea ergonomia da roda de corrida irá mudar a quantidade de uso de 24. Assim, o uso rodas menores e mais leves para ratos, e maiores rodas mais pesadas para ratos. Ao lavar e re-instalar rodas, assegurar que as rodas são capazes de girar sem obstáculos, não &quot;cambalear&quot;, e que a gravação micro-interruptores são ativados por cada volta da roda. </li><li> Micro-chaves: cada revolução da roda de corrida deve ativar um magnético ou mecânico micro-interruptor. Informações do micro-interruptor é transmitido através de um canal único e registadas por um computador que pode bin os dados ao longo do tempo (por exemplo, a cada 2, 5, 6, ou 10 minutos). </li><li> Hardware do computador: Nossa running rodas gravações são feitas com Vitalview, uma plataforma de hardware e software desenvolvido pela Mini Mitter ( <a href="http://www.minimitter.com/vitalview_software.cfm" target="_blank">http://www.minimitter.com/vitalview_software.cfm</a> ). No entanto, existem outras plataformas de gravação, tais como ClockLab, desenvolvido pela Actimetrics ( <a href="http://www.actimetrics.com/ClockLab/" target="_blank">http://www.actimetrics.com/ClockLab/</a> ). Ambas as plataformas reunir dados de várias fontes de canal único (por exemplo, um micro-interruptor único ativado por uma única roda em execução) em um arquivo único computador. Os dados de canais individuais pode então ser representada e analisada separadamente numa data posterior. </li></ol> 3. Gravações de dados <ol><li> Arquivos: As plataformas de software acima mencionados podem ser usados ​​para separar canais únicos para que os arquivos individuais são criados para cada registro de funcionamento da roda. Esses dados são melhor visualizados e gráficos com especial designeprogramas tais como d ActiView (Minimitter, Bend, OR), Circadia ou Clocklab (Actimetrics, Wilmette, IL), que podem produzir e periodogramas actograms. No entanto, canal único arquivos também podem ser abertos e analisados ​​utilizando programas de planilhas gerais, tais como Excel (Microsoft, Redmond, WA). </li><li> Calculando Tempo Circadiano (TC): CT 12 é, por definição, o início da execução da roda-actividade em roedores noturnos. Em paralelo com o dia 24 hr, por convenção, um dia circadiano é dividido em 24 hr circadiano. Por conseguinte, se o período de funcionamento livre circadiano é 24 hr 30 min, medido pelo relógio de parede, CT 0 ocorrerá aproximadamente 12 h 15 min, depois CT12. </li></ol>

<ol>
	<li>Pittendrigh, C. S., Daan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Functional+Analysis+of+Circadian+Pacemakers+in+Nocturnal+Rodents.+V.+Pacemaker+Structure:+A+Clock+for+All+Seasons.">A Functional Analysis of Circadian Pacemakers in Nocturnal Rodents. V. Pacemaker Structure: A Clock for All Seasons.</a> J. Comp. Physiol. 106, 333-355 (1976).</li><li>Pittendrigh, C. S., Daan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Functional+Analysis+of+Circadian+Pacemakers+in+Nocturnal+Rodents.+IV.+Entrainment:+Pacemaker+as+Clock.">A Functional Analysis of Circadian Pacemakers in Nocturnal Rodents. IV. Entrainment: Pacemaker as Clock.</a> J. Comp. Physiol. 106, 291-331 (1976).</li><li>Pittendrigh, C. S., Daan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Functional+Analysis+of+Circadian+Pacemakers+in+Nocturnal+Rodents.+III.+Heavy+Water+and+Constant+Light:+Homeostasis+of+Frequency?.">A Functional Analysis of Circadian Pacemakers in Nocturnal Rodents. III. Heavy Water and Constant Light: Homeostasis of Frequency?.</a> J. Comp. Physiol. 106, 267-290 (1976).</li><li>Pittendrigh, C. S., Daan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Functional+Analysis+of+Circadian+Pacemakers+in+Nocturnal+Rodents.+II.+The+Variability+of+Phase+Response+Curves.">A Functional Analysis of Circadian Pacemakers in Nocturnal Rodents. II. The Variability of Phase Response Curves.</a> J. Comp. Physiol. 106, 253-266 (1976).</li><li>Pittendrigh, C. S., Daan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Functional+Analysis+of+Circadian+Pacemakers+in+Nocturnal+Rodents.+I.+The+Stability+and+Lability+of+Spontaneous+Frequency.">A Functional Analysis of Circadian Pacemakers in Nocturnal Rodents. I. The Stability and Lability of Spontaneous Frequency.</a> J. Comp. Physiol. 106, 223-252 (1976).</li><li>Ralph, M. R., Foster, R. G., Davis, F. C., Menaker, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transplanted+suprachiasmatic+nucleus+determines+circadian+period.">Transplanted suprachiasmatic nucleus determines circadian period.</a> Science. 247, 975-978 (1990).</li><li>Moore, R. Y., Eichler, V. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Loss+of+a+circadian+adrenal+corticosterone+rhythm+following+suprachiasmatic+lesions+in+the+rat.">Loss of a circadian adrenal corticosterone rhythm following suprachiasmatic lesions in the rat.</a> Brain Res. 42, 201-206 (1972).</li><li>Stephan, F. K., Zucker, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circadian+rhythms+in+drinking+behavior+and+locomotor+activity+of+rats+are+eliminated+by+hypothalamic+lesions.">Circadian rhythms in drinking behavior and locomotor activity of rats are eliminated by hypothalamic lesions.</a> Proc. Natl. Acad. Sci. U.S.A. 69, 1583-1586 (1972).</li><li>Abe, M., 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=Circadian+rhythms+in+isolated+brain+regions.">Circadian rhythms in isolated brain regions.</a> J. Neurosci. 22, 350-356 (2002).</li><li>Yamazaki, S., 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=Resetting+central+and+peripheral+circadian+oscillators+in+transgenic+rats.">Resetting central and peripheral circadian oscillators in transgenic rats.</a> Science. 288, 682-685 (2000).</li><li>Lamont, E. W., Robinson, B., Stewart, J., Amir, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+central+and+basolateral+nuclei+of+the+amygdala+exhibit+opposite+diurnal+rhythms+of+expression+of+the+clock+protein+Period2.">The central and basolateral nuclei of the amygdala exhibit opposite diurnal rhythms of expression of the clock protein Period2.</a> Proc. Natl. Acad. Sci. U.S.A. 102, 4180-4184 (2005).</li><li>Amir, S., Lamont, E. W., Robinson, B., Stewart, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+circadian+rhythm+in+the+expression+of+PERIOD2+protein+reveals+a+novel+SCN-controlled+oscillator+in+the+oval+nucleus+of+the+bed+nucleus+of+the+stria+terminalis.">A circadian rhythm in the expression of PERIOD2 protein reveals a novel SCN-controlled oscillator in the oval nucleus of the bed nucleus of the stria terminalis.</a> J. Neurosci. 24, 781-790 (2004).</li><li>Yoo, S. H., 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=PERIOD2::LUCIFERASE+real-time+reporting+of+circadian+dynamics+reveals+persistent+circadian+oscillations+in+mouse+peripheral+tissues.">PERIOD2::LUCIFERASE real-time reporting of circadian dynamics reveals persistent circadian oscillations in mouse peripheral tissues.</a> Proc. Natl. Acad. Sci. U.S.A. 101, 5339-5346 (2004).</li><li>Guilding, C., Piggins, H. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Challenging+the+omnipotence+of+the+suprachiasmatic+timekeeper:+are+circadian+oscillators+present+throughout+the+mammalian+brain?.">Challenging the omnipotence of the suprachiasmatic timekeeper: are circadian oscillators present throughout the mammalian brain?.</a> Eur. J. Neurosci. 25, 3195-3216 (2007).</li><li>Boulos, Z., Terman, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Food+availability+and+daily+biological+rhythms.">Food availability and daily biological rhythms.</a> Neurosci. Biobehav. Rev. 4, 119-131 (1980).</li><li>Boulos, Z., Rosenwasser, A. M., Terman, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Feeding+schedules+and+the+circadian+organization+of+behavior+in+the+rat.">Feeding schedules and the circadian organization of behavior in the rat.</a> Behav. Brain Res. 1, 39-65 (1980).</li><li>Verwey, M., Amir, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Food-entrainable+circadian+oscillators+in+the+brain.">Food-entrainable circadian oscillators in the brain.</a> Eur. J. Neurosci. 30, 1650-1657 (2009).</li><li>Davidson, A. J., Poole, A. S., Yamazaki, S., Menaker, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Is+the+food-entrainable+circadian+oscillator+in+the+digestive+system?.">Is the food-entrainable circadian oscillator in the digestive system?.</a> Genes Brain Behav. 2, 32-39 (2003).</li><li>Hara, R., 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=Restricted+feeding+entrains+liver+clock+without+participation+of+the+suprachiasmatic+nucleus.">Restricted feeding entrains liver clock without participation of the suprachiasmatic nucleus.</a> Genes Cells. 6, 269-278 (2001).</li><li>Damiola, F., 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=Restricted+feeding+uncouples+circadian+oscillators+in+peripheral+tissues+from+the+central+pacemaker+in+the+suprachiasmatic+nucleus.">Restricted feeding uncouples circadian oscillators in peripheral tissues from the central pacemaker in the suprachiasmatic nucleus.</a> Genes Dev. 14, 2950-2961 (2000).</li><li>Mrosovsky, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phase+response+curves+for+social+entrainment.">Phase response curves for social entrainment.</a> J. Comp. Physiol. A. 162, 35-46 (1988).</li><li>Cain, S. W., 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=Reward+and+aversive+stimuli+produce+similar+nonphotic+phase+shifts.">Reward and aversive stimuli produce similar nonphotic phase shifts.</a> Behav. Neurosci. 118, 131-137 (2004).</li><li>Antle, M. C., Mistlberger, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circadian+clock+resetting+by+sleep+deprivation+without+exercise+in+the+Syrian+hamster.">Circadian clock resetting by sleep deprivation without exercise in the Syrian hamster.</a> J. Neurosci. 20, 9326-9332 (2000).</li><li>Banjanin, S., Mrosovsky, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preferences+of+mice,+Mus+musculus,+for+different+types+of+running+wheel.">Preferences of mice, Mus musculus, for different types of running wheel.</a> Lab Anim. 34, 313-318 (2000).</li><li>Verwey, M., Lam, G. Y., Amir, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circadian+rhythms+of+PERIOD1+expression+in+the+dorsomedial+hypothalamic+nucleus+in+the+absence+of+entrained+food-anticipatory+activity+rhythms+in+rats.">Circadian rhythms of PERIOD1 expression in the dorsomedial hypothalamic nucleus in the absence of entrained food-anticipatory activity rhythms in rats.</a> Eur. J. Neurosci. 29, 2217-2222 (2009).</li><li>Gooley, J. J., Schomer, A., Saper, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+dorsomedial+hypothalamic+nucleus+is+critical+for+the+expression+of+food-entrainable+circadian+rhythms.">The dorsomedial hypothalamic nucleus is critical for the expression of food-entrainable circadian rhythms.</a> Nat. Neurosci. 9, 398-407 (2006).</li></ol>

Não há conflitos de interesse declarados.

Monitoramento ritmos de actividade diária usando rodas de corrida é o método mais utilizado e confiável para avaliar a saída do relógio circadiano mestre em roedores noturnos. Roda de rodagem de actividade, no entanto, é apenas um dos muitos aspectos do comportamento e fisiologia que pode ser monitorado continuamente. Embora a grande maioria de corrida rodas actividade ocorre durante a noite, ao longo de 30% do total de vigília ocorre durante o dia 25,26. Outros parâmetros podem ser usados ​​para...

<table border="1"&gt;<tbody&gt;<tr&gt;<td<strong&gt; Nome do reagente</strong</td&gt;<td<strong&gt; Empresa</strong</td&gt;<td<strong&gt; Número de catálogo</strong</td&gt;<td<strong&gt; Comentários (opcional)</strong</td&gt;</tr&gt;<tr&gt;<td&gt; Vitalview Card &amp; Software</td&gt;<td&gt; Mini Mitter</td&gt;<td&gt; # 855-0030-00</td&gt;<td&gt; (Bend, OR, EUA)</td&gt;</tr&gt;<tr&gt;<td&gt; DP24 Dataport</td&gt;<td&gt; Mini Mitter</td&gt;<td&gt; # 840-0024-00</td&gt;<td&gt; (Bend, OR, EUA)</td&gt;</tr&gt;<tr&gt;<td&gt; QA4 Módulo</td&gt;<td&gt; Mini Mitter</td&gt;<td&gt; # 130-0050-00</td&gt;<td&gt; (Bend, OR, EUA)</td&gt;</tr&gt;<tr&gt;<td&gt; Chave Magnética</td&gt;<td&gt; Mini Mitter</td&gt;<td&gt; # 130-0015-00</td&gt;<td&gt; (Bend, OR, EUA)</td&gt;</tr&gt;<tr&gt;<td&gt; Montagem C-50 Cable</td&gt;<td&gt; Mini Mitter</td&gt;<td&gt; # 060-0045-10</td&gt;<td&gt; (Bend, OR, EUA)</td&gt;</tr&gt;<tr&gt;<td&gt; Rato correndo conjunto da roda</td&gt;<td&gt; Mini Mitter</td&gt;<td&gt; # 640-0700-00</td&gt;<td&gt; (Bend, OR, EUA)</td&gt;</tr&gt;<tr&gt;<td&gt; Apoio Cage e bandeja</td&gt;<td&gt; Mini Mitter</td&gt;<td&gt; # 640-0400-00</td&gt;<td&gt; (Bend, OR, EUA)</td&gt;</tr&gt;<tr&gt;<td&gt; Utilizável cortar gaiola</td&gt;<td&gt; Mini Mitter</td&gt;<td&gt; # 664-2154-00</td&gt;<td&gt; (Bend, OR, EUA)</td&gt;</tr&gt;<tr&gt;<td&gt; Piso de grade para gaiola</td&gt;<td&gt; Mini Mitter</td&gt;<td&gt; # 676-2154-00</td&gt;<td&gt; (Bend, OR, EUA)</td&gt;</tr&gt;<tr&gt;<td&gt; Bandeja de Resíduos</td&gt;<td&gt; Mini Mitter</td&gt;<td&gt; # 684-2154-00</td&gt;<td&gt; (Bend, OR, EUA)</td&gt;</tr&gt;<tr&gt;<td&gt; Lâmpada habitação</td&gt;<td&gt; Microlitos Científico</td&gt;<td&gt; # R-101</td&gt;<td&gt; (Toronto, ON, Canadá)</td&gt;</tr&gt;<tr&gt;<td&gt; 4V lâmpadas fluorescentes</td&gt;<td&gt; Microlitos Científico</td&gt;<td&gt; # F4T5/CW</td&gt;<td&gt; (Toronto, ON, Canadá)</td&gt;</tr&gt;<tr&gt;<td&gt; Isolamento câmaras</td&gt;<td&gt; Custom construído</td&gt;<td</td&gt;<td&gt; 28 &quot;H x 20&quot; W x 28 &quot;D ½&quot; Black melamina.</td&gt;</tr&gt;</tbody&gt;</table

recording and analysis of circadian rhythms in running-wheel activity in rodents

Quando os roedores têm acesso livre a uma roda de corrida em sua gaiola, uso voluntário desta roda vai depender da hora do dia 1-5. Roedores noturnos, incluindo ratos, hamsters e ratos, são ativos durante a noite e relativamente inativo durante o dia. Muitas outras medidas comportamentais e fisiológicas também apresentam ritmos diários, mas em roedores, correndo rodas actividade serve como uma medida particularmente fiável e conveniente da saída do relógio circadiano mestre, o núcleo supraquiasmático (SCN) do hipotálamo. De um modo geral, por meio de um processo chamado de arrastamento, o padrão diário de execução rodas actividade irá, naturalmente, se alinham com o ciclo de claro-escuro do ambiente (ciclo LD; por exemplo, 12 horas de luz: 12 h-escuro). No entanto ritmos circadianos são gerados endogenamente padrões de comportamento que apresentam um período de ~ 24 horas, e persistem na escuridão constante. Assim, na ausência de um ciclo LD, a gravação e análise de funcionamento da roda-actividade podeser utilizado para determinar o tempo subjectivo do dia. Porque estes ritmos são dirigidos pelo relógio circadiano no subjectivo da hora do dia, é referido como o tempo circadiano (CT). Em contraste, quando um ciclo LD está presente, a hora do dia, isto é determinado pelo ciclo LD ambiental é chamado o tempo zeitgeber (ZT). Embora os ritmos circadianos em funcionamento roda-atividade são geralmente ligados ao relógio SCN 6-8, osciladores circadianos em muitas outras regiões do cérebro e do corpo 9-14 também poderiam estar envolvidos na regulação dos ritmos de actividade diária. Por exemplo, ritmos diários de alimentos antecipatória actividade não requerem o SCN 15,16 e em vez disso, estão correlacionadas com alterações na actividade de SCN-extra osciladores 17-20. Assim, as gravações de execução rodas actividade pode fornecer informação comportamental importante, não só sobre a saída do relógio mestre SCN, mas também da actividade de SCN-extra osciladores. Abaixo descrIBE o equipamento e os métodos utilizados para registrar, analisar e exibir ritmos circadianos de atividade locomotora em roedores de laboratório.

<ol><li> Programas de computador: programas de computador especializados são normalmente utilizados na geração de actograms e do cálculo do período circadiano. Estes programas incluem, mas não estão limitados a, ActiView (Minimitter, Bend, OR) e Circadia. </li><li> Actograms: Actograms fornecer uma ilustração gráfica dos padrões diários de funcionamento da roda-actividade. Há um único traçado (eixo x = 24 h) e duplo traçado (eixo x = 48 h) actograms. Ambos os métodos dias enredo seqüenciais de...

Watch this Scientific Journal Video about Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents at JoVE.com

Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents

Ritmos circadianos voluntária rodas execução de atividade em mamíferos está intimamente ligado às oscilações moleculares de um relógio mestre no cérebro. Como tal, estes ritmos diários de comportamento pode ser utilizado para estudar a influência dos factores genéticos, farmacológicos e ambientais sobre o funcionamento deste relógio circadiano.

Registro e análise dos ritmos circadianos em Running rodas Atividade em Roedores

When rodents have free access to a running wheel in their home cage, voluntary use of this wheel will depend on the time of day1-5. Nocturnal rodents, ...

recording-analysis-circadian-rhythms-running-wheel-activity

Research

JoVE Journal

Neuroscience

21.1K visualizações.  McGill University. Ritmos circadianos voluntária rodas execução de atividade em mamíferos está intimamente ligado às oscilações moleculares de um relógio mestre no cérebro. Como tal, estes ritmos diários de comportamento pode ser utilizado para estudar a influência dos factores genéticos, farmacológicos e ambientais sobre o funcionamento deste relógio circadiano.

Vídeo: Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents

Assaying Locomotor Activity to Study Circadian Rhythms and Sleep Parameters in Drosophila

Most life forms exhibit daily rhythms in cellular, physiological and behavioral phenomena that are driven by endogenous circadian (&equiv;24 hr) pacemakers or clocks. Malfunctions in the human circadian system are associated with numerous diseases or disorders. Much progress towards our understanding of the mechanisms underlying circadian rhythms has emerged from genetic screens whereby an easily measured behavioral rhythm is used as a read-out of clock function. Studies using Drosophila have made seminal contributions to our understanding of the cellular and biochemical bases underlying circadian rhythms. The standard circadian behavioral read-out measured in Drosophila is locomotor activity. In general, the monitoring system involves specially designed devices that can measure the locomotor movement of Drosophila. These devices are housed in environmentally controlled incubators located in a darkroom and are based on using the interruption of a beam of infrared light to record the locomotor activity of individual flies contained inside small tubes. When measured over many days, Drosophila exhibit daily cycles of activity and inactivity, a behavioral rhythm that is governed by the animal's endogenous circadian system. The overall procedure has been simplified with the advent of commercially available locomotor activity monitoring devices and the development of software programs for data analysis. We use the system from Trikinetics Inc., which is the procedure described here and is currently the most popular system used worldwide. More recently, the same monitoring devices have been used to study sleep behavior in Drosophila. Because the daily wake-sleep cycles of many flies can be measured simultaneously and only 1 to 2 weeks worth of continuous locomotor activity data is usually sufficient, this system is ideal for large-scale screens to identify Drosophila manifesting altered circadian or sleep properties.

Assaying Locomotor Activity to Study Circadian Rhythms and Sleep Parameters in Drosophila

We describe procedures for recording daily locomotor activity rhythms of Drosophila and subsequent data analysis. Locomotor activity rhythms are a reliable behavioral output of animal circadian clocks and are used as the standard readout of clock function when studying circadian mutants or examining how the environment regulates the circadian system.

Assaying atividade locomotora para estudar ritmos circadianos e sono Parâmetros em Drosophila</em

Most life forms exhibit daily rhythms in cellular, physiological and behavioral phenomena that are driven by endogenous circadian (&equiv;24 hr) ...

Neurociência

Measuring Circadian and Acute Light Responses in Mice using Wheel Running Activity

Circadian rhythms are physiological functions that cycle over a period of approximately 24 hours (circadian- circa: approximate and diem: day)1, 2. They are responsible for timing our sleep/wake cycles and hormone secretion. Since this timing is not precisely 24-hours, it is synchronized to the solar day by light input. This is accomplished via photic input from the retina to the suprachiasmatic nucleus (SCN) which serves as the master pacemaker synchronizing peripheral clocks in other regions of the brain and peripheral tissues to the environmental light dark cycle3-7. The alignment of rhythms to this environmental light dark cycle organizes particular physiological events to the correct temporal niche, which is crucial for survival8. For example, mice sleep during the day and are active at night. This ability to consolidate activity to either the light or dark portion of the day is referred to as circadian photoentrainment and requires light input to the circadian clock9. Activity of mice at night is robust particularly in the presence of a running wheel. Measuring this behavior is a minimally invasive method that can be used to evaluate the functionality of the circadian system as well as light input to this system. Methods that will covered here are used to examine the circadian clock, light input to this system, as well as the direct influence of light on wheel running behavior.

This article will review methods that can be used to determine circadian function and light responsiveness in mice.

Medição Responses Luz circadianos e aguda em ratos usando Atividade Roda Executando

Circadian rhythms are physiological functions that cycle over a period of approximately 24 hours (circadian- circa: approximate and diem: day)1, 2.  They ...

Large-scale Recording of Neurons by Movable Silicon Probes in Behaving Rodents

A major challenge in neuroscience is linking behavior to the collective activity of neural assemblies. Understanding of input-output relationships of neurons and circuits requires methods with the spatial selectivity and temporal resolution appropriate for mechanistic analysis of neural ensembles in the behaving animal, i.e. recording of representatively large samples of isolated single neurons. Ensemble monitoring of neuronal activity has progressed remarkably in the past decade in both small and large-brained animals, including human subjects1-11. Multiple-site recording with silicon-based devices are particularly effective because of their scalability, small volume and geometric design.
Here, we describe methods for recording multiple single neurons and local field potential in behaving rodents, using commercially available micro-machined silicon probes with custom-made accessory components. There are two basic options for interfacing silicon probes to preamplifiers: printed circuit boards and flexible cables. Probe supplying companies (<a href="http://www.neuronexustech.com/" >http://www.neuronexustech.com/</a>; <a href="http://www.sbmicrosystems.com/">http://www.sbmicrosystems.com/</a>; <a href="http://www.acreo.se/">http://www.acreo.se/</a>) usually provide the bonding service and deliver probes bonded to printed circuit boards or flexible cables. Here, we describe the implantation of a 4-shank, 32-site probe attached to flexible polyimide cable, and mounted on a movable microdrive. Each step of the probe preparation, microdrive construction and surgery is illustrated so that the end user can easily replicate the process.

We describe methods for large-scale recording of multiple single units and local field potential in behaving rodents with silicon probes. Drive fabrication, probe attachment to the drive and probe implantation processes are illustrated in sufficient details for easy replication.

Em larga escala de gravação de Neurônios por sondas de silicone móveis em Comportando Roedores

A major challenge in neuroscience is linking behavior to the collective activity of neural assemblies. Understanding of input-output relationships of ...

A Fully Automated and Highly Versatile System for Testing Multi-cognitive Functions and Recording Neuronal Activities in Rodents

We have developed a fully automated system for operant behavior testing and neuronal activity recording by which multiple cognitive brain functions can be investigated in a single task sequence. The unique feature of this system is a custom-made, acoustically transparent chamber that eliminates many of the issues associated with auditory cue control in most commercially available chambers. The ease with which operant devices can be added or replaced makes this system quite versatile, allowing for the implementation of a variety of auditory, visual, and olfactory behavioral tasks. Automation of the system allows fine temporal (10 ms) control and precise time-stamping of each event in a predesigned behavioral sequence. When combined with a multi-channel electrophysiology recording system, multiple cognitive brain functions, such as motivation, attention, decision-making, patience, and rewards, can be examined sequentially or independently.

In this report, we present a fully automated and highly versatile system capable of simultaneously testing multi-cognitive behaviors and recording neuronal activities for rodents.

Um sistema totalmente automatizado e altamente versátil para testes de várias funções cognitivas e registro das atividades neuronais em roedores

We have developed a fully automated system for operant behavior testing and neuronal activity recording by which multiple cognitive brain functions can be ...

Retrograde Fluorescent Labeling Allows for Targeted Extracellular Single-unit Recording from Identified Neurons In vivo

The overall goal of this method is to record single-unit responses from an identified population of neurons. In vivo electrophysiological recordings from individual neurons are critical for understanding how neural circuits function under natural conditions. Traditionally, these recordings have been performed 'blind', meaning the identity of the recorded cell is unknown at the start of the recording. Cellular identity can be subsequently determined via intracellular1, juxtacellular2 or loose-patch3 iontophoresis of dye, but these recordings cannot be pre-targeted to specific neurons in regions with functionally heterogeneous cell types. Fluorescent proteins can be expressed in a cell-type specific manner permitting visually-guided single-cell electrophysiology4-6. However, there are many model systems for which these genetic tools are not available. Even in genetically accessible model systems, the desired promoter may be unknown or genetically homogenous neurons may have varying projection patterns. Similarly, viral vectors have been used to label specific subgroups of projection neurons7, but use of this method is limited by toxicity and lack of trans-synaptic specificity. Thus, additional techniques that offer specific pre-visualization to record from identified single neurons in vivo are needed. Pre-visualization of the target neuron is particularly useful for challenging recording conditions, for which classical single-cell recordings are often prohibitively difficult8-11. The novel technique described in this paper uses retrograde transport of a fluorescent dye applied using tungsten needles to rapidly and selectively label a specific subset of cells within a particular brain region based on their unique axonal projections, thereby providing a visual cue to obtain targeted electrophysiological recordings from identified neurons in an intact circuit within a vertebrate CNS.
The most significant novel advancement of our method is the use of fluorescent labeling to target specific cell types in a non-genetically accessible model system. Weakly electric fish are an excellent model system for studying neural circuits in awake, behaving animals12. We utilized this technique to study sensory processing by "small cells" in the anterior exterolateral nucleus (ELa) of weakly electric mormyrid fish. "Small cells" are hypothesized to be time comparator neurons important for detecting submillisecond differences in the arrival times of presynaptic spikes13. However, anatomical features such as dense myelin, engulfing synapses, and small cell bodies have made it extremely difficult to record from these cells using traditional methods11, 14. Here we demonstrate that our novel method selectively labels these cells in 28% of preparations, allowing for reliable, robust recordings and characterization of responses to electrosensory stimulation.

Retrograde Fluorescent Labeling Allows for Targeted Extracellular Single-unit Recording from Identified Neurons In vivo

Retrograde transport of fluorescent dye labels a sub-population of neurons based on anatomical projection. Labeled axons can be visually targeted in vivo, permitting extracellular recording from identified axons. This technique facilitates recording when neurons cannot be labeled through genetic manipulation or are difficult to isolate using 'blind' in vivo approaches.

Labeling fluorescentes retrógrada Permite alvejado Extracelular Gravação Single-unidade dos neurônios identificados<em&gt; In vivo</em

The overall goal of this method is to record single-unit responses from an identified population of neurons. In vivo electrophysiological recordings from ...

Multi-unit Recording Methods to Characterize Neural Activity in the Locust (Schistocerca Americana) Olfactory Circuits

Detection and interpretation of olfactory cues are critical for the survival of many organisms. Remarkably, species across phyla have strikingly similar olfactory systems suggesting that the biological approach to chemical sensing has been optimized over evolutionary time1. In the insect olfactory system, odorants are transduced by olfactory receptor neurons (ORN) in the antenna, which convert chemical stimuli into trains of action potentials. Sensory input from the ORNs is then relayed to the antennal lobe (AL; a structure analogous to the vertebrate olfactory bulb). In the AL, neural representations for odors take the form of spatiotemporal firing patterns distributed across ensembles of principal neurons (PNs; also referred to as projection neurons)2,3. The AL output is subsequently processed by Kenyon cells (KCs) in the downstream mushroom body (MB), a structure associated with olfactory memory and learning4,5. Here, we present electrophysiological recording techniques to monitor odor-evoked neural responses in these olfactory circuits.
First, we present a single sensillum recording method to study odor-evoked responses at the level of populations of ORNs6,7. We discuss the use of saline filled sharpened glass pipettes as electrodes to extracellularly monitor ORN responses. Next, we present a method to extracellularly monitor PN responses using a commercial 16-channel electrode3. A similar approach using a custom-made 8-channel twisted wire tetrode is demonstrated for Kenyon cell recordings8. We provide details of our experimental setup and present representative recording traces for each of these techniques.

Multi-unit Recording Methods to Characterize Neural Activity in the Locust Schistocerca Americana Olfactory Circuits

We demonstrate variations of the extracellular multi-unit recording technique to characterize odor-evoked responses in the first three stages of the invertebrate olfactory pathway. These techniques can easily be adapted to examine ensemble activity in other neural systems as well.

Multi-unidade Métodos de gravação para caracterizar a atividade neural no Locust (<em&gt; Schistocerca Americana</em&gt;) Circuitos olfatórias

Detection and interpretation of olfactory cues are critical for the survival  of many organisms. Remarkably, species across phyla have strikingly similar ...

Deep Brain Stimulation with Simultaneous fMRI in Rodents

In order to visualize the global and downstream neuronal responses to deep brain stimulation (DBS) at various targets, we have developed a protocol for using blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) to image rodents with simultaneous DBS. DBS fMRI presents a number of technical challenges, including accuracy of electrode implantation, MR artifacts created by the electrode, choice of anesthesia and paralytic to minimize any neuronal effects while simultaneously eliminating animal motion, and maintenance of physiological parameters, deviation from which can confound the BOLD signal.&#160;Our laboratory has developed a set of procedures that are capable of overcoming most of these possible issues. For electrical stimulation, a homemade tungsten bipolar microelectrode is used, inserted stereotactically at the stimulation site in the anesthetized subject. In preparation for imaging, rodents are fixed on a plastic headpiece and transferred to the magnet bore. For sedation and paralysis during scanning, a cocktail of dexmedetomidine and pancuronium is continuously infused, along with a minimal dose of isoflurane; this preparation minimizes the BOLD ceiling effect of volatile anesthetics. In this example experiment, stimulation of the subthalamic nucleus (STN) produces BOLD responses which are observed primarily in ipsilateral cortical regions, centered in motor cortex. Simultaneous DBS and fMRI allows the unambiguous modulation of neural circuits dependent on stimulation location and stimulation parameters, and permits observation of neuronal modulations free of regional bias. This technique may be used to explore the downstream effects of modulating neural circuitry at nearly any brain region, with implications for both experimental and clinical DBS.

This protocol describes a standard method for simultaneous functional magnetic resonance imaging and deep brain stimulation in the rodent. The combined use of these experimental tools allows for the exploration of global downstream activity in response to electrical stimulation at virtually any brain target.

Estimulação Cerebral Profunda com fMRI simultâneo em Roedores

In order to visualize the global and downstream neuronal responses to deep brain stimulation (DBS) at various targets, we have developed a protocol for ...

In Vitro Recording of Mesenteric Afferent Nerve Activity in Mouse Jejunal and Colonic Segments

Afferent nerves not only convey information concerning normal physiology, but also signal disturbed homeostasis and pathophysiological processes of the different organ systems from the periphery towards the central nervous system. As such, the increased activity or &#39;sensitization&#39; of mesenteric afferent nerves has been allocated an important role in the pathophysiology of visceral hypersensitivity and abdominal pain syndromes.
Mesenteric afferent nerve activity can be measured in vitro in an isolated intestinal segment that is mounted in a purpose-built organ bath and from which the splanchnic nerve is isolated, allowing researchers to directly assess nerve activity adjacent to the gastrointestinal segment. Activity can be recorded at baseline in standardized conditions, during distension of the segment or following the addition of pharmacological compounds delivered intraluminally or serosally. This technique allows the researcher to easily study the effect of drugs targeting the peripheral nervous system in control specimens; besides, it provides crucial information on how neuronal activity is altered during disease. It should be noted however that measuring afferent neuronal firing activity only constitutes one relay station in the complex neuronal signaling cascade, and researchers should bear in mind not to overlook neuronal activity at other levels (e.g., dorsal root ganglia, spinal cord or central nervous system) in order to fully elucidate the complex neuronal physiology in health and disease.
Commonly used applications include the study of neuronal activity in response to the administration of lipopolysaccharide, and the study of afferent nerve activity in animal models of irritable bowel syndrome. In a more translational approach, the isolated mouse intestinal segment can be exposed to colonic supernatants from IBS patients. Furthermore, a modification of this technique has been recently shown to be applicable in human colonic specimens.

In Vitro Recording of Mesenteric Afferent Nerve Activity in Mouse Jejunal and Colonic Segments

Mesenteric afferent nerves convey information from the gastrointestinal tract towards the brain regarding normal homeostasis as well as pathophysiology. Gastrointestinal afferent nerve activity can be assessed by mounting isolated intestinal segments with attached afferent nerves into an organ bath, isolating the nerve, and assessing basal as well as stimulated activity.

In Vitro A gravação de mesentérica aferentes a atividade do nervo no mouse jejuno e segmentos do cólon

Afferent nerves not only convey information concerning normal physiology, but also signal disturbed homeostasis and pathophysiological processes of the ...

Preparations and Protocols for Whole Cell Patch Clamp Recording of Xenopus laevis Tectal Neurons

The Xenopus tadpole retinotectal circuit, comprised of the retinal ganglion cells (RGCs) in the eye which form synapses directly onto neurons in the optic tectum, is a popular model to study how neural circuits self-assemble. The ability to carry out whole cell patch clamp recordings from tectal neurons and to record RGC-evoked responses, either in vivo or using a whole brain preparation, has generated a large body of high-resolution data about the mechanisms underlying normal, and abnormal, circuit formation and function. Here we describe how to perform the in vivo preparation, the original whole brain preparation, and a more recently developed horizontal brain slice preparation for obtaining whole cell patch clamp recordings from tectal neurons. Each preparation has unique experimental advantages. The in vivo preparation enables the recording of the direct response of tectal neurons to visual stimuli projected onto the eye. The whole brain preparation allows for the RGC axons to be activated in a highly controlled manner, and the horizontal brain slice preparation allows recording from across all layers of the tectum.

Preparations and Protocols for Whole Cell Patch Clamp Recording of Xenopus laevis Tectal Neurons

In this paper, we discuss three brain preparations used for whole cell patch clamp recording to study the retinotectal circuit of Xenopus laevis tadpoles. Each preparation, with its own specific advantages, contributes to the experimental tractability of the Xenopus tadpole as a model to study neural circuit function.

Preparações e protocolos para toda célula Patch Clamp gravação de neurônios Tectal Xenopus laevis

The Xenopus tadpole retinotectal circuit, comprised of the retinal ganglion cells (RGCs) in the eye which form synapses directly onto neurons in the optic ...

The Power of Interstimulus Interval for the Assessment of Temporal Processing in Rodents

Temporal processing deficits have been implicated as a potential elemental dimension of higher-level cognitive processes, commonly observed in neurocognitive disorders. Despite the popularization of prepulse inhibition (PPI) in recent years, many current protocols promote using a percent of control measure, thereby precluding the assessment of temporal processing. The present study used cross-modal PPI and gap prepulse inhibition (gap-PPI) to demonstrate the benefits of employing a range of interstimulus intervals (ISIs) to delineate effects of sensory modality, psychostimulant exposure, and age. Assessment of sensory modality, psychostimulant exposure, and age reveals the utility of an approach varying the interstimulus interval (ISI) to establish the shape of the ISI function, including increases (sharper curve inflections) or decreases (flattening of the response amplitude curve) in startle amplitude. Additionally, shifts in peak response inhibition, suggestive of a differential sensitivity to the manipulation of ISI, are often revealed. Thus, the systematic manipulation of ISI affords a critical opportunity to evaluate temporal processing, which may reveal the underlying neural mechanisms involved in neurocognitive disorders.

Temporal processing, a preattentive process, may underlie deficits in higher-level cognitive processes, including attention, commonly observed in neurocognitive disorders. Using prepulse inhibition as an exemplar paradigm, we present a protocol for manipulating interstimulus interval (ISI) to establish the shape of the ISI function to provide an assessment of temporal processing.