Name: urokinase-type plasminogen activator-induced mouse back pain model
Uploaded: 2023-09-01T12:00:00
Description: Watch this Scientific Journal Video about Urokinase-type Plasminogen Activator-induced Mouse Back Pain Model at JoVE.com

O financiamento da subvenção foi fornecido pelo NIH HEAL UG3 NS123958. As instalações habitacionais foram inspecionadas e credenciadas pela AAALAC. Os animais foram alojados no alojamento do Centro de Recursos Animais (ARC), mantido pela equipe do laboratório e pela equipe da Divisão de Laboratório e Recursos Animais (DLAR). Os procedimentos para testes comportamentais são métodos padrão na área, aprovados pela American Pain Society e pela International Association for the Study of Pain. O método de eutanásia é consistente com as recomendações do Painel de Eutanásia da Associação Médica Veterinária Americana.

Todos os procedimentos para animais descritos estão em conformidade com o Guia do NIH para o Cuidado e Uso de Animais de Laboratório. Os estudos foram aprovados pelo Comitê de Cuidado e Uso Institucional local (IACUC #23-201364-HSC) do Centro de Ciências da Saúde da Universidade do Novo México. Todos os estudos estão em conformidade com as políticas sob os auspícios de uma Garantia de Conformidade OLAW (A3002-01) sobre o uso de animais em pesquisa, conforme descrito na Parte III. II. Garantias e Certificações....

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H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=IL-1&#946;+promotes+disc+degeneration+and+inflammation+through+direct+injection+of+intervertebral+disc+in+a+rat+lumbar+disc+herniation+model.">IL-1&#946; promotes disc degeneration and inflammation through direct injection of intervertebral disc in a rat lumbar disc herniation model.</a> The Spine Journal. 21 (6), 1031-1041 (2021).</li><li>Millecamps, M., Tajerian, M., Sage, E. H., Stone, L. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioral+signs+of+chronic+back+pain+in+the+SPARC-null+mouse.">Behavioral signs of chronic back pain in the SPARC-null mouse.</a> Spine. 36 (2), 95-102 (2011).</li><li>La Porta, C., Tappe-Theodor, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+impact+of+psychological+and+psychophysical+stress+on+low+back+pain+in+mice.">Differential impact of psychological and psychophysical stress on low back pain in mice.</a> Pain. 161 (7), 1442-1458 (2020).</li><li>Chaplan, S. R., Bach, F. W., Pogrel, J. W., Chung, J. M., Yaksh, T. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+assessment+of+tactile+allodynia+in+the+rat+paw.">Quantitative assessment of tactile allodynia in the rat paw.</a> Journal of Neuroscience Methods. 53 (1), 55-63 (1994).</li><li>Takao, K., Miyakawa, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Light/dark+transition+test+for+mice.">Light/dark transition test for mice.</a> Journal of Visualized Experiments JoVE. (1), e104 (2006).</li><li>Deuis, J. R., Dvorakova, L. S., Vetter, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methods+used+to+evaluate+pain+behaviors+in+rodents.">Methods used to evaluate pain behaviors in rodents.</a> Frontiers in Molecular Neuroscience. 10, 284 (2017).</li><li>David, D. J., 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=Neurogenesis-dependent+and+-independent+effects+of+fluoxetine+in+an+animal+model+of+anxiety/depression.">Neurogenesis-dependent and -independent effects of fluoxetine in an animal model of anxiety/depression.</a> Neuron. 62 (4), 479-493 (2009).</li><li>Yalcin, I., 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=A+time-dependent+history+of+mood+disorders+in+a+murine+model+of+neuropathic+pain.">A time-dependent history of mood disorders in a murine model of neuropathic pain.</a> Biological Psychiatry. 70 (10), 946-953 (2011).</li><li>Madathil, S. 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=Astrocyte-specific+overexpression+of+insulin-like+growth+factor-1+protects+hippocampal+neurons+and+reduces+behavioral+deficits+following+traumatic+brain+injury+in+mice.">Astrocyte-specific overexpression of insulin-like growth factor-1 protects hippocampal neurons and reduces behavioral deficits following traumatic brain injury in mice.</a> PloS One. 8 (6), e67204 (2013).</li><li>Sugimoto, H., Kawakami, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low-cost+protocol+of+footprint+analysis+and+hanging+box+test+for+mice+applied+the+chronic+restraint+stress.">Low-cost protocol of footprint analysis and hanging box test for mice applied the chronic restraint stress.</a> Journal of Visualized Experiments: JoVE. (143), e59027 (2019).</li><li>Hassan, 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=Identifying+chronic+low+back+pain+phenotypic+domains+and+characteristics+accounting+for+individual+variation:+a+systematic+review.">Identifying chronic low back pain phenotypic domains and characteristics accounting for individual variation: a systematic review.</a> Pain. , (2023).</li></ol>

Este modelo de dor lombar crônica é simples de induzir, e a hipersensibilidade estabelecida dentro de 1 semana pode durar até (e possivelmente além) de 8 semanas. Isso permite um estudo preciso do estado de dor crônica, em oposição a outros modelos agudos que duram apenas uma ou duas semanas. Enquanto mostramos o modelo em camundongos, o modelo de CBP induzida por uPA também pode ser estabelecido em ratos2. Uma vantagem do modelo é que o curso temporal prolongado provoca o desenvolvimento...

A dor lombar é uma das causas mais comuns de incapacidade, com 1 em cada 5 pessoas sofrendo em todo o mundo1. Apesar desses esforços, poucos modelos animais confiáveis de dor nas costas são popularmente usados em pesquisas com animais no campo da dor, especialmente em camundongos. Modelos anteriores utilizaram quase que exclusivamente ratos para a indução de dor lombar crônica (CEC), como aquelas induzidas pela injeção do ativador do plasminogênio urinário (uPA) na articulação da facetalombar2,3, injeção de fator de crescimento nervoso (NGF) namusculatura do tronco4, ou iodoacetato monossódico (MIA)5 ou interleucina-1beta6 injeção no disco intravertebral. É claro que os ratos são preferidos para esses modelos principalmente devido ao seu maior tamanho e facilidade de acesso para injeção de agentes inflamatórios.
Para ser claro, existem modelos de dor nas costas em camundongos, como o modelo SPARC-null de degeneração do disco intervertebral em camundongos, usado por muitos anos7, mas estes são mais caros e demorados para serem estabelecidos do que os modelos baseados em injeção. Um estudo recente em camundongos estabeleceu um modelo de dor lombar combinando a injeção de NGF em músculos lombares com estresse de restrição crônica vertical8. No protocolo a seguir, adaptamos o modelo de CBP induzida por uPA de ratos para camundongos2. A hipersensibilidade é estabelecida dentro de 1 semana e persiste até 6-8 semanas. Além disso, estabelecemos que os ratos desenvolvem comportamentos semelhantes aos da ansiedade e da depressão. Dada a prevalência de dor nas costas e o uso mais comum de camundongos em pesquisas moleculares sobre dor, este modelo durável é prontamente estabelecido para uso no desenvolvimento de novas estratégias de tratamento para alívio da dor nas costas.

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			<td>70% ethanol</td>
			<td>Local Source</td>
			<td></td>
			<td></td>
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			<td>BALB/c mice</td>
			<td>Envigo</td>
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			<td>20-25 g</td>
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			<td>Cotton balls</td>
			<td>Fisher Scientific</td>
			<td>19-090-702</td>
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			<td>Cotton-tipped applicators</td>
			<td>Fisher Scientific</td>
			<td>19-062-616</td>
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			<td>Isoflurane inhalant anesthetic</td>
			<td>MedVet</td>
			<td>RXISO-250</td>
			<td></td>
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			<td>Labeling tape</td>
			<td>Fisher Scientific</td>
			<td>NGFP7002</td>
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			<td>Nitrile exam gloves</td>
			<td>Fisher Scientific</td>
			<td></td>
			<td></td>
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			<td>Oxygen tank</td>
			<td>Local Source</td>
			<td></td>
			<td></td>
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			<td>Surgical drape, Steri-Drape Utility Sheet, Absorbent Prevention</td>
			<td>VWR</td>
			<td>76246-788</td>
			<td>cut into 15 x 15 cm pieces</td>
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			<td>Tygon tubing with 3 mm inner diameter</td>
			<td>Grainger</td>
			<td>22XH87</td>
			<td></td>
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			<td>Equipment</td>
			<td></td>
			<td></td>
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			<td>#11 carbon steel scalpel blades</td>
			<td>VWR</td>
			<td>21909-612</td>
			<td></td>
		</tr>
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			<td>Anesthesia induction chamber&#160;</td>
			<td>Summit Medical Equipment Company</td>
			<td>AS-01-0530-LG</td>
			<td></td>
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			<td>Autoclave</td>
			<td>Local Unit</td>
			<td></td>
			<td></td>
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			<td>Biology Dumont #5 forceps</td>
			<td>Fine Science Tools</td>
			<td>11252-30</td>
			<td></td>
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			<td>Glass bead sterilizer Germinator 500</td>
			<td>VWR</td>
			<td>102095-946</td>
			<td></td>
		</tr>
		<tr>
			<td>IITC Life Sciences Series 8 Model PE34 Hot/Cold Plate Analgesia Meter</td>
			<td>IITC</td>
			<td>PE34</td>
			<td></td>
		</tr>
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			<td>Integra Miltex cotton &#38; dressing pliers&#160;</td>
			<td>Safco Dental Supply</td>
			<td>66-317</td>
			<td></td>
		</tr>
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			<td>OPTIKA CL31 double arm LED illuminator&#160;</td>
			<td>New York Microscope Company</td>
			<td>OPCL-31</td>
			<td></td>
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			<td>Plantar Test System with InfraRed Emitter, i. e. Hargreaves Apparatus</td>
			<td>Ugo Basile</td>
			<td>37370-001 and 37370-002</td>
			<td></td>
		</tr>
		<tr>
			<td>Scalpel Handle No. 3</td>
			<td>VWR</td>
			<td>25607-947</td>
			<td></td>
		</tr>
		<tr>
			<td>Small animal heating pad&#160;</td>
			<td>Valley Vet Supply</td>
			<td>47375</td>
			<td></td>
		</tr>
		<tr>
			<td>Student Vannas spring scissors, straight blade&#160;</td>
			<td>Fine Science Tools</td>
			<td>91500-09</td>
			<td></td>
		</tr>
		<tr>
			<td>Table top animal research portable anesthesia workstation &#8220;PAM&#8221;</td>
			<td>Patterson Scientific</td>
			<td>AS-01-0007</td>
			<td></td>
		</tr>
		<tr>
			<td>Von Frey Filaments</td>
			<td>Ugo Basile</td>
			<td>37450-275</td>
			<td></td>
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urokinase-type plasminogen activator-induced mouse back pain model

Um modelo de dor lombar persistente pode ser induzido em camundongos com a metodologia simples aqui descrita. Métodos passo a passo para indução simples e rápida de um modelo de dor persistente nas costas em camundongos são fornecidos aqui usando uma injeção de ativador de plasminogênio do tipo uroquinase (uroquinase), uma serinoprotease presente em humanos e outros animais. A metodologia para indução de dor lombar persistente em camundongos envolve uma simples injeção de uroquinase ao longo da região de inserção ligamentar da coluna lombar. O agente inflamatório uroquinase ativa plasminogênio em plasmina. Normalmente, o modelo pode ser induzido dentro de 10 minutos e a hipersensibilidade persiste por pelo menos 8 semanas.
Hipersensibilidade, distúrbio da marcha e outras medidas padrão semelhantes à ansiedade e depressão podem ser testadas no modelo persistente. A dor nas costas é o tipo de dor mais prevalente. Para melhorar a conscientização sobre a dor nas costas, a Associação Internacional para o Estudo da Dor (IASP) nomeou 2021 o "Ano Global sobre Dor nas Costas" e 2022 o "Ano Global para Traduzir o Conhecimento da Dor para a Prática". Uma limitação do avanço terapêutico da terapêutica da dor é a falta de modelos adequados para testar a dor persistente e crônica. As características deste modelo são adequadas para testar potenciais terapêuticas destinadas à redução da dor nas costas e suas características auxiliares, contribuindo para que o IASP nomeie 2022 como o Ano Global para a Tradução do Conhecimento da Dor para a Prática.

Testes comportamentais relacionados à nocicepção e análise de dados Medidas evocadas A hipersensibilidade no coxim plantar desenvolve-se dentro de um dia após a injeção de uroquinase. Dentro de 1 semana, o limiar de retirada é significativamente reduzido e persiste até a eutanásia; isso é demonstrado até a semana 4 pós-cirúrgica (Figura 4A). A latência de retirada da pata é analisada pelo método de von Frey up-down9</...

Watch this Scientific Journal Video about Urokinase-type Plasminogen Activator-induced Mouse Back Pain Model at JoVE.com

Urokinase-type Plasminogen Activator-induced Mouse Back Pain Model

Métodos para indução simples e rápida de um modelo de dor nas costas em camundongos são fornecidos aqui usando uma injeção intraligamentar de ativador de plasminogênio urinário.

Modelo de dor nas costas de camundongo induzido pelo ativador do plasminogênio do tipo uroquinase

A model of persisting lower back pain can be induced in mice with the simple methodology described herein. Step-by-step methods for simple, rapid ...

Este protocolo descreve um método não invasivo para induzir dor lombar crônica em camundongos por até 10 semanas, que pode ser realizado de forma rápida e confiável com treinamento mínimo. O aspecto mais difícil desta técnica é reconhecer como injetar ligamento se sente versus injetar músculo. Sentir resistência ao contato indica injeção ligamentar.Sem resistência significa que a agulha pode estar no músculo ou na cavidade abdominal. Para começar, pegue uma superfície plana estéril para colocar o mouse. Em seguida, coloque uma estação de recuperação de almofada de aquecimento ao lado da configuração da cirurgia para transferir imediatamente os ratos após a injeção.Em seguida, prepare a uroquinase e uma seringa de Hamilton. Desenhe a solução com antecedência para minimizar o tempo que o rato passa sob anestesia. Após anestesiar o camundongo, utilizar dois dedos para localizar os segmentos da coluna lombar em L2 e L3 abaixo da caixa torácica e verificar o local da injeção.Coloque a ponta da seringa de Hamilton ao lado da coluna. Posicione a seringa em um ângulo de aproximadamente 45 graus no ligamento imediatamente adjacente ao osso. Insira a ponta da agulha suavemente, mas com firmeza, no ligamento e injete lentamente até que todos os cinco microlitros tenham sido injetados.Retire a agulha suave e lentamente. Em seguida, coloque o mouse na estação de recuperação de calor até que ele acorde e se torne móvel. Verifique os ratos por uma hora após a cirurgia para garantir que toda a função motora normal continue.Após a cirurgia, verifique o peso e o local de injeção dos ratos diariamente por uma semana para evitar qualquer infecção ou complicações. Antes de testar, mova cada animal para um cubículo transparente separado na mesa de teste com uma parte superior da tela. Em seguida, estimule o coxim pé com o filamento de Von Frey 3,61 que provoca quatro gramas de força.A retirada dos pés de três a cinco estímulos é considerada uma resposta positiva. Agora, aplique o próximo filamento mais fraco da série até que o animal pare de responder ao estímulo mecânico. Use o filamento superior até que uma resposta seja obtida e, em seguida, volte para o filamento inferior.Usando um algoritmo de ajuste de curva, calcule o limiar de retirada mecânica, que é a quantidade mínima de força necessária para provocar uma resposta em 50% do tempo. Para realizar o Teste de Hargreaves, coloque os ratos em cubículos em uma superfície de vidro aquecida por baixo por um emissor infravermelho. Meça o tempo desde a aplicação do estímulo de luz infravermelha na pata traseira do rato até a retirada como latência do pé.Para o Teste da Placa Fria, coloque os ratos no aparelho de placa fria resfriado a menos nove graus Celsius. Registre o tempo que o mouse leva para levantar o pé após ser colocado no aparelho como a latência para retirar o pé. Para realizar o Teste de Ansiedade, posicione cada animal na caixa de teste de preferência de local com uma passagem entre duas câmaras.Uma câmara do aparelho deve estar iluminada com clareza, enquanto o lado oposto deve permanecer escuro. Usando um computador, monitore os tempos de ocupação e transições claros e escuros do animal durante um teste de 10 minutos. Em seguida, coloque os roedores modelo ou animais ingênuos no labirinto zero, ou use o teste de preferência de lugar claro ou escuro de duas câmaras.Avalie o tempo gasto em áreas fechadas e abertas do labirinto usando um cronômetro. Para o Sucarose Splash Depression Test, borrife uma solução de sacarose a 10 a 30% no código dorsal e pontue a frequência, duração e latência da tosa por 10 minutos. Para realizar novos testes com objetos, aclimate camundongos individualmente a uma gaiola de plástico transparente com uma tampa aberta por uma hora.Adicione duas mini figuras de brinquedo idênticas em cantos opostos da gaiola por cinco minutos. Aclimatar os animais no dia do teste por uma hora e colocar as duas mini figuras idênticas nas mesmas posições da gaiola por cinco minutos antes de devolvê-los à gaiola de origem. Em seguida, substitua uma das figuras originais por um objeto novo distintamente diferente.Após quatro horas, devolva os ratos à gaiola de teste e registre o tempo gasto explorando os objetos. Para avaliação da função motora, construa um túnel a partir de um tubo de papel toalha cortado longitudinalmente em uma borda. Espalhe o túnel em um pedaço limpo de papel de impressora.Segure os ratos suavemente até que estejam calmos. Aplique tinta indiana não tóxica nas patas de um rato, colocando-as em um poço de tinta, bloco de carimbo ou usando um cotonete. Solte os ratos na entrada do túnel.Permita que eles corram pelo túnel e os capturem no final. Marcar impressões de patas com base no comprimento da passada, largura da passada e espalhamento dos dedos. Ensaios de hipersensibilidade mecânica e térmica demonstraram que os camundongos com dor lombar crônica tiveram sensibilidade mecânica, ao calor e ao frio significativamente aumentada em comparação com os controles virgens.A análise de ansiedade mostrou que o tempo total gasto na câmara de luz da caixa clara e escura e o número de eventos de criação foram significativamente menores em camundongos com dor crônica nas costas, indicando ansiedade. Durante o Sucarose Splash Test, camundongos com dor lombar crônica apresentaram menor tempo de tosa e o número de tosas. No entanto, o tempo para o início da tosa aumentou significativamente.O comprimento da passada entre camundongos com dor lombar crônica e camundongos virgens foi significativamente diferente. A coisa mais importante a lembrar ao tentar este procedimento é que você está visando os ligamentos ao redor da coluna, não o músculo. O modelo de dor lombar crônica fornece uma ferramenta confiável para avaliar uma variedade de novas pesquisas, farmacológicas e outras potenciais terapêuticas.

urokinase-type-plasminogen-activator-induced-mouse-back-pain-model

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Behavior

Assessing Functional Performance in the Mdx Mouse Model

Duchenne muscular dystrophy (DMD) is a severe and progressive muscle wasting disorder for which no cure is available. Nevertheless, several potential pharmaceutical compounds and gene therapy approaches have progressed into clinical trials. With improvement in muscle function being the most important end point in these trials, a lot of emphasis has been placed on setting up reliable, reproducible, and easy to perform functional tests to pre clinically assess muscle function, strength, condition, and coordination in the mdx mouse model for DMD. Both invasive and noninvasive tests are available. Tests that do not exacerbate the disease can be used to determine the natural history of the disease and the effects of therapeutic interventions (e.g. forelimb grip strength test, two different hanging tests using either a wire or a grid and rotarod running). Alternatively, forced treadmill running can be used to enhance disease progression and/or assess protective effects of therapeutic interventions on disease pathology. We here describe how to perform these most commonly used functional tests in a reliable and reproducible manner. Using these protocols based on standard operating procedures enables comparison of data between different laboratories.

Assessing Functional Performance in the Mdx Mouse Model

The primary outcome measure in clinical trials for neuromuscular disorders is generally improved muscle function. Therefore, assessing the effect of potential therapeutic compounds on muscle performance pre clinically in mouse models is of great importance. We here describe several functional tests to address this.

Avaliação do Desempenho Funcional no<em&gt; Mdx</em&gt; Mouse Modelo

Duchenne muscular dystrophy (DMD) is a severe and progressive muscle wasting disorder for which no cure is available. Nevertheless, several potential ...

Comportamento

Determining Pain Detection and Tolerance Thresholds Using an Integrated, Multi-Modal Pain Task Battery

Human pain models are useful in the assessing the analgesic effect of drugs, providing information about a drug&#39;s pharmacology and identify potentially suitable therapeutic populations. The need to use a comprehensive battery of pain models is highlighted by studies whereby only a single pain model, thought to relate to the clinical situation, demonstrates lack of efficacy. No single experimental model can mimic the complex nature of clinical pain. The integrated, multi-modal pain task&#160;battery presented here encompasses the electrical stimulation task, pressure stimulation task, cold pressor task, the UVB inflammatory model which includes a thermal task and a paradigm for inhibitory conditioned pain modulation. These human pain models have been tested for predicative validity and reliability both in their own right and in combination, and can be used repeatedly, quickly, in short succession, with minimum burden for the subject and with a modest quantity of equipment. This allows a drug to be fully characterized and profiled for analgesic effect which is especially useful for drugs with a novel or untested mechanism of action.

Human pain models are valuable tools used to assess the analgesic potential of novel compounds and predict their clinical efficacy, especially when used in an integrated manner. Although implementation of these models is complex, with proper execution, the pain models described in this protocol can provide predictive and reliable results.

Determinando Detecção Dor e limiares de tolerância Usando uma Integrado, Multi-Modal Dor Task Bateria

Human pain models are useful in the assessing the analgesic effect of drugs, providing information about a drug&#39;s pharmacology and identify ...

Treating Low Back Pain in Failed Back Surgery Patients with Multicolumn-lead Spinal Cord Stimulation

Failed back surgery syndrome (FBSS) refers to persistent, chronic pain following spinal surgery. Spinal cord stimulation with dorsal epidural leads can be used to treat back and leg pain in FBSS patients. This paper presents a detailed protocol for using spinal cord stimulation with surgical leads in FBSS patients. In our department, with the patient under general anesthesia, we place the lead in the epidural space by means of a small laminectomy at the 10th thoracic level. Placement of the lead is followed by a 1 month trial period with an externalized lead. If pain relief is greater than 50% at the end of this 1 month stimulation trial (required by Belgian reimbursement criteria), an internal pulse generator is then placed under the skin and connected to the lead in a second surgical procedure. We have demonstrated that using this technique in rigorously selected FBSS patients can significantly improve back pain, leg pain, patient activity, and quality of life for a sustained period of time.

This paper presents a method that uses spinal cord stimulation with a multicolumn lead to treat neuropathic low back pain in failed back surgery patients.

Tratamento de dor lombar em pacientes de cirurgia nas costas falha com estimulação medular Multicolumn-chumbo

Failed back surgery syndrome (FBSS) refers to persistent, chronic pain following spinal surgery. Spinal cord stimulation with dorsal epidural leads can be ...

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 ...

Chronic Post-Ischemia Pain Model for Complex Regional Pain Syndrome Type-I in Rats

Complex regional pain syndrome type-I (CRPS-I) is a neurological disease that causes severe pain among patients and remains an unresolved medical condition. However, the underlying mechanisms of CRPS-I have yet to be revealed. It is known that ischemia/reperfusion is one of the leading factors that causes CRPS-I. By means of prolonged ischemia and reperfusion of the hind limb, the rat chronic post-ischemia pain (CPIP) model has been established to mimic CRPS-I. The CPIP model has become a well-recognized animal model for studying the mechanisms of CRPS-I. This protocol describes the detailed procedures involved in the establishment of the rat model of CPIP, including anesthesia, followed by ischemia/reperfusion of the hind limb. Characteristics of the rat CPIP model are further evaluated by measuring the mechanical and thermal hypersensitivities of the hind limb as well as the nocifensive responses to acute capsaicin injection. The rat CPIP model exhibits several CRPS-I-like manifestations, including hind limb edema and hyperemia in the early stage after establishment, persistent thermal and mechanical hypersensitivities, and increased nocifensive responses to acute capsaicin injection. These characteristics render it a suitable animal model for further investigation of the mechanisms involved in CRPS-I.

Provided here is a protocol that details steps to establish an animal model of chronic post-ischemia pain (CPIP). This is a well-recognized model mimicking human complex regional pain syndrome type-I. Mechanical and thermal hypersensitivities are further evaluated, as well as capsaicin-induced nocifensive behaviors observed in the CPIP rat model.

Modelo crônico da dor da Borne-Isquemia para a síndrome regional complexa da dor tipo-I nos ratos

Complex regional pain syndrome type-I (CRPS-I) is a neurological disease that causes severe pain among patients and remains an unresolved medical ...

Investigating Pain-Related Avoidance Behavior using a Robotic Arm-Reaching Paradigm

Avoidance behavior is a key contributor to the transition from acute pain to chronic pain disability. Yet, there has been a lack of ecologically valid paradigms to experimentally investigate pain-related avoidance. To fill this gap, we developed a paradigm (the robotic arm-reaching paradigm) to investigate the mechanisms underlying the development of pain-related avoidance behavior. Existing avoidance paradigms (mostly in the context of anxiety research) have often operationalized avoidance as an experimenter-instructed, low-cost response, superimposed on stimuli associated with threat during a Pavlovian fear conditioning procedure. In contrast, the current method offers increased ecological validity in terms of instrumental learning (acquisition) of avoidance, and by adding a cost to the avoidance response. In the paradigm, participants perform arm-reaching movements from a starting point to a target using a robotic arm, and freely choose between three different movement trajectories to do so. The movement trajectories differ in probability of being paired with a painful electrocutaneous stimulus, and in required effort in terms of deviation and resistance. Specifically, the painful stimulus can be (partly) avoided at the cost of performing movements requiring increased effort. Avoidance behavior is operationalized as the maximal deviation from the shortest trajectory on each trial. In addition to explaining how the new paradigm can help understand the acquisition of avoidance, we describe adaptations of the robotic arm-reaching paradigm for (1) examining the spread of avoidance to other stimuli (generalization), (2) modeling clinical treatment in the lab (extinction of avoidance using response prevention), as well as (3) modeling relapse, and return of avoidance following extinction (spontaneous recovery). Given the increased ecological validity, and numerous possibilities for extensions and/or adaptations, the robotic arm-reaching paradigm offers a promising tool to facilitate the investigation of avoidance behavior and to further our understanding of its underlying processes.

Avoidance is central to chronic pain disability, yet adequate paradigms for examining pain-related avoidance are lacking. Therefore, we developed a paradigm that allows investigating how pain-related avoidance behavior is learned (acquisition), spreads to other stimuli (generalization), can be mitigated (extinction), and how it may subsequently re-emerge (spontaneous recovery).

Investigando o comportamento de prevenção relacionado à dor usando um paradigma robótico de alcance de braço

Avoidance behavior is a key contributor to the transition from acute pain to chronic pain disability. Yet, there has been a lack of ecologically valid ...

Back Mechanical Sensitivity Assessment in the Rat for Mechanistic Investigation of Chronic Back Pain

Low back pain is the leading cause of disability worldwide, with dramatic personal, economic, and social consequences. To develop novel therapeutics, animal models are needed to examine the mechanisms and effectiveness of novel therapies from a translational perspective. Several rodent models of back pain are used in current investigations. Surprisingly, however, no standardized behavioral test was validated to assess mechanical sensitivity in back pain models. This is critical to confirm that animals with presumed back pain present local hypersensitivity to nociceptive stimuli, and to monitor sensitivity during interventions designed to relieve back pain. The objective of this study is to lay down a simple and accessible test to assess mechanical sensitivity in the back of rats. A test cage was fabricated specifically for this method; length x width x height: 50 x 20 x 7 cm, having a stainless-steel mesh on the top. This test cage allows the application of mechanical stimuli to the back. To perform the test, the back of the animal is shaved in the region of interest, and the test area is marked to repeat the test on different days, as needed. The mechanical threshold is determined with Von Frey filaments applied to the paraspinal muscles, utilizing the up-down method described previously. The positive responses include (1) muscle twitching, (2) arching (back extension), (3) rotation of the neck (4) scratching or licking the back, and (5) escaping. This behavioral test (Back Mechanical Sensitivity (BMS) test) is useful for mechanistic research with rodent models of back pain for the development of therapeutic interventions for the prevention and management of back pain.

To develop novel therapeutic interventions for the prevention and management of back pain, animal models are required to examine the mechanisms and effectiveness of these therapies from a translational perspective. The present protocol describes the BMS test, a standardized method to assess back mechanical sensitivity in the rat.

Avaliação da Sensibilidade Mecânica das Costas no Rato para Investigação Mecanicista da Dor Lombar Crônica

Low back pain is the leading cause of disability worldwide, with dramatic personal, economic, and social consequences. To develop novel therapeutics, ...

Elevated Plus Maze Test in an Angelman Syndrome Mouse Model

To begin, place the plus shaped maze on the testing platform just below the camera. Using the potentiometer on the wall, adjust the light intensity to 70 luxe at its center with the help of a luxometer with its sensor placed at the center of the maze during the adjustment. Open the software by double clicking on the viewer software icon and load the configuration for Elevated Plus Maze or EPM testing by clicking on the icon on the upper left side of the configuration tab.Enter the animal information into the corresponding fields of the experiment tab including animal id, genotype, gender, and experiment information. Verify that the zone's position, open arms, and closed arms are correctly configured. Using a visual control and computer mouse, ensure that the virtual outline zones match the corresponding EPM zones.Place the mouse cursor on the arrow icon on the upper left side of the acquisition tab. Remove the animal from the home cage and place it gently in the center of the EPM. Start the experiment by left clicking on the computer mouse.After five minutes, save the recorded data by clicking okay. Name the file and click save. Export the results to a csv file for offline analysis by clicking on the icon on the left vertical panel of the data analysis tab.In the EPM test, none of the parameters related to anxiety-like behavior were altered in maternal heterozygous Ube3A mutants.

Teste de labirinto em cruz elevado em um modelo de camundongo com síndrome de Angelman

Open Field Test in an Angelman Syndrome Mouse Model

Place the four open field, or OF, test boxes on the testing platform below the camera. Using the potentiometer on the wall, adjust the light intensity to 200 lux at the center of each OF test with the help of a luxometer with its sensor placed at the center of each box during the adjustment. Open the software by double clicking on the viewer software icon and load the configuration for EF testing by clicking on the icon on the upper left side of the configuration tab.Enter the animal information into the corresponding fields of the experiment tab. Verify that the zone's position matches the OF test boxes and adjust them if needed. Using a visual control and computer mouse, ensure that the virtual outline center and periphery zones match the corresponding OF test zones.Place the mouse cursor on the arrow icon on the upper left side of the acquisition tab. Remove four animals from the home cage and place them in the corner of each test box. Stop the experiment by left clicking on the computer mouse.In the OF test, the maternal heterozygous Ube3a mutant animals were significantly hypoactive as reflected by a shorter traversed distance, lower average speed, and longer resting time. However, none of the parameters related to anxiety-like behavior were altered in Ube3a mutants.

Teste de Campo Aberto em Modelo de Camundongo com Síndrome de Angelman

Tail Suspension Test in an Angelman Syndrome Mouse Model

Connect the tail suspension cage to the computer using a USB cable. Insert the USB dongle into the computer and start the software by double clicking on the BioTSD software icon. In the settings tab on the global, ensure the acquisition duration is set to 360 seconds.In the experiment tab, select the new list of subjects and create a new experiment file and a new list of tested subjects by following the instructions in the opened tab. Prepare the animals for the test by wrapping single-sided adhesive tape around three-fourths of the animal's tail starting from the base. Start the run by clicking start run then continue in the acquisition tab.Immediately after hanging the animal on the hook, click the start icon under the visualized position to acquire data. After testing all the animals, in the analysis tab, select the last four minutes of the acquisition for analysis. Select all valid runs in the analysis period and click analyze selected subjects.Choose the desired data format and click export selected data to export the collected data. In the tail suspension test, Ube3a mutant animals were immobile for significantly longer than their control littermates, indicating their depression-like behavior.