The authors acknowledge the funding support from the Ministry of Education, Singapore, grant number MOE2010-IF-1-025.

Todos os experimentos com animais foram aprovados pelo comitê de cuidados com os animais e utilização da Faculdade de Ciências Aplicadas, Temasek Polytechnic. 1. Preparação de DMN <ol><li> Pipetar 200 l de DMN (1 g / ml de solução) e adicionar 19,8 mL de PBS para preparar a solução DMN 10 mg / ml para a injecção. Nota: DMN é cancerígeno. Use um exaustor para preparar o DMN e executar as injecções de animais. </li></ol> 2. injecção intraperitoneal de DMN <ol><li> Use ratos Wistar machos com um peso médio de 150-200 g. Aclimatar os ratos de 4 - 7 dias antes do início da experiência. </li><li> Manter ratos à temperatura ambiente de 22 ± 1 ° C, com 12 luz hr e 12 hr ciclos escuros. Forneça ração e água ad libitum. </li><li> Medida de comida e água ingestão diária. Meça corpo semanal de peso. </li><li> Calcular a quantidade de DMN para cada rato com base numa dose de 10 mg / kg de peso corporal. Use uma seringa de 1 ml com uma agulha de calibre 25 triar o volume calculado de solução DMN para dentro da seringa. </li><li> Contenha o rato para injecção intraperitoneal 21. </li><li> Com o rato, devidamente presas, introduzir a agulha no quadrante inferior direito do abdômen, chamar de volta o êmbolo da seringa (nada deve ser aspirado) para verificar o posicionamento correto da agulha dentro do espaço abdominal e injecte lentamente solução DMN. </li><li> Quando foi administrada a dose de DMN, retirar lentamente a agulha e eliminar para o recipiente de agulhas. </li><li> As injecções intraperitoneais de DMN durante 3 dias consecutivos por semana, durante 4 semanas. Administrar as injecções ao mesmo tempo em cada dia. Re-calcular a dosagem baseada no peso corporal, no início de cada semana de injecções. </li><li> Recolha de sangue da veia da cauda semanal para medir parâmetros bioquímicos: alanina aminotransferase (ALT) e aspartato aminotransferase (AST) 22. </li><li> ALT sérica medida e AST usando um Vet comercialTeste Chemistry Analyzer. </li></ol> 3. Exame Bruto e Colheita de fígado <ol><li> Eutanásia os ratos por injecção intraperitoneal de pentobarbital a uma dose de 100 mg / kg de peso corporal. Certifique-se de morte, verificando a ausência de batimentos cardíacos. </li><li> Prepare-se para o post mortem e avaliar a condição do animal, como descrito por ratos mortos Parkinson et al. 23 Lugar na placa de dissecação em decúbito dorsal com o abdômen virado para cima. </li><li> Desinfectar e umedecer a pele com etanol 70%. </li><li> Com uma tesoura, uma incisão na pele de todo o comprimento do ventrum do ânus para o queixo, e reflectem a pele. Com uma tesoura, uma incisão na parede abdominal do ânus para a cartilagem xifóide, para expor as vísceras abdominais. </li><li> Examinar os órgãos abdominais in situ para verificar se há qualquer anormalidade. Nota quaisquer alterações na cor, tamanho, localização de órgãos e a presença de líquido no interior da cavidade peritoneal. Examinara consistência dos órgãos e observe a presença de quaisquer odores. </li><li> Com uma tesoura e uma pinça, dissecar todo o livre fígado de seus ligamentos e anexos. <ol><li> Comece no hilo, onde ele está ligado ao diafragma e trabalhar para libertar todos os lobos do fígado de anexos. Corte cuidadosamente todos os ligamentos e vasos sanguíneos. </li></ol></li><li> Transferir o fígado para uma placa de petri e pesa o fígado. </li><li> Utilizando um bisturi, cortar 2 - 5 milímetros de espessura de lobos hepáticos. Para consistência, sempre tomar amostras de um mesmo lobo hepático. Aqui uma cunha de cerca de 5 mm de diâmetro de espessura, a partir do lóbulo lateral direito 24 cerca de 1 cm do bordo do lugar lobe.Immediately em formalina a 10% tamponada para fixação. Assegurar que o tecido para o volume de formalina é 01:10 ou mais. </li><li> Colheita e congelar imediatamente porções (usando nitrogênio líquido) dos lobos do fígado neste momento, se necessário para outros estudos. Tal como para (3,8), da amostra a partir do mesmo lóbulo do fígado para a consistência. </li></ol><ol><li> Fixar as amostras de fígado em 10% de formalina tamponada para um mínimo de 24 horas. </li><li> Após a fixação, cortar o fígado, coloque em cassetes e carregá-los no cesto do processador de tecido automático. </li><li> Colocar o cesto com cassetes para a primeira estação, que contém 10% de formalina tamponada. Garantir as cassetes são totalmente submerso. Eles podem permanecer nesta câmara para até 12 horas até que o ciclo começa. </li><li> Programar o processador de tecidos para rodar as cassetes durante 1 h cada, através de estações sucessivas contendo as seguintes soluções: etanol em concentrações de 50%, 70%, 90%, 100% (2 estações), o xileno (2 estações) e parafina líquida ( 2 estações). </li><li> Transferir as amostras de fígado para o banho de cera da estação de embebimento. Assegure-se que a incorporação da máquina é ligada, pelo menos, uma hora mais cedo. </li><li> Usando fórceps pré-aquecido (65 ° C), remover cada cassete da Wbanho de machado e lugar sobre a placa quente (65 ° C) da máquina incorporação. Dispensar quantidade suficiente de parafina líquida para o molde da base de aço inoxidável (pré-aquecido a 65 ° C) até metade cheio. Transferir a secção de fígado a partir da cassete para dentro do molde. Garantir que o espécime é colocado com a superfície de corte (a serem examinadas microscopicamente) plana sobre o fundo do molde. </li><li> Encha o molde completamente com parafina líquida, montar a cassete vazia em cima e coloque o molde na placa de 4 ° C da máquina incorporação esfriar por pelo menos 30 min. </li><li> Verifique se a cera esfriou e solidificou, e remova o bloco de parafina a partir do molde. O bloco deve sair facilmente e não furar ou crack. Se isso acontecer, derreter o bloco e repita esta etapa. O bloco de parafina pode ser seccionado, uma vez que se solidifica. Os blocos podem ser armazenadas à temperatura ambiente durante muitos anos. </li><li> Coloque o bloco de parafina para o micrótomo e seção de 10 m de espessura, até a camada de ceraé removido suficientemente para o tecido do fígado incorporado para ser visível. </li><li> Alterar a configuração do micrótomo para cortar a 5 mm de espessura. Utilizando uma pinça, pegar uma seção bem cortadas, segurando-o na borda e flutuar atentamente a secção no banho de água a uma temperatura de 40 ° C. </li><li> Suavemente colocar uma lâmina de vidro limpa sob o ponto flutuante e levantá-la sobre a superfície da lâmina de vidro. Colocar a lâmina sobre uma lâmina quente a 37 ° C durante a noite. </li></ol> 5. tricromo Masson <ol><li> Antes de aplicar as manchas, tratar as lâminas para remover a cera e re-hidratar os tecidos como se segue: <ol><li> Mergulhe as seções em xileno durante 5 min. Repetir 2x. </li><li> Mergulhe as secções em etanol 100% por 3 min. Repetir 1x. </li><li> Mergulhar as secções durante 1 min cada, nas seguintes soluções de etanol: 90%, 80% e 70%. </li></ol></li><li> Lavar a lâmina em água corrente para remover qualquer etanol existente no slide. </li><li> Imergir as lâminas de ferro em hematoxilina durante 10 minutos para corar o núcleo. </li><li> Lavar as lâminas com água para remover o excesso de corante da corrediça. </li><li> Imergir as lâminas em Biebrich Scarlet-ácido Fuchsin por 2 min para manchar o citoplasma. </li><li> Lavar as lâminas com água. </li><li> Colocar as lâminas em solução de ácido fosfotúngstico / fosfomolíbdico por 10 min para promover a absorção de Anilina azul. Alterar a solução de ácido fosfotúngstico / fosfomolíbdico após 2 rodadas de uso. </li><li> Colocar as lâminas em solução de azul de anilina por 10 min para corar as fibras de colágeno. </li><li> Lavar o excesso de corante com água e colocar as lâminas em solução de ácido acético a 1% durante 1 min para permitir a diferenciação para ter lugar para tornar a cor da lâmina mais delicada e transparente. </li><li> Lavar as lâminas com água e proceder a desidratar as secções de tecido. Os passos de desidratação são como se segue: </li><li> Mergulhar as lâminas sucessivamente durante 10 seg de cada vez, na seguinte concentrations de etanol: 70%, 80%, 95% e 100%. </li><li> Mergulhar as lâminas durante 30 segundos em 100% de etanol. Repetir 1x. </li><li> Lavar as lâminas através de 3 estações de xileno durante 5 minutos cada para remover o etanol. </li><li> Montar uma lamela de vidro para a amostra com meios de montagem (por exemplo, DPX montagem) e deixar secar. Nota: DPX é uma resina sintética que seca rapidamente, preserva mancha e protege a secção de tecido. </li></ol> 6. fibrose Scoring em secções Tricoma manchados de Masson de fígado <ol><li> Possui um patologista avaliar a gravidade da fibrose de acordo com a fibrose marcar 25. Seria melhor se o marcador fibrose é feito por dois ou três patologistas de forma independente de modo cego. Em tal cenário, obter uma pontuação final após discussão e revisão do grupo para resolver quaisquer diferenças na pontuação. </li></ol><table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody><tr><td> Ponto </td><td> Descrição </td></tr><tr><td> 0 </td><td> Sem fibrose </td></tr><tr><td> 1 </td><td> expansão fibrosa de algumas áreas do portal, com ou sem curto septos fibrosos </td></tr><tr><td> 2 </td><td> expansão fibrosa da maior parte das áreas de portal, com ou sem curto septos fibrosos </td></tr><tr><td> 3 </td><td> expansão fibrosa da maior parte das áreas de portal, portal ocasional ao portal (PP) colmatar </td></tr><tr><td> 4 </td><td> expansão fibrosa de áreas de portal com marcada ponte (portal para o portal (PP), bem como portal para central (PC) </td></tr><tr><td> 5 </td><td> Marcado ponte (PP e / ou PC) com nódulos ocasionais (cirrose incompleta) </td></tr><tr><td> 6 </td><td> Cirrose, provável ou definitiva </td></tr></tbody></table> Tabela 1: Fibrose escore utilizado para leitura das seções Tricoma manchado fígado do Masson 25.

<ol>
	<li>Magee, P. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toxic+liver+injury;+the+metabolism+of+dimethylnitrosamine.">Toxic liver injury; the metabolism of dimethylnitrosamine.</a> Biochem J. 64 (4), 676-682 (1956).</li><li>Pritchard, D. J., Butler, W. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Apoptosis-the+mechanism+of+cell+death+in+dimethylnitrosamine-induced+hepatotoxicity.">Apoptosis-the mechanism of cell death in dimethylnitrosamine-induced hepatotoxicity.</a> J Pathol. 158 (3), 253-260 (1989).</li><li>Madden, J. W., Gertman, P. M., Peacock, E. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dimethylnitrosamine-induced+hepatic+cirrhosis:+a+new+canine+model+of+an+ancient+human+disease.">Dimethylnitrosamine-induced hepatic cirrhosis: a new canine model of an ancient human disease.</a> Surgery. 68 (1), 260-267 (1970).</li><li>Jenkins, S. A., Grandison, A., Baxter, J. N., Day, D. W., Taylor, I., Shields, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+dimethylnitrosamine-induced+model+of+cirrhosis+and+portal+hypertension+in+the+rat.">A dimethylnitrosamine-induced model of cirrhosis and portal hypertension in the rat.</a> J Hepatol. 1 (5), 489-499 (1985).</li><li>J&#233;z&#233;quel, A. M., Mancini, R., Rinaldesi, M. L., Macarri, G., Venturini, C., Orlandi, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+morphological+study+of+the+early+stages+of+hepatic+fibrosis+induced+by+low+doses+of+dimethylnitrosamine+in+the+rat.">A morphological study of the early stages of hepatic fibrosis induced by low doses of dimethylnitrosamine in the rat.</a> J Hepatol. 5 (2), 174-181 (1987).</li><li>George, J., Chandrakasan, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+characteristics+of+dimethylnitrosamine+induced+fibrotic+liver+collagen.">Molecular characteristics of dimethylnitrosamine induced fibrotic liver collagen.</a> Biochim Biophys Acta, Protein Struct Mol Enzymol. 1292 (2), 215-222 (1996).</li><li>Winwood, P. J., Arthur, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kupffer+cells:+their+activation+and+role+in+animal+models+of+liver+injury+and+human+liver+disease.">Kupffer cells: their activation and role in animal models of liver injury and human liver disease.</a> Semin Liver Dis. 13 (1), 50-59 (1993).</li><li>Nakamura, T., Sakata, R., Ueno, T., Sata, M., Ueno, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inhibition+of+transforming+growth+factor&#946;+prevents+progression+of+liver+fibrosis+and+enhances+hepatocyte+regeneration+in+dimethylnitrosamine-treated+rats.">Inhibition of transforming growth factor&#946; prevents progression of liver fibrosis and enhances hepatocyte regeneration in dimethylnitrosamine-treated rats.</a> Hepatology. 32 (2), 247-255 (2000).</li><li>Shek, F. W., Benyon, R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+can+transforming+growth+factor+beta+be+targeted+usefully+to+combat+liver+fibrosis?.">How can transforming growth factor beta be targeted usefully to combat liver fibrosis?.</a> Eur J Gastroenterol Hepatol. 16 (2), 123-126 (2004).</li><li>Wang, J. H., Shin, J. W., Son, J. Y., Cho, J. H., Son, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antifibrotic+effects+of+CGX,+a+traditional+herbal+formula,+and+its+mechanisms+in+rats.">Antifibrotic effects of CGX, a traditional herbal formula, and its mechanisms in rats.</a> J Ethnopharmacol. 127 (2), 534-542 (2010).</li><li>Su, L. J., Hsu, S. L., Yang, J. S., Tseng, H. H., Huang, S. F., Huang, C. Y. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+gene+expression+profiling+of+dimethylnitrosamine-induced+liver+fibrosis:+from+pathological+and+biochemical+data+to+microarray+analysis.">Global gene expression profiling of dimethylnitrosamine-induced liver fibrosis: from pathological and biochemical data to microarray analysis.</a> Gene Expr. 13 (2), 107-132 (2006).</li><li>M&#252;ller, A., Machnik, F., Zimmermann, T., Schubert, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thioacetamide-induced+cirrhosis-like+liver+lesions+in+rats+usefulness+and+reliability+of+this+animal+model.">Thioacetamide-induced cirrhosis-like liver lesions in rats usefulness and reliability of this animal model.</a> Exp Pathol. 34 (4), 229-236 (1988).</li><li>Martinez-Hernandez, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+hepatic+extracellular+matrix.+II.+Electron+immunohistochemical+studies+in+rats+with+CCl4-induced+cirrhosis.">The hepatic extracellular matrix. II. Electron immunohistochemical studies in rats with CCl4-induced cirrhosis.</a> Lab Invest. 53 (2), 166-186 (1985).</li><li>Pritchard, M. T., Apte, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Models+to+Study+Liver+Regeneration.">Models to Study Liver Regeneration.</a> Liver Regeneration. , 15-40 (2015).</li><li>Kountouras, J., Billing, B. H., Scheuer, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prolonged+bile+duct+obstruction:+a+new+experimental+model+for+cirrhosis+in+the+rat.">Prolonged bile duct obstruction: a new experimental model for cirrhosis in the rat.</a> Br J Exp Pathol. 65 (3), 305-311 (1984).</li><li>Marques, T. G., Chaib, E., 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=Review+of+experimental+models+for+inducing+hepatic+cirrhosis+by+bile+duct+ligation+and+carbon+tetrachloride+injection.">Review of experimental models for inducing hepatic cirrhosis by bile duct ligation and carbon tetrachloride injection.</a> Acta Cir Bras. 27 (8), 589-594 (2012).</li><li>Wasser, S., Tan, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+models+of+hepatic+fibrosis+in+the+rat.">Experimental models of hepatic fibrosis in the rat.</a> Ann Acad Med Singapore. 28 (1), 109-111 (1999).</li><li>George, J., Chandrakasan, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemical+abnormalities+during+the+progression+of+hepatic+fibrosis+induced+by+dimethylnitrosamine.">Biochemical abnormalities during the progression of hepatic fibrosis induced by dimethylnitrosamine.</a> Clin Biochem. 33 (7), 563-570 (2000).</li><li>Shimizu, I., Ma, Y. 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=Effects+of+Sho-saiko-to,+a+Japanese+herbal+medicine,+on+hepatic+fibrosis+in+rats.">Effects of Sho-saiko-to, a Japanese herbal medicine, on hepatic fibrosis in rats.</a> Hepatology. 29 (1), 149-160 (1999).</li><li>Wang, Y., Gao, J., Zhang, D., Zhang, J., Ma, J., Jiang, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+insights+into+the+antifibrotic+effects+of+sorafenib+on+hepatic+stellate+cells+and+liver+fibrosis.">New insights into the antifibrotic effects of sorafenib on hepatic stellate cells and liver fibrosis.</a> J Hepatol. 53 (1), 132-144 (2010).</li><li>Machholz, E., Mulder, G., Ruiz, C., Corning, B. F., Pritchett-Corning, K. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Manual+Restraint+and+Common+Compound+Administration+Routes+in+Mice+and+Rats.">Manual Restraint and Common Compound Administration Routes in Mice and Rats.</a> J Vis Exp. (67), (2012).</li><li>Lee, G., Goosens, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sampling+Blood+from+the+Lateral+Tail+Vein+of+the+Rat.">Sampling Blood from the Lateral Tail Vein of the Rat.</a> J Vis Exp. (99), (2015).</li><li>Parkinson, C. M., O'Brien, A., Albers, T. M., Simon, M. A., Clifford, C. B., Pritchett-Corning, K. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diagnostic+Necropsy+and+Selected+Tissue+and+Sample+Collection+in+Rats+and+Mice.">Diagnostic Necropsy and Selected Tissue and Sample Collection in Rats and Mice.</a> J Vis Exp. (54), (2011).</li><li>Ruehl-Fehlert, C., Kittel, B., 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=Revised+guides+for+organ+sampling+and+trimming+in+rats+and+mice--part+1.">Revised guides for organ sampling and trimming in rats and mice--part 1.</a> Exp Toxicol Pathol. 55 (2-3), 91-106 (2003).</li><li>Ishak, K., Baptista, A., 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=Histological+grading+and+staging+of+chronic+hepatitis.">Histological grading and staging of chronic hepatitis.</a> J Hepatol. 22 (6), 696-699 (1995).</li><li>Sant'Anna, L. B., Sant'Anna, N., Parolini, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+computer+assisted+image+analysis+for+identifying+and+quantifying+liver+fibrosis+in+a+experimental+model.">Application of computer assisted image analysis for identifying and quantifying liver fibrosis in a experimental model.</a> J Comput Interdiscip Sci. 2 (2), 139-148 (2011).</li></ol>

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Nós descrevemos um método para fazer um modelo animal de fibrose hepática e para avaliar a gravidade da fibrose hepática. É importante administrar a dose correcta de DMN e aderir ao esquema de injecções intraperitoneais semanalmente. À medida que a experiência progride, é crucial para pesar os ratos e re-cálculo da dose no início de cada semana de injecções DMN. Tenha em mente que DMN é tóxico e precisa ser tratado no gabinete de fumos. Nós as injecções intraperitoneais no gabinete fume bem. Com a nec...

DMN é uma toxina específica potente fígado. O seu metabolismo, distribuição nos tecidos, e a capacidade de provocar ferimentos aos fígados de ratos foi relatado por Magee 1, e o mecanismo de dano dos hepatócitos e a morte celular por apoptose foi descrito por Pritchard e Butler 2. Administração intermitente deste composto foi relatada para induzir a fibrose do fígado em cães e ratos 3,4. Os mecanismos e as alterações morfológicas da fibrose hepática têm sido amplamente estudados usando este modelo. Em estudos iniciais utilizando o rato, o tratamento de 3 semanas com DMN produziu necrose hemorrágica centrolobular seguido de cirrose micronodular sem esteatose 5. Foi demonstrado que, em fibrose precoce, o colagénio formada era mais ligações cruzadas com o tipo III ser mais proeminente do tipo I 6. Em comum com outras causas, alterações fibróticas induzida por DMN estavam associados com um aumento das células de Kupffer; macrófagos hepáticos que residem in sinusóides. Estas células transformar em miofibroblastos e produzem quantidades excessivas de matriz extracelular que é o principal problema na fibrose 7. Em termos de sinalização celular, Nakamura et ai. Demonstraram que o TGF-β desempenha um papel fundamental na progressão da fibrose hepática 8. Eles usaram um adenovírus que expressa um receptor truncado tipo II TGF-β, para inibir especificamente a sinalização de TGF-β. fibrose hepática nestes ratos foi espetacularmente interrompido durante o tratamento DMN quando comparado ao grupo controle. Outros estudos têm confirmado que a supressão do TGF-β leva até ao alívio de fígado desenvolvimento fibrose 9,10. O modelo também foi utilizado num estudo global perfil genético para identificar outros marcadores de fibrose e proteínas que podem ser utilizadas como alvos de drogas para a terapia anti-fibrótico 11. Outros agentes químicos usados ​​para induzir a fibrose do fígado incluem tioacetamida (TAA) e Ctetracloreto de Arbon (CCI4). TAA foi usado pela primeira vez em ratos e depois em ratos 12. As vantagens deste modelo incluem: a facilidade de administração química em água, a reprodutibilidade do modelo com cirrose micronodulares característica e alterações bioquímicas beber. As desvantagens incluem: o longo período de tempo de 3 meses para a fibrose hepática e para desenvolver a falta de compreensão do mecanismo molecular para a indução de fibrose hepática. Quanto CCI4, seu uso tem diminuído pelas seguintes razões: não imitar a doença de fígado humano, tem efeitos nocivos na camada de ozono, causa dor e sofrimento aos animais, é muito tóxico para os seres humanos e exige precauções extras em seu manuseio e eliminação 13,14. Obstrução do ducto biliar prolongada (por intervenção cirúrgica) como um modelo experimental para cirrose hepática foi relatada pela primeira vez por Kountouras et al. 15. Este método não é tóxico para os seres humanos e animais. Ho entanto, o tempo necessário para a fibrose do fígado a desenvolver varia. Uma revisão de 30 relatórios por Marques et al. 16, descobriu que ele tirou de sete dias a quatro semanas após a cirurgia para a fibrose do fígado para se desenvolver. As alterações patológicas descritas imitam os de fibrose biliar humana e crónica do modelo seria mais adequado para investigadores interessados ​​neste domínio. Em resumo, a administração intermitente de uma dose constante de DMN no rato ao longo de 4 semanas produz fibrose hepática que imita a doença humana. Ratos doseados mostram desenvolvimento progressivo de lesões no fígado e parênquima fibrose 4,17. Progressão e gravidade da doença pode ser monitorizado através de amostras de sangue ou de sacrifício dos animais a pontos de tempo específicos e o efeito é altamente reprodutível 18. Assim, o modelo tem sido amplamente utilizada para estudar os mecanismos de fibrose hepática e cirrose hepática, bem como para o rastreio de potenciais agentes anti-fibróticos 10,19,20.

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			<td>Dimethylnitrosamine</td>
			<td>Wako</td>
			<td>147-03781</td>
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			<td>Ethanol</td>
			<td>Sigma</td>
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			<td>Xylene</td>
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			<td>ALFA AESAR</td>
			<td>ALFA40116.4</td>
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			<td>Phosphomolybdic Acid Hydrate</td>
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			<td>Tissue processor</td>
			<td>Leica</td>
			<td>Leica TP 1020</td>
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			<td>Embedding machine</td>
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the dimethylnitrosamine induced liver fibrosis model in the rat

Quatro a seis semanas de idade, os ratos Wistar machos foram usados ​​para produzir modelos animais de fibrose hepática. O processo requer quatro semanas de administração de 10 mg / kg dimetilnitrosamina (DMN), administrado intraperitonealmente em três dias consecutivos por semana. As injecções intraperitoneais foram realizadas no exaustor de fumos, como é DMN um hepatoxin conhecida e cancerígeno. O modelo apresenta várias vantagens. Em primeiro lugar, alterações hepáticas podem ser estudadas sequencialmente ou em fases particulares de interesse. Em segundo lugar, do estágio da doença do fígado pode ser monitorizado pela medição de alanina aminotransferase (ALT) e aspartato aminotransferase (AST) enzimas. Em terceiro lugar, a gravidade dos danos no fígado em diferentes fases pode ser confirmada por sacrifício dos animais no ponto de tempo designado, seguido por exame histológico de tecidos do fígado corados Tricoma de Masson. Depois de quatro semanas de dosagem DMN, o marcador típico fibrose é de 5 a 6 na escala de Ishak. O modelo pode ser reproduzido de forma consistente e tem sidoamplamente utilizado para avaliar a eficácia de agentes anti-fibróticos potenciais.

DMN ratos tratados perder peso e se tornam menos vigorosa com pêlo arrepiou. Não há perda significativa nos pesos médios do corpo de ratos DMN tratada; primeiro detectável após 2 semanas de tratamento DMN, e essa diferença se mantém através semanas 3 e 4 após o tratamento DMN (Figura 1A). Como os ratos recebem DMN sobre semanas sucessivas, danos no fígado faz com que se torne menor. O índice de fígado; que é a percentagem de peso do fígado no peso corporal...

Watch this Scientific Journal Video about The Dimethylnitrosamine Induced Liver Fibrosis Model in the Rat at JoVE.com

The Dimethylnitrosamine Induced Liver Fibrosis Model in the Rat

We describe a method to produce an animal model of liver fibrosis in the rat, and assess the degree of fibrosis by histological examination of the liver. The model can be used to study the development of liver disease as well as to test the efficacy of potential anti-fibrotic agents.

A fibrose do fígado Modelo dimetilnitrosamina induzida no Rato

Four to six week old, male Wistar rats were used to produce animal models of liver fibrosis. The process requires four weeks of administration of 10 mg/kg ...

the-dimethylnitrosamine-induced-liver-fibrosis-model-in-the-rat

Research

JoVE Journal

Medicine

11.9K visualizações.  Temasek Polytechnic. We describe a method to produce an animal model of liver fibrosis in the rat, and assess the degree of fibrosis by histological examination of the liver. The model can be used to study the development of liver disease as well as to test the efficacy of potential anti-fibrotic agents.

Vídeo: The Dimethylnitrosamine Induced Liver Fibrosis Model in the Rat

A Model of Chronic Nutrient Infusion in the Rat

Chronic exposure to excessive levels of nutrients is postulated to affect the function of several organs and tissues and to contribute to the development of the many complications associated with obesity and the metabolic syndrome, including type 2 diabetes. To study the mechanisms by which excessive levels of glucose and fatty acids affect the pancreatic beta-cell and the secretion of insulin, we have established a chronic nutrient infusion model in the rat. The procedure consists of catheterizing the right jugular vein and left carotid artery under general anesthesia; allowing a 7-day recuperation period; connecting the catheters to the pumps using a swivel and counterweight system that enables the animal to move freely in the cage; and infusing glucose and/or Intralipid (a soybean oil emulsion which generates a mixture of approximately 80% unsaturated/20% saturated fatty acids when infused with heparin) for 72 hr. This model offers several advantages, including the possibility to finely modulate the target levels of circulating glucose and fatty acids; the option to co-infuse pharmacological compounds; and the relatively short time frame as opposed to dietary models. It can be used to examine the mechanisms of nutrient-induced dysfunction in a variety of organs and to test the effectiveness of drugs in this context.

A protocol for chronic infusions of glucose and Intralipid in rats is described. This model can be used to study the impact of nutrient excess on organ function and physiological parameters.

Um Modelo de Infusão Crónica de nutrientes no Rato

Chronic exposure to excessive levels of nutrients is postulated to  affect the function of several organs and tissues and to contribute to the  ...

Medicina

Tibial Nerve Transection - A Standardized Model for Denervation-induced Skeletal Muscle Atrophy in Mice

The tibial nerve transection model is a well-tolerated, validated, and reproducible model of denervation-induced skeletal muscle atrophy in rodents. Although originally developed and used extensively in the rat due to its larger size, the tibial nerve in mice is big enough that it can be easily manipulated with either crush or transection, leaving the peroneal and sural nerve branches of the sciatic nerve intact and thereby preserving their target muscles. Thus, this model offers the advantages of inducing less morbidity and impediment of ambulation than the sciatic nerve transection model and also allows investigators to study the physiologic, cellular and molecular biologic mechanisms regulating the process of muscle atrophy in genetically engineered mice. The tibial nerve supplies the gastrocnemius, soleus and plantaris muscles, so its transection permits the study of denervated skeletal muscle composed of fast twitch type II fibers and/or slow twitch type I fibers. Here we demonstrate the tibial nerve transection model in the C57Black6 mouse. We assess the atrophy of the gastrocnemius muscle, as a representative muscle, at 1, 2, and 4 weeks post-denervation by measuring muscle weights and fiber type specific cross-sectional area on paraffin-embedded histologic sections immunostained for fast twitch myosin.

The tibial nerve transection model is a well-tolerated, validated, and reproducible model of skeletal muscle atrophy. The model surgical protocol is described and demonstrated in C57Black6 mice. &#160;

Secção do nervo tibial - um modelo padronizado para denervação induzida por atrofia muscular em ratos

The tibial nerve transection model is a well-tolerated, validated, and reproducible model of denervation-induced skeletal muscle atrophy in rodents. ...

Method of Direct Segmental Intra-hepatic Delivery Using a Rat Liver Hilar Clamp Model

Major hepatic surgery with inflow occlusion, and liver transplantation, necessitate a period of warm ischemia, and a period of reperfusion leading to ischemia/reperfusion (I/R) injury with myriad negative consequences. Potential I/R injury in marginal organs destined for liver transplantation contributes to the current donor shortage secondary to a decreased organ utilization rate. A significant need exists to explore hepatic I/R injury in order to mediate its impact on graft function in transplantation. Rat liver hilar clamp models are used to investigate the impact of different molecules on hepatic I/R injury. Depending on the model, these molecules have been delivered using inhalation, epidural infusion, intraperitoneal injection, intravenous administration or injection into the peripheral superior mesenteric vein. A rat liver hilar clamp model has been developed for use in studying the impact of pharmacologic molecules in ameliorating I/R injury. The described model for rat liver hilar clamp includes direct cannulation of the portal supply to the ischemic hepatic segment via a side branch of the portal vein, allowing for direct segmental hepatic delivery. Our approach is to induce ischemia in the left lateral and median lobes for 60 min, during which time the substance under study is infused. In this case, pegylated-superoxide dismutase (PEG-SOD), a free radical scavenger, is infused directly into the ischemic segment. This series of experiments demonstrates that infusion of PEG-SOD is protective against hepatic I/R injury. Advantages of this approach include direct injection of the molecule into the ischemic segment with consequent decrease in volume of distribution and reduction in systemic side effects.

A unique rat liver hilar clamp model was developed for studying the impact of pharmacologic molecules in ameliorating ischemia-reperfusion injury. This model includes direct cannulation of the portal supply to the ischemic liver segment via a branch of the portal vein, allowing for direct hepatic delivery.

Método de entrega directa segmentos intra-hepática Usando um modelo de rato Liver Hilar Grampo

Major hepatic surgery with inflow occlusion, and liver transplantation, necessitate a period of warm ischemia, and a period of reperfusion leading to ...

Rat Model of the Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS) Procedure

Recent clinical data support an aggressive surgical approach to both primary and metastatic liver tumors. For some indications, like colorectal liver metastases, the amount of liver tissue left behind after liver resection has become the main limiting factor of resectability of large or multiple liver tumors. A minimal amount of functional tissue is required to avoid the severe complication of post-hepatectomy liver failure, which has high morbidity and mortality. Inducing liver growth of the prospective remnant prior to resection has become more established in liver surgery, either in the form of portal vein embolization by interventional radiologists or in the form of portal vein ligation several weeks prior to resection. Recently, it was shown that liver regeneration is more extensive and rapid, when the parenchymal transection is added to portal vein ligation in a first stage and then, after only one week of waiting, resection performed in a second stage (Associating Liver Partition and Portal vein ligation for Staged hepatectomy = ALPPS). ALPPS has rapidly become popular across the world, but has been criticized for its high perioperative mortality. The mechanism of accelerated and extensive growth induced by this procedure has not been well understood. Animal models have been developed to explore both the physiological and molecular mechanisms of accelerated liver regeneration in ALPPS. This protocol presents a rat model that allows mechanistic exploration of accelerated regeneration.

Rat Model of the Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy ALPPS Procedure

Inducing rapid liver hypertrophy using Associating Liver Partition and Portal vein ligation for a Staged hepatectomy (ALPPS) has been proposed for resection of borderline resectable liver tumors. This model may elucidate mechanisms involved in rapid hypertrophy and allows testing of drugs that promote or block the acceleration of regeneration.

Modelo do rato da partição fígado associando e ligadura da veia porta para procedimento encenado Hepatectomy (ALPPS)

Recent clinical data support an aggressive surgical approach to both primary and metastatic liver tumors. For some indications, like colorectal liver ...

Re-Arterialized Rat Partial Liver Transplantation with an in vivo Vessel-Oriented 70% Hepatectomy

Split liver transplantation and living liver donor liver transplantation were developed in the clinic to utilize liver organs in a more efficient manner. To better understand the mechanism behind these surgical procedures, a rat partial liver transplantation (PLTx) model was established for relevant surgical studies. Because of the complexity of the rat PLTx model, a protocol with detailed descriptions is required. An article published previously reported a protocol in which ex vivo hepatectomy was used to achieve 50% rat PLTx. In contrast to this protocol, we introduced a re-arterialized PLTx with an in vivo 70% hepatectomy. An updated vessel-oriented hepatectomy was incorporated into the rat PLTx to refine the microsurgical procedure. The portal veins and hepatic arteries of the left lateral lobe and the median lobe were individually dissected and ligated before removal of the liver parenchyma, thereby decreasing the probability of bleeding in the remnant liver stump. Furthermore, an end-to-side vessel anastomosis between the common hepatic artery and the enlarged proper hepatic artery was introduced to re-arterialize the hepatic artery. By using this end-to-side vessel anastomosis technique, the diameter of the anastomosis was enlarged, thereby decreasing the difficulty of hand suture and maintaining a high rate of anastomotic patency. Moreover, the cuff anastomosis of the infrahepatic vena cava was slightly modified. A section of circumferential liver parenchyma around the vena cava of a recipient was preserved during cuff anastomosis to maintain the three-dimensional shape of the vascular lumen. This section of liver parenchyma was removed after completing the anastomosis. With this modification, the step involving placement of stay sutures was omitted, thereby further shortening the cuff anastomosis time. By using this protocol of rat PLTx, a low liver enzyme level, an intact liver lobular architecture and a high survival rate were achieved after microsurgery.

Re-Arterialized Rat Partial Liver Transplantation with an in vivo Vessel-Oriented 70% Hepatectomy

Here, a protocol involving re-arterialized rat partial liver transplantation is presented. Specifically, 70% liver was resected in vivo by using an updated technique of vessel-oriented hepatectomy. The hepatic artery was reconstructed in an end-to-side manner. The cuff technique was modified to shorten the anastomosis time of the infrahepatic vena cava.

Re-Arterialized transplante de fígado parcial de rato com na vivo orientado a embarcação 70% Hepatectomy

Split liver transplantation and living liver donor liver transplantation were developed in the clinic to utilize liver organs in a more efficient manner. ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

Medição de contratilidade isométrica da artéria mesentérica Mouse usando fio miografia

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...

Left Atrial Stenosis Induced Pulmonary Venous Arterialization and Group 2 Pulmonary Hypertension in Rat

The mechanism of mitral stenosis-induced pulmonary venous arterialization and group 2 pulmonary hypertension (PH) is unclear. There is no rodent model of group 2 PH, due to mitral stenosis (MS), to facilitate the investigation of disease mechanisms and potential therapeutic strategies. We present a novel rat model of pulmonary venous congestion-induced pulmonary venous arterialization and group 2 PH caused by left atrial stenosis (LAS). LAS is achieved by constricting the left atrium using a half-closed titanium clip. After the LAS surgery, a rat model with a transmitral inflow velocity greater than or equal to 2.0 m/s on echocardiography gradually develops pulmonary venous arterialization and group 2 PH over an 8- to 10-week period. In this protocol, we provide the step-by-step procedure of how to perform the LAS surgery. The presented LAS rat model mimics MS in humans and is useful for studying the underlying molecular mechanism of pulmonary venous arterialization and for the preclinical evaluation of therapies for group 2 PH.

Left atrial stenosis (LAS) is a novel surgical technique used for studying group 2 pulmonary hypertension (PH) and mechanisms underlying pulmonary venous arterialization. Here, we present a protocol to constrict the left atrium using a titanium clip to cause pulmonary venous arterialization and moderate PH in a rat.

Estenose Atrial Esquerdo induzida Arterialization venoso pulmonar e hipertensão pulmonar do grupo 2 no rato

The mechanism of mitral stenosis-induced pulmonary venous arterialization and group 2 pulmonary hypertension (PH) is unclear. There is no rodent model of ...

Reduced Complications after Arterial Reconnection in a Rat Model of Orthotopic Liver Transplantation

The rat orthotopic liver transplantation (OLT) model is a powerful tool to study acute and chronic rejection. However, it is not a complete representation of human liver transplantation due to the absence of arterial reconnection. Described here is a modified transplantation procedure that includes the incorporation of hepatic artery (HA) reconnection, leading to a marked improvement in transplant outcomes. With a mean anhepatic time of 12 min and 14 s, HA reconnection results in improved perfusion of the transplanted liver and an increase in long-term recipient survival from 37.5% to 88.2%. This protocol includes the use of 3D-printed cuffs and holders to connect the portal vein and infrahepatic inferior vena cava. It can be implemented for studying multiple aspects of liver transplantation, from immune response and infection to technical aspects of the procedure. By incorporating a simple and practical method for arterial reconnection using a microvascular technique, this modified rat OLT protocol closely mimics aspects of human liver transplantation and will serve as a valuable and clinically relevant research model.

The goal of this study is to modify the rat orthotopic liver transplant model to better represent human liver transplantation and improve recipient survival. The presented method reestablishes hepatic arterial inflow by connecting the donor liver&#39;s common hepatic artery to the recipient liver&#39;s proper hepatic artery.

Complicações reduzidas após reconexão arterial em um modelo de rato de transplante de fígado ortotópico

The rat orthotopic liver transplantation (OLT) model is a powerful tool to study acute and chronic rejection. However, it is not a complete representation ...

Murine Precision-Cut Liver Slices as an Ex Vivo Model of Liver Biology

Understanding the mechanisms of liver injury, hepatic fibrosis, and cirrhosis that underlie chronic liver diseases (i.e., viral hepatitis, non-alcoholic fatty liver disease, metabolic liver disease, and liver cancer) requires experimental manipulation of animal models and in vitro cell cultures. Both techniques have limitations, such as the requirement of large numbers of animals for in vivo manipulation. However, in vitro cell cultures do not reproduce the structure and function of the multicellular hepatic environment. The use of precision-cut liver slices is a technique in which uniform slices of viable mouse liver are maintained in laboratory tissue culture for experimental manipulation. This technique occupies an experimental niche that exists between animal studies and in vitro cell culture methods. The presented protocol describes a straightforward and reliable method to isolate and culture precision-cut liver slices from mice. As an application of this technique, ex vivo liver slices are treated with bile acids to simulate cholestatic liver injury and ultimately assess the mechanisms of hepatic fibrogenesis.

This protocol provides a simple and reliable method for the production of viable precision-cut liver slices from mice. The ex vivo tissue samples can be maintained under laboratory tissue culture conditions for multiple days, providing a flexible model to examine liver pathobiology.

Murine Precision-Cut Liver Slices como um modelo ex vivo de biologia hepática

Understanding the mechanisms of liver injury, hepatic fibrosis, and cirrhosis that underlie chronic liver diseases (i.e., viral hepatitis, non-alcoholic ...

Organ Ischemia-Reperfusion Injury by Simulating Hemodynamic Changes in Rat Liver Transplant Model

Orthotopic liver transplantation (OLT) in rats is a tried and proven animal model used for preoperative, intraoperative, and postoperative studies, including ischemia-reperfusion injury (IRI) of extrahepatic organs. This model requires numerous experiments and devices. The duration of anhepatic phase is closely related to the time to develop IRI after transplantation. In this experiment, we used hemodynamic changes to induce extrahepatic organ damage in rats and determined the maximum tolerance time. The time until the most severe organ injury varied for different organs. This method can easily be replicated and can also be used to study IRI of the extrahepatic organs after liver transplantation.

This paper provides a detailed description of how to build an animal model of the anhepatic phase (liver ischemia) in rats to facilitate basic research into ischemia-reperfusion injury after liver transplantation.

Lesão por Isquemia-Reperfusão de Órgãos simulando alterações hemodinâmicas no modelo de transplante de fígado de rato

Orthotopic liver transplantation (OLT) in rats is a tried and proven animal model used for preoperative, intraoperative, and postoperative studies, ...