Este trabalho foi financiado pelo National Institutes of Health (R01DK58096 de Vincent Poitout). Vincent Poitout detém o Canada Research Chair em Diabetes e pâncreas a função das células beta. Bader Zarrouki receberam bolsas de pós-doutorado da Merck e Eli Lilly. Ghislaine Fontes foi apoiado por uma bolsa de pós-doutorado da Associação de Diabetes canadense.

Resumo: O procedimento consiste em cateterização da veia jugular direita e da artéria carótida esquerda, sob anestesia geral, permitindo um período de recuperação de 7 dias, permitindo a conexão dos cateteres para as bombas através de um suporte giratório e do sistema de contrapeso que permite que o animal se mover livremente na gaiola; e infusão de glicose e / ou Intralipid (uma emulsão de óleo de soja, que gera uma mistura de aproximadamente 80% unsaturated/20% de ácidos gordos saturados quando infundida com heparina 9) durante 72 horas. 1. Canulação da veia jugular direita e da artéria carótida esquerda <ol><li> Esterilizar instrumentos cirúrgicos. Tubagem de canulação também deve ser esterilizado a frio, utilizando um agente de esterilização líquido (2,6% de glutaraldeído) antes do procedimento. Mergulhe o tubo em um recipiente autoclavado por 16-24 horas. Enxágue e lave bem com água destilada estéril para remover todos os vestígios de glutaraldeído antes do uso. </li><li> Pesa-se o rato para calculardoses de droga: Carprofeno 5 mg / kg: diluição de 1/10 = Peso corporal (g) x 0,001 mL SC (analgésica) Glicopirroplato 0,01 mg / kg: diluição de 1/10 = BW (g) X 0,0012 ml de SC (anticolinérgicos) </li><li> Anestesiar o rato com isoflurano e oxigênio. </li><li> Coloque o rato em seu estômago. Raspar a área atrás das orelhas até à base dos ombros. Coloque o rato em suas costas. Raspar a região sob o pescoço com as patas dianteiras. </li><li> Preparação do local cirúrgico com clorexidina, álcool e iodo. Administrar drogas. </li><li> Transferir o rato para o campo cirúrgico. </li><li> Utilizando uma técnica asséptica, canulate a veia jugular direita e da artéria carótida esquerda, uma cânula de PE-50 ligado a uma seringa de 1 ml, cheio com 5 L de solução salina heparinizada. Lave as cânulas com 50 L de solução salina heparinizada para evitar a coagulação durante o período de recuperação. Use agulhas 23G embotados. Feche cada cânula com um pino de 23G. </li><li> Após a cirurgia, cortar cerca de 2,5 mm daincisivos inferiores e coloque o rato em uma jaqueta de infusão para evitar que as cânulas de ser comido. </li><li> Fornecer oxigénio (1 L / min durante 10 min) para ajudar a evacuar isoflurano. </li><li> Coloque o rato em uma gaiola aquecida até que esteja completamente desperto. </li><li> Operar quatro ratos para usar um por condição infusão (Tabela 1). </li></ol> 2. Pós-operatório Care (tratamento pós-cirúrgico e conexão dos cateteres) <ol><li> Pesar os animais no dia 1 e dia 2 pós-cirurgia. </li><li> Administrar glycopyrrolate (BW (g) x 0,00048 ml) SC duas vezes no 1 º dia pós-operatório e uma vez no dia 2 pós-cirurgia. </li><li> Tratamentos de suporte adicionais podem ser administradas, se necessário: fluidos, almofada de aquecimento, dieta molhado, oxigenoterapia, analgésicos, anticolinérgicos. </li><li> No dia 7 pós-operatório, pesar os ratos para calcular as taxas de fluxo de infusão. </li><li> Ligação cada rato para um sistema de infusão utilizando uma corda e giratória montada no topo de uma grade de gaiola (Figura 1).</li><li> Lave as cânulas com 5 L de solução salina heparinizada para remover coágulos. Lave as cânulas mais uma vez com 50 L de solução salina heparinizada para prevenir a coagulação. </li><li> Permitir que os ratos a aclimatar ao tirante e rodar, pelo menos, 24 horas antes do início da infusão. </li></ol> 3. Infusão <ol><li> Desenhar 0,15 ml de sangue a partir da carótida de cada rato e medir a glicemia. Lave as cânulas jugulares. Usar 50 L de solução salina heparinizada para evitar a coagulação em ambos os cânulas de cada rato. </li><li> Transferência da amostra de sangue para um tubo de 0,5 ml contendo 2% de recolha de EDTA. Centrifugar a 10.000 rpm durante 2 min e congelar o plasma a -20 ° C. </li><li> Encha duas seringas de 60 ml para cada uma das condições listadas abaixo de infusão. Seringa um lugar na posição da frente da bomba de seringa e local 2 na posição posterior da bomba. </li><li> Junte-se cada par de soluções em conjunto com y-conectores e tubos T22 CO-EX, que foi esterilizado. Coloque as seringas em uma Harvard 33Bomba de seringa dupla. </li><li> Altere o fundo da gaiola e retire todos os alimentos do topo da grade da gaiola. </li><li> Pesar 150 g de ração padrão e coloque sobre a grelha superior gaiola. </li><li> Ligue as seringas à peça giratória na grade da gaiola. Lave as seringas adequadamente para remover o ar retido a partir das linhas. </li><li> Calcular as taxas de fluxo de infusão que utilizam o peso corporal, que foi tomada antes de ligar o rato para o sistema de infusão. As tarifas são calculadas com um arquivo do Microsoft Excel que converte a taxa de infusão de glicose (GIR) em ml / h. </li><li> Defina a bomba para administrar as taxas de fluxo de 60 ml seringas de acordo com as definições do fabricante. Digite a taxa de Seringa 1 (seringa frente) ea taxa de Seringa 2 (back seringa). </li><li> Iniciar a bomba. </li></ol> 4. Monitoramento <ol><li> Depois de iniciar a bomba, verificar que não existe vazamento da peça giratória ou das cânulas de tubagem de infusão e que não é torcida. Verifique também se não há bolhas de ar naa tubagem. </li><li> Após 3 horas de infusão, tomar uma amostra de sangue para monitorar a glicemia. Repita depois de 6, 24, 48 e 72 horas de infusão. Como medida de precaução, a glicemia também é monitorada após 30, 34, 54 e 60 horas da infusão. Glucose no sangue pode ser medida utilizando uma gota de sangue completo, utilizando um monitor de glucose portátil. Isso limita a quantidade de sangue colhido durante a infusão e, por conseguinte, evita que altera significativamente o volume de sangue e / ou hematócrito. </li><li> A taxa de seringa 1 está modificado com base nos valores de glicemia para manter a glicose no sangue em 220-250 mg / dl. A taxa para Seringa dois não se altera durante a hr 72 de infusão, pois os ácidos graxos livres são mantidos em 1 mmol / L. </li><li> Condições de infusão são emparelhados de modo a que o volume recebido para os animais de controlo é equivalente ao volume recebido para os animais de ensaio (Tabela 1). </li><li> Após 24 horas de infusão, mudar o fundo da gaiola e pesar a comida restante na grade da gaiola. Retornar a parte restos de toa grelha gaiola. Repita depois de 48 horas. </li><li> Seringas de recarga diária, conforme necessário durante o hr 72 de infusão. </li><li> Durante a infusão, sempre observar o rato por quaisquer sinais de inflamação ou desconforto. Administrar os cuidados adequados, se necessário. </li></ol> 5. Eutanásia pós-infusão <ol><li class="jove_content"> Após 72 horas de infusão, os ratos são anestesiados por via intravenosa, com 0,5 ml de um cocktail de cetamina / xilazina (182 mg / kg de cetamina e de 11,6 mg / kg de xilazina diluída 1:2 com 0,9% de NaCl). </li><li class="jove_content"> O reflexo toe-pitada é utilizado para verificar o nível de anestesia. Adicional anestésico é administrado como necessário. </li><li class="jove_content"> Quando o rato é anestesiado, a cavidade abdominal é aberta com uma tesoura cirúrgica. O rato é sangrados através da elaboração de 10-15 ml de sangue numa seringa a partir da aorta ou da veia cava. </li></ol>

<ol>
	<li>Poitout, V., Robertson, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glucolipotoxicity:+fuel+excess+and+beta-cell+dysfunction.">Glucolipotoxicity: fuel excess and beta-cell dysfunction.</a> Endocr. Rev. 29, 351-366 (2008).</li><li>Poitout, V., 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=Glucolipotoxicity+of+the+pancreatic+beta+cell.">Glucolipotoxicity of the pancreatic beta cell.</a> Biochim. Biophys. Acta. 1801, 289-298 (2010).</li><li>Unger, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Minireview:+weapons+of+lean+body+mass+destruction:+the+role+of+ectopic+lipids+in+the+metabolic+syndrome.">Minireview: weapons of lean body mass destruction: the role of ectopic lipids in the metabolic syndrome.</a> Endocrinology. 144, 5159-5165 (2003).</li><li>Harmon, J. S., Gleason, C. E., Tanaka, Y., Poitout, V., Robertson, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antecedent+hyperglycemia,+not+hyperlipidemia,+is+associated+with+increased+islet+triacylglycerol+content+and+decreased+insulin+gene+mRNA+level+in+Zucker+diabetic+fatty+rats.">Antecedent hyperglycemia, not hyperlipidemia, is associated with increased islet triacylglycerol content and decreased insulin gene mRNA level in Zucker diabetic fatty rats.</a> Diabetes. 50, 2481-2486 (2001).</li><li>Bachar, E., Ariav, Y., Cerasi, E., Kaiser, N., Leibowitz, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neuronal+nitric+oxide+synthase+protects+the+pancreatic+beta+cell+from+glucolipotoxicity-induced+endoplasmic+reticulum+stress+and+apoptosis.">Neuronal nitric oxide synthase protects the pancreatic beta cell from glucolipotoxicity-induced endoplasmic reticulum stress and apoptosis.</a> Diabetologia. 53, 2177-2187 (2010).</li><li>Peyot, M. L., 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=Beta-cell+failure+in+diet-induced+obese+mice+stratified+according+to+body+weight+gain:+secretory+dysfunction+and+altered+islet+lipid+metabolism+without+steatosis+or+reduced+beta-cell+mass.">Beta-cell failure in diet-induced obese mice stratified according to body weight gain: secretory dysfunction and altered islet lipid metabolism without steatosis or reduced beta-cell mass.</a> Diabetes. 59, 2178-2187 (2010).</li><li>Hagman, D. 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=Cyclical+and+alternating+infusions+of+glucose+and+intralipid+in+rats+inhibit+insulin+gene+expression+and+Pdx-1+binding+in+islets.">Cyclical and alternating infusions of glucose and intralipid in rats inhibit insulin gene expression and Pdx-1 binding in islets.</a> Diabetes. 57, 424-431 (2008).</li><li>Fontes, G., 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=Glucolipotoxicity+age-dependently+impairs+beta+cell+function+in+rats+despite+a+marked+increase+in+beta+cell+mass.">Glucolipotoxicity age-dependently impairs beta cell function in rats despite a marked increase in beta cell mass.</a> Diabetologia. 53, 2369-2379 (2010).</li><li>Stein, D. T., 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=Essentiality+of+circulating+fatty+acids+for+glucose-stimulated+insulin+secretion+in+the+fasted+rat.">Essentiality of circulating fatty acids for glucose-stimulated insulin secretion in the fasted rat.</a> J. Clin. Invest. 97, 2728-2735 (1996).</li><li>Leahy, J. L., Cooper, H. E., Weir, G. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impaired+insulin+secretion+associated+with+near+normoglycemia.+Study+in+normal+rats+with+96-h+in+vivo+glucose+infusions.">Impaired insulin secretion associated with near normoglycemia. Study in normal rats with 96-h in vivo glucose infusions.</a> Diabetes. 36, 459-464 (1987).</li><li>Hager, S. R., Jochen, A. L., Kalkhoff, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insulin+resistance+in+normal+rats+infused+with+glucose+for+72+h.">Insulin resistance in normal rats infused with glucose for 72 h.</a> The American Journal of Physiology. 260, 353-362 (1991).</li><li>Laybutt, D. R., Chisholm, D. J., Kraegen, E. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specific+adaptations+in+muscle+and+adipose+tissue+in+response+to+chronic+systemic+glucose+oversupply+in+rats.">Specific adaptations in muscle and adipose tissue in response to chronic systemic glucose oversupply in rats.</a> The American Journal of Physiology. 273, E1-E9 (1997).</li><li>Jonas, J. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+glucose+stimulates+early+response+gene+c-Myc+expression+in+rat+pancreatic+beta+cells.">High glucose stimulates early response gene c-Myc expression in rat pancreatic beta cells.</a> The Journal of Biological Chemistry. 276, 35375-35381 (2001).</li><li>Tang, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glucose-induced+beta+cell+dysfunction+in+vivo+in+rats:+link+between+oxidative+stress+and+endoplasmic+reticulum+stress.">Glucose-induced beta cell dysfunction in vivo in rats: link between oxidative stress and endoplasmic reticulum stress.</a> Diabetologia. 55, 1366-1379 (2012).</li><li>Alonso, L. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glucose+infusion+in+mice:+a+new+model+to+induce+beta-cell+replication.">Glucose infusion in mice: a new model to induce beta-cell replication.</a> Diabetes. 56, 1792-1801 (2007).</li><li>Magnan, C., Gilbert, M., Kahn, B. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+free+fatty+acid+infusion+in+rats+results+in+insulin+resistance+but+no+alteration+in+insulin-responsive+glucose+transporter+levels+in+skeletal+muscle.">Chronic free fatty acid infusion in rats results in insulin resistance but no alteration in insulin-responsive glucose transporter levels in skeletal muscle.</a> Lipids. 31, 1141-1149 (1996).</li><li>Goh, T. T., 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=Lipid-induced+beta-cell+dysfunction+in+vivo+in+models+of+progressive+beta-cell+failure.">Lipid-induced beta-cell dysfunction in vivo in models of progressive beta-cell failure.</a> Am. J. Physiol. Endocrinol. Metab. 292, 549-560 (2007).</li><li>Pascoe, 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=Free+fatty+acids+block+glucose-induced+beta-cell+proliferation+in+mice+by+inducing+cell+cycle+inhibitors+p16+and+p18.">Free fatty acids block glucose-induced beta-cell proliferation in mice by inducing cell cycle inhibitors p16 and p18.</a> Diabetes. 61, 632-641 (2012).</li><li>Bell, C. G., Walley, A. J., Froguel, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+genetics+of+human+obesity.">The genetics of human obesity.</a> Nature Reviews. Genetics. 6, 221-234 (2005).</li><li>Fontes, G., Hagman, D. K., Latour, M. G., Semache, M., Poitout, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lack+of+preservation+of+insulin+gene+expression+by+a+glucagon-like+peptide+1+agonist+or+a+dipeptidyl+peptidase+4+inhibitor+in+an+in+vivo+model+of+glucolipotoxicity.">Lack of preservation of insulin gene expression by a glucagon-like peptide 1 agonist or a dipeptidyl peptidase 4 inhibitor in an in vivo model of glucolipotoxicity.</a> Diabetes Res. Clin. Pract. 87, 322-328 (2010).</li><li>Crawford, P. A., Schaffer, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metabolic+stress+in+the+myocardium:+Adaptations+of+gene+expression.">Metabolic stress in the myocardium: Adaptations of gene expression.</a> Journal of Molecular and Cellular Cardiology. , (2012).</li><li>Kewalramani, G., Bilan, P. J., Klip, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Muscle+insulin+resistance:+assault+by+lipids,+cytokines+and+local+macrophages.">Muscle insulin resistance: assault by lipids, cytokines and local macrophages.</a> Curr. Opin. Clin. Nutr. Metab Care. 13, 382-390 (2010).</li><li>Cusi, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+obesity+and+lipotoxicity+in+the+development+of+nonalcoholic+steatohepatitis:+pathophysiology+and+clinical+implications.">Role of obesity and lipotoxicity in the development of nonalcoholic steatohepatitis: pathophysiology and clinical implications.</a> Gastroenterology. 142, 711-725 (2012).</li></ol>

Vincent Poitout é co-fundador e recebeu contratos de investigação a partir de Bêtagenex Inc., uma organização de pesquisa de contrato, que oferece o modelo de infusão apresentada neste artigo como um serviço comercial.

Embora um certo número de estudos anteriores têm utilizado infusões crónicas de glicose (por exemplo, 10-15) ou lípidos (por exemplo, 16,17) em roedores, para o nosso conhecimento da infusão conjunta de ambos os combustíveis apenas foi avaliado em ratos 18. O modelo de infusão crónica aqui apresentado oferece diversas vantagens para o estudo dos efeitos sobre o excesso de nutrientes de uma variedade de funções biológicas em ratos. Primeiro, ele não envolve ...

Os níveis cronicamente elevados de glucose e lípidos na circulação têm sido propostos para contribuir para a patogénese da diabetes tipo 2 alterando a função de vários órgãos implicados na manutenção da homeostase da glucose, incluindo, mas não limitado a, o das células beta do pâncreas (revisto em 1). Os glicotoxicidade hipótese postula que a hiperglicemia crônica agrava o defeito das células beta que deu origem à hiperglicemia, em primeiro lugar, criando assim um ciclo vicioso e contribuindo para a deterioração do controle da glicose em pacientes diabéticos tipo 2. Da mesma forma, a hipótese propõe que as elevações glucolipotoxicity concomitantes dos níveis de glucose e lípidos, como frequentemente observadas em pacientes com diabetes tipo 2, são prejudiciais para a célula beta. Decifrar os mecanismos celulares e moleculares dos efeitos deletérios de nutrientes cronicamente elevados sobre a função das células beta do pâncreas é fundamental para o understanding da patogénese da diabetes de tipo 2 1. Para esse efeito, um grande número de estudos examinaram os mecanismos de nutrientes em excesso ex vivo crónica nas ilhotas de Langerhans isoladas ou in vitro, em linhas de células secretoras de insulina clonais. Contudo, a tradução dos resultados obtidos nestes sistemas modelo para todo o organismo é complexo, em especial, porque as concentrações de ácidos gordos utilizados na cultura de células ou ilhotas raramente igualar os níveis de circulação in vivo de 2 a vizinhança das células beta. Por outro lado, os mecanismos de falha das células beta em resposta ao excesso de nutrientes foram examinados em modelos de roedores da diabetes, tal como exemplificado pelo rato Zucker Diabetic Fatty 3,4, o gerbilo Psammomys obesus 5 e o elevado teor de gordura da dieta fed rato 6. Estes modelos, no entanto, são caracterizados por anormalidades metabólicas intrínsecas e não são facilmente adaptado às manipulações da glicose no sanguee / ou os níveis de lipídeos em um ambiente mais controlado e menos crônica. Para ser capaz de alterar os níveis circulantes de nutrientes num período de tempo de dias em animais normais em contrário, nós desenvolvemos um modelo de infusão crónica em ratos normais, o que nos permite examinar os efeitos de lípidos e de glucose, sozinho ou em combinação, sobre os parâmetros fisiológicos e função 7,8.

<table border="1">
		<tbody>
		 <tr>
			<td>Name of Reagent/Material</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		 </tr>
		 <tr>
			<td>Saline 0.9%</td>
			<td>BD</td>
			<td>JB1324</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Dextrose 70%</td>
			<td>McKesson</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>Intralipid 20%</td>
			<td>Fresenius Kabi</td>
			<td>JB6023</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Metricide (Glutaraldehyde 2.6%)</td>
			<td>Metrex</td>
			<td>11-1401</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Heparin Sodium 10,000 USP u/ml</td>
			<td>PPC</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>Carprofen</td>
			<td>Metacam</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>Glycopyrrolate</td>
			<td>Sandoz</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>Isoflurane</td>
			<td>Abbott</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>Chlohexidine 2%</td>
			<td></td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>Alcohol 70%</td>
			<td></td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>Iodine</td>
			<td></td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>PE-50</td>
			<td>BD</td>
			<td>427411</td>
			<td></td>
		 </tr>
		 <tr>
			<td>CO-EX T22</td>
			<td>Instech Solomon</td>
			<td>BCOEX-T22</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Connector 22G</td>
			<td>Instech Solomon</td>
			<td>SC22/15</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Swivel 22G</td>
			<td>Instech Solomon</td>
			<td>375/22PS</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Y-Connector 22G</td>
			<td>Instech Solomon</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>Counterbalance and arm</td>
			<td>Instech Solomon</td>
			<td>CM375BP</td>
			<td></td>
		 </tr>
		 <tr>
			<td>23 G blunted needles</td>
			<td>Instech Solomon</td>
			<td>LS23</td>
			<td></td>
		 </tr>
		 <tr>
			<td>23 G canulation pins</td>
			<td>Instech Solomon</td>
			<td>SP23/12</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Tethers (12 inch)</td>
			<td>Lomir</td>
			<td>RT12D</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Infusion jackets </td>
			<td>Lomir</td>
			<td>RJ01, RJ02, RJ03, RJ04</td>
			<td></td>
		 </tr>
		 <tr>
			<td>(SM-XL)</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Tether attachment piece</td>
			<td>Lomir</td>
			<td>RS T1</td>
			<td></td>
		 </tr>
		 <tr>
			<td>60 ml syringe</td>
			<td>BD</td>
			<td>309653</td>
			<td></td>
		 </tr>
		 <tr>
			<td>1 ml syringe</td>
			<td>BD</td>
			<td>309602</td>
			<td></td>
		 </tr>
		</tbody>
 </table>

a model of chronic nutrient infusion in the rat

A exposição crónica a níveis excessivos de nutrientes é postulada para afectar a função de vários órgãos e tecidos, e para contribuir para o desenvolvimento de muitas complicações associadas à obesidade e à síndrome metabólica, incluindo diabetes tipo 2. Para estudar os mecanismos pelos quais os níveis excessivos de glucose e ácidos gordos afectam o das células beta do pâncreas e da secreção de insulina, criámos um modelo de infusão de nutrientes crónica no rato. O procedimento consiste em cateterização da veia jugular direita e da artéria carótida esquerda, sob anestesia geral, permitindo um período de recuperação de 7 dias, permitindo a conexão dos cateteres para as bombas através de um suporte giratório e do sistema de contrapeso que permite que o animal se mover livremente na gaiola, e infundindo glicose e / ou Intralipid (uma emulsão de óleo de soja, que gera uma mistura de aproximadamente 80% unsaturated/20% de ácidos gordos saturados quando infundida com heparina) durante 72 horas. Este modelo oferece vários advantages, incluindo a possibilidade de modular finamente os níveis alvo de glicose e os ácidos gordos de circulação, a opção de co-infundir compostos farmacológicos, e o período de tempo relativamente curto em oposição aos modelos dietéticos. Ele pode ser usado para examinar os mecanismos de disfunção de nutrientes induzida por uma variedade de órgãos e para testar a eficácia de drogas neste contexto.

De uma série de 42 ratos, que foram submetidos à cirurgia, cinco ratos foram perdidos durante o período pós-operatório e um rato foi perdida durante a infusão, o que representa uma taxa de sucesso global de 86%. O peso corporal médio dos 37 ratos que eventualmente foram infundidos foi 608 ± 5 g, antes da cirurgia e 588 ± 6 g no início da perfusão (média ± EP, n = 37, P &lt;0,0001 por teste t emparelhado). Os seguintes resultados representativos foram obtidos em dois grupos: de infusão. Saline (SAL) e glico...

Watch this Scientific Journal Video about A Model of Chronic Nutrient Infusion in the Rat at JoVE.com

A Model of Chronic Nutrient Infusion in the Rat

Um protocolo para as infusões crónicas de glicose e Intralipid no rato é descrito. Este modelo pode ser utilizado para estudar o impacto do excesso de nutrientes sobre a função do órgão de parâmetros fisiológicos.

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  ...

a-model-of-chronic-nutrient-infusion-in-the-rat

Research

JoVE Journal

Medicine

12.6K visualizações.  CRCHUM. Um protocolo para as infusões crónicas de glicose e Intralipid no rato é descrito. Este modelo pode ser utilizado para estudar o impacto do excesso de nutrientes sobre a função do órgão de parâmetros fisiológicos.

Vídeo: A Model of Chronic Nutrient Infusion in the Rat

Orthotopic Aortic Transplantation: A Rat Model to Study the Development of Chronic Vasculopathy

Research models of chronic rejection are essential to investigate pathobiological and pathophysiological processes during the development of transplant vasculopathy (TVP).
The commonly used animal model for cardiovascular chronic rejection studies is the heterotopic heart transplant model performed in laboratory rodents. This model is used widely in experiments since Ono and Lindsey (3) published their technique. To analyze the findings in the blood vessels, the heart has to be sectioned and all vessels have to be measured.
Another method to investigate chronic rejection in cardiovascular questionings is the aortic transplant model (1, 2). In the orthotopic aortic transplant model, the aorta can easily be histologically evaluated (2). The PVG-to-ACI model is especially useful for CAV studies, since acute vascular rejection is not a major confounding factor and Cyclosporin A (CsA) treatment does not prevent the development of CAV, similar to what we find in the clinical setting (4). A7-day period of CsA is required in this model to prevent acute rejection and to achieve long-term survival with the development of TVP.
This model can also be used to investigate acute cellular rejection and media necrosis in xenogeneic models (5).

This video demonstrates the orthotopic aortic transplant model as a simple model to study the development of transplant vasculopathy (TVP) in rats.

Transplante ortotópico de aorta: um modelo de rato para estudar o desenvolvimento de vasculopatia crônica

Research models of chronic rejection are essential to investigate pathobiological and pathophysiological processes during the development of transplant ...

Medicina

5/6th Nephrectomy in Combination with High Salt Diet and Nitric Oxide Synthase Inhibition to Induce Chronic Kidney Disease in the Lewis Rat

Chronic kidney disease (CKD) is a global problem. Slowing CKD progression is a major health priority. Since CKD is characterized by complex derangements of homeostasis, integrative animal models are necessary to study development and progression of CKD. To study development of CKD and novel therapeutic interventions in CKD, we use the 5/6th nephrectomy ablation model, a well known experimental model of progressive renal disease, resembling several aspects of human CKD. The gross reduction in renal mass causes progressive glomerular and tubulo-interstitial injury, loss of remnant nephrons and development of systemic and glomerular hypertension. It is also associated with progressive intrarenal capillary loss, inflammation and glomerulosclerosis. Risk factors for CKD invariably impact on endothelial function. To mimic this, we combine removal of 5/6th of renal mass with nitric oxide (NO) depletion and a high salt diet. After arrival and acclimatization, animals receive a NO synthase inhibitor (NG-nitro-L-Arginine) (L-NNA) supplemented to drinking water (20 mg/L) for a period of 4 weeks, followed by right sided uninephrectomy. One week later, a subtotal nephrectomy (SNX) is performed on the left side. After SNX, animals are allowed to recover for two days followed by LNNA in drinking water (20 mg/L) for a further period of 4 weeks. A high salt diet (6%), supplemented in ground chow (see time line Figure 1), is continued throughout the experiment. Progression of renal failure is followed over time by measuring plasma urea, systolic blood pressure and proteinuria. By six weeks after SNX, renal failure has developed. Renal function is measured using 'gold standard' inulin and para-amino hippuric acid (PAH) clearance technology. This model of CKD is characterized by a reduction in glomerular filtration rate (GFR) and effective renal plasma flow (ERPF), hypertension (systolic blood pressure&gt;150 mmHg), proteinuria (&gt; 50 mg/24 hr) and mild uremia (&gt;10 mM). Histological features include tubulo-interstitial damage reflected by inflammation, tubular atrophy and fibrosis and focal glomerulosclerosis leading to massive reduction of healthy glomeruli within the remnant population (&lt;10%). Follow-up until 12 weeks after SNX shows further progression of CKD.

A two-stage method to establish chronic kidney disease (CKD) in the Lewis rat by surgically removing 5/6th of renal mass is described. Combination of the surgical procedure, NOS-inhibition and a high-salt diet leads to a model resembling human CKD, allowing study of causal mechanisms and development of novel therapeutic interventions.

5/6th Nephrectomy em combinação com uma dieta alta de sal e Óxido Nítrico Sintase inibição para induzir o Doença Renal Crônica no Rato Lewis

Chronic kidney disease (CKD) is a global problem. Slowing CKD progression is a major health priority. Since CKD is characterized by complex derangements ...

Urinary Bladder Distention Evoked Visceromotor Responses as a Model for Bladder Pain in Mice

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition characterized by increased urgency and frequency of urination, as well as nocturia and general pelvic pain, especially upon bladder filling or voiding. Despite years of research, the cause of IC/BPS remains elusive and treatment strategies are unable to provide complete relief to patients. In order to study nervous system contributions to the condition, many animal models have been developed to mimic the pain and symptoms associated with IC/BPS. One such murine model is urinary bladder distension (UBD). In this model, compressed air of a specific pressure is delivered to the bladder of a lightly anesthetized animal over a set period of time. Throughout the procedure, wires in the superior oblique abdominal muscles record electrical activity from the muscle. This activity is known as the visceromotor response (VMR) and is a reliable and reproducible measure of nociception. Here, we describe the steps necessary to perform this technique in mice including surgical manipulations, physiological recording, and data analysis. With the use of this model, the coordination between primary sensory neurons, spinal cord secondary afferents, and higher central nervous system areas involved in bladder pain can be unraveled. This basic science knowledge can then be clinically translated to treat patients suffering from IC/BPS.

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition characterized in part by pelvic pain. In order to study nervous system contributions to the condition, a physiological model of urinary bladder pain is used in mice and rats.

Respostas Bexiga Distensão Evocado Visceromotor como um modelo para Bexiga dor em camundongos

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition ...

Slow-release Drug Delivery through Elvax 40W to the Rat Retina: Implications for the Treatment of Chronic Conditions

Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these diseases. Chronic retinal diseases such as retinal oedema or neovascularization usually require multiple intraocular injections to effectively treat the condition. However, the risks associated with these injections increase with repeated delivery of the drug. Therefore, alternative delivery methods need to be established in order to minimize the risks of reinjection. Several other investigations have developed methods to deliver drugs over extended time, through materials capable of releasing chemicals slowly into the eye. In this investigation, we outline the use of Elvax 40W, a copolymer resin, to act as a vehicle for drug delivery to the adult rat retina. The resin is made and loaded with the drug. The drug-resin complex is then implanted into the vitreous cavity, where it will slowly release the drug over time. This method was tested using 2-amino-4-phosphonobutyrate (APB), a glutamate analogue that blocks the light response of the retina. It was demonstrated that the APB was slowly released from the resin, and was able to block the retinal response by 7 days after implantation. This indicates that slow-release drug delivery using this copolymer resin is effective for treating the retina, and could be used therapeutically with further testing.

This paper details how Elvax 40W can be used as a slow-release method for drug delivery to the adult rat retina. The protocol for preparing, loading, and delivering the drug-resin complex to the eye is described.

De liberação lenta Drug Delivery através Elvax 40W para o Rat Retina: implicações para o tratamento de condições crônicas

Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these ...

Neurodegeneration in an Animal Model of Chronic Amyloid-beta Oligomer Infusion Is Counteracted by Antibody Treatment Infused with Osmotic Pumps

Decline in hippocampal-dependent explicit memory (memory for facts and events) is one of the earliest clinical symptom of Alzheimer&#39;s disease (AD). It is well established that synapse loss and ensuing neurodegeneration are the best predictors for memory impairments in AD. Latest studies have emphasized the neurotoxic role of soluble amyloid-beta oligomers (A&#946;o) that begin to accumulate in the human brain approximately 10 to 15 yr before the clinical symptoms become apparent. Many reports indicate that soluble A&#946;o correlate with memory deficits in AD models and humans. The A&#946;o-induced neurodegeneration observed in neuronal and brain slice cultures has been more challenging to reproduce in many animal models. The model of repeated A&#946;o infusions shown here overcome this issue and allow addressing two key domains for developing new disease modifying therapies: identify biological markers to diagnose early AD, and determine the molecular mechanisms underpinning A&#946;o-induced memory deficits at the onset of AD. Since soluble A&#946;o aggregate relatively fast into insoluble A&#946; fibrils that correlate poorly with the clinical state of patients, soluble A&#946;o are prepared freshly and injected once per day during six days to produce marked cell death in the hippocampus. We used cannula specially design for simultaneous infusions of A&#946;o and continuous infusion of A&#946;o antibody (6E10) in the hippocampus using osmotic pumps. This innovative in vivo method can now be used in preclinical studies to validate the efficiency of new AD therapies that might prevent the deposition and neurotoxicity of A&#946;o in pre-dementia patients.

To study the effects of A&#946;o in vivo, we developed a model based on repeated hippocampal infusions of soluble A&#946;o coupled with continuous infusion of A&#946;o antibody (6E10) in the hippocampus using osmotic pumps to counteract the neurotoxic effect of A&#946;o.

Neurodegeneração em um modelo animal de Chronic beta-amilóide Oligï¿½ero Infusion é contrariada pelo anticorpo Tratamento infundido com bombas osmóticas

Decline in hippocampal-dependent explicit memory (memory for facts and events) is one of the earliest clinical symptom of Alzheimer&#39;s disease (AD). It ...

Use of a Central Venous Line for Fluids, Drugs and Nutrient Administration in a Mouse Model of Critical Illness

This protocol describes a centrally catheterized mouse model of prolonged critical illness. We combine the cecal ligation and puncture method to induce sepsis with the use of a central venous line for fluids, drugs and nutrient administration to mimic the human clinical setting. Critically ill patients require intensive medical support in order to survive. While the majority of patients will recover within a few days, about a quarter of the patients need prolonged intensive care and are at high risk of dying from non-resolving multiple organ failure. Furthermore, the prolonged phase of critical illness is hallmarked by profound muscle weakness, and endocrine and metabolic changes, of which the pathogenesis is currently incompletely understood. The most widely used animal model in critical care research is the cecal ligation and puncture model to induce sepsis. This is a very reproducible model, with acute inflammatory and hemodynamic changes similar to human sepsis, which is designed to study the acute phase of critical illness. However, this model is hallmarked by a high lethality, which is different from the clinical human situation, and is not developed to study the prolonged phase of critical illness. Therefore, we adapted the technique by placing a central venous catheter in the jugular vein allowing us to administer clinically relevant supportive care, to better mimic the human clinical situation of critical illness. This mouse model requires an extensive surgical procedure and daily intensive care of the animals, but it results in a relevant model of the acute and prolonged phase of critical illness.

This protocol describes a centrally catheterized mouse model of prolonged critical illness. We combine the cecal ligation and puncture method to induce sepsis with the use of a central venous line for fluids, drugs and nutrient administration to mimic the human clinical setting.

O uso de um cateter venoso central para fluidos, drogas e Administração de nutrientes em um modelo do rato da doença crítica

This protocol describes a centrally catheterized mouse model of prolonged critical illness. We combine the cecal ligation and puncture method to induce ...

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 ...

A New Best Practice for Validating Tail Vein Injections in Rat with Near-infrared-Labeled Agents

Intravenous (IV) administration of agents into the tail vein of rats can be both difficult and inconsistent. Optimizing tail vein injections is a key part of many experimental procedures where reagents need to be introduced directly into the bloodstream. Unwittingly, the injection can be subcutaneous, possibly altering the scientific outcomes. Utilizing a nanoemulsion-based biological probe with an incorporated near-infrared fluorescent (NIRF) dye, this method offers the capability of imaging a successful tail vein injection in vivo. With the use of a NIRF imager, images are taken before and after the injection of the agent. An acceptable IV injection is then qualitatively or quantitatively determined based on the intensity of the NIRF signal at the site of injection.

Here we present a method to validate tail vein injections in rats by utilizing near-infrared fluorescence imaging data from dyes incorporated into agents or biological probes. The tail is imaged before and after the injection, the fluorescent signal is quantified, and an assessment of the injection quality is made.

Nova prática recomendada para validar a cauda veia injeções no rato com agentes próximo-infravermelho-rotulado

Intravenous (IV) administration of agents into the tail vein of rats can be both difficult and inconsistent. Optimizing tail vein injections is a key part ...

Acupuncture in a Rat Model of Asthma

A high platform can fix rats without restriction and completely expose the acupoints on the back during acupuncture manipulation. This article describes methods for the fabrication of the high platform, establishes a rat model of asthma and measures changes in respiratory function using a noninvasive and real-time whole-body plethysmography (WBP) system.

Acupuntura em um modelo de rato de asma

A high platform can fix rats without restriction and completely expose the acupoints on the back during acupuncture manipulation. This article describes ...

A Mouse Model for Chronic Pancreatitis via Bile Duct TNBS Infusion

Chronic pancreatitis (CP) is a complex disease involving pancreatic inflammation and fibrosis, glandular atrophy, abdominal pain and other symptoms. Several rodent models have been developed to study CP, of which the bile duct 2,4,6 -trinitrobenzene sulfonic acid (TNBS) infusion model replicates the features of neuropathic pain seen in CP. However, bile duct drug infusion in mice is technically challenging. This protocol demonstrates the procedure of bile duct TNBS infusion for generation of a CP mouse model. TNBS was infused into the pancreas through the ampulla of Vater in the duodenum. This protocol optimized drug volume, surgical techniques, and drug handling during the procedure. TNBS-treated mice showed features of CP as reflected by bodyweight and pancreas weight reductions, changes in pain-associated behaviors, and abnormal pancreatic morphology. With these improvements, mortality associated with TNBS injection was minimal. This procedure is not only critical in generating pancreatic disease models but is also useful in local pancreatic drug delivery.

Chronic pancreatitis (CP) is a disease characterized by inflammation and fibrosis of the pancreas, often associated with intractable abdominal pain. This article focuses on refining the technique to generate a mouse model of CP via bile duct infusion with 2,4,6 -trinitrobenzene sulfonic acid (TNBS).

Um modelo de rato para pancreatite crônica através da infusão TNBS do ducto biliar

Chronic pancreatitis (CP) is a complex disease involving pancreatic inflammation and fibrosis, glandular atrophy, abdominal pain and other symptoms. ...