Name: surgical models of gastroesophageal reflux with mice
Uploaded: 2015-08-25T15:00:00.000+00:00
Duration: 5 min 19 s
Description: Watch this Scientific Journal Video about Surgical Models of Gastroesophageal Reflux with Mice at JoVE.com

We are supported by research grants from the National Natural Science Foundation of China (NO. 81400590), National Institutes of Health (U54 CA156735) and Takeda Pharmaceutical Company Ltd. (MA-NC-D-156).

Todas as experiências com animais foram aprovados pelo Comitê de Cuidado e Uso do animal Institucional. 1. Preparação do rato <ol><li> Use camundongos mais ~ 20 g no peso corporal ou superiores a 6 semanas de idade para a cirurgia. </li><li> Antes da cirurgia, dar camundongos um laboratório de comida e água ad libitum e manter em um ciclo claro-escuro de 00:12 h. </li><li> Raspar a área cirúrgica com uma máquina de cortar cabelo. Anestesiar ratos por injecção intraperitoneal de 80 mg / kg de cetamina e 12 mg / kg de xilazina. Esta dose coloca ratos no sono em poucos minutos e fornece anestesia suficiente para os seguintes procedimentos cirúrgicos. </li><li> Confirme anesthetization adequada com base na ausência do reflexo corneal e retração membro quando a pata é comprimido. Aplicar lubrificante pomada oftálmica nos olhos para evitar o ressecamento. </li><li> Esterilizar a pele com solução de betadine. </li></ol> 2. Modelo refluxo gástrico (Figura 1B) <ol><li> Realizar uma superiorincisão na linha média de ~ 2 cm a partir da xifóide apontando para o ânus. </li><li> Abra-se a cavidade abdominal através da linha média. Remova o xifóide para aumentar a exposição com um par de tesouras. </li><li> Separa-se e cortar os tecidos conjuntivos entre o fígado e o estômago. Ligadura e cortar o feixe vascular entre o baço e do fundo, a fim de completamente livre até o fundo. </li><li> Ligue o fundo ligeiramente para a esquerda e expor o lado esquerdo da junção gastro-esofágico no campo. Adicione uma incisão longitudinal de 5 mm no músculo distai ao longo do esófago utilizando um par de tesouras para expor o epitélio. </li><li> Corte aberto do epitélio ao longo da mesma direcção (incisão 1, Figura 1B). Adicione três incisões na pança de incisão (2, 3 e 4, Figura 1B) para eliminar a maioria da pança com uma tesoura afiada operacionais. Se o estômago não está vazio, remova cuidadosamente o conteúdo gástrico. </li><li> Coloque um Sutu prolene 8-0re (com um ponto de afunilamento agulha) através de um ponto (no esôfago) e ponto A &#39;(na pança) com uma precisão de mucosa da mucosa oposição. De igual modo lugar suturas através do ponto b e Ponto b &#39;, e outros pares de pontos, respectivamente. Uniformemente espaço estas suturas 3-4 mm uns dos outros. </li><li> Lava-se a cavidade abdominal com solução salina normal para limpar o sangue e o conteúdo gástrico. Feche a parede abdominal com fio de seda e pele com grampos metálicos. </li></ol> 3. Modelo de Refluxo mistos (Figura 1C) <ol><li> Siga os passos 2.1 a 2.4 para expor a junção gastroesofágico. </li><li> Suavemente separar o lado dorsal do esófago a partir dos vasos sanguíneos por trás do esófago. Passe uma ponta de algodão pequena entre os vasos sanguíneos e esôfago. Nota: O algodão pode ser parcialmente removida a partir da ponta para reduzir o seu tamanho. Esta dica de algodão serve a dois propósitos, levantando o esôfago e proteger os vasos sanguíneos. </li><li> Faça inc dois cinco milímetros longitudinalisions cada na junção gastro-esofágico e a extremidade proximal do duodeno adjacente ao piloro com uma tesoura afiada operacionais. Para a incisão no duodeno, evitar vasos sanguíneos e coloque na fronteira anti-mesentérica. </li><li> Anastomosar as incisões com mucosa com precisão de mucosas oposição interrompidas 8-0 suturas de Prolene. Normalmente coloque 3-4 suturas na face dorsal e 2-3 suturas na parte da frente. </li><li> Retire a ponta de algodão. Lava-se a cavidade abdominal com solução salina normal e fechar a parede abdominal e a pele. </li></ol> 4. Modelo Duodenal refluxo (Figura 1D) <ol><li> Siga o passo 3.1 a 3.4 para gerar misto de refluxo. </li><li> Com cuidado, levante o estômago para expor a sua parte de trás. Um lobo do fígado podem ser abrangidos pelo tecido conjuntivo entre o fígado e parte de trás do estômago. Corte cuidadosamente os tecidos conjuntivos, corretamente proteger o fígado, e expor os vasos sanguíneos no lado dorsal do esôfago. </li><li> Ligadura ecortar os vasos sanguíneos. Ligadura e cortado o esófago na junção gastroesofágico. </li><li> Ligar o duodeno no piloro. Ligadura e cortar o mesentério. Remover todo o estômago. </li><li> Lava-se a cavidade abdominal com solução salina normal. Fechar a parede abdominal e a pele. </li></ol> 5. O tratamento pós-cirúrgico <ol><li> Após a cirurgia manter a temperatura corporal com uma almofada de aquecimento. Só depois de recuperar decúbito esternal, coloque os ratos de volta com outros animais. </li><li> Dar antibióticos e analgésicos para prevenir a infecção e aliviar a dor. Injectar Baytril (10 mg / kg, ip, qd, durante 3 dias) para prevenir a infecção, e cloridrato de buprenorfina (0,05 mg / kg, sc, bid. Dois dias) como analgésico. O jejum não é necessário após a cirurgia. A dieta líquida ou mole pode ser dada. </li><li> Avaliar o estado de saúde geral sobre basis.If diários os ratos mostram os seguintes sinais (dramática perda de peso&gt; 15%, a falta de appetite, vocalização, descarregar a partir da boca, nariz ou olhos, gesto curvado, inatividade, atividade aliciamento anormal), sacrificar os ratos. </li></ol>

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	<li>Kandulski, A., Malfertheiner, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gastroesophageal+reflux+disease--from+reflux+episodes+to+mucosal+inflammation.">Gastroesophageal reflux disease--from reflux episodes to mucosal inflammation.</a> Nat Rev Gastroenterol Hepatol. 9 (1), 15-22 (2012).</li><li>Orlando, 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=The+integrity+of+the+esophageal+mucosa.+Balance+between+offensive+and+defensive+mechanisms.">The integrity of the esophageal mucosa. Balance between offensive and defensive mechanisms.</a> Best Pract Res Clin Gastroenterol. 24 (6), 873-882 (2010).</li><li>Stairs, D. B., Kong, J., Lynch, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cdx+genes,+inflammation,+and+the+pathogenesis+of+intestinal+metaplasia.">Cdx genes, inflammation, and the pathogenesis of intestinal metaplasia.</a> Prog Mol Biol Transl Sci. 96, 231-270 (2010).</li><li>Spechler, S. J., Fitzgerald, R. C., Prasad, G. A., History Wang, K. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=molecular+mechanisms,+and+endoscopic+treatment+of+Barrett's+esophagus.">molecular mechanisms, and endoscopic treatment of Barrett's esophagus.</a> Gastroenterology. 138 (3), 854-869 (2010).</li><li>Fang, Y., 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=Cellular+origins+and+molecular+mechanisms+of+Barrett's+esophagus+and+esophageal+adenocarcinoma.">Cellular origins and molecular mechanisms of Barrett's esophagus and esophageal adenocarcinoma.</a> Ann N Y Acad Sci. 1300, 187-199 (2013).</li><li>Garman, K. S., Orlando, R. C., Chen, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review:+Experimental+models+for+Barrett's+esophagus+and+esophageal+adenocarcinoma.">Review: Experimental models for Barrett's esophagus and esophageal adenocarcinoma.</a> Am J Physiol Gastrointest Liver Physiol. 302 (11), G1231-G1243 (2012).</li><li>Baruah, 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=Translational+research+on+Barrett's+esophagus.">Translational research on Barrett's esophagus.</a> Ann N Y Acad Sci. 1325, 170-186 (2014).</li><li>Lechpammer, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flavopiridol+reduces+malignant+transformation+of+the+esophageal+mucosa+in+p27+knockout+mice.">Flavopiridol reduces malignant transformation of the esophageal mucosa in p27 knockout mice.</a> Oncogene. 24 (10), 1683-1688 (2005).</li><li>Hao, J., Liu, B., Yang, C. S., Chen, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gastroesophageal+reflux+leads+to+esophageal+cancer+in+a+surgical+model+with+mice.">Gastroesophageal reflux leads to esophageal cancer in a surgical model with mice.</a> BMC Gastroenterol. 9, 59 (2009).</li><li>Mari, 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=A+pSMAD/CDX2+complex+is+essential+for+the+intestinalization+of+epithelial+metaplasia.">A pSMAD/CDX2 complex is essential for the intestinalization of epithelial metaplasia.</a> Cell Rep. 7 (4), 1197-1210 (2014).</li><li>Fang, Y., 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=Gastroesophageal+reflux+activates+the+NF-kappaB+pathway+and+impairs+esophageal+barrier+function+in+mice.">Gastroesophageal reflux activates the NF-kappaB pathway and impairs esophageal barrier function in mice.</a> Am J Physiol Gastrointest Liver Physiol. 305 (1), G58-G65 (2013).</li><li>Chen, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nrf2+deficiency+impairs+the+barrier+function+of+mouse+oesophageal+epithelium.">Nrf2 deficiency impairs the barrier function of mouse oesophageal epithelium.</a> Gut. 63 (5), 711-719 (2014).</li></ol>

One of the authors (XC) received funding that was provided by Takeda Pharmaceutical Company Ltd which supports basic research associated with gastroesophageal reflux disease. None of the reagents or instruments used in this article is produced by this company.

Vários modelos cirúrgicos foram criados para imitar gástrica, duodenal e misto de refluxo em roedores. Estes três procedimentos aqui descritos são adequados para experimentos de longo prazo com taxas razoáveis ​​de sobrevivência pós-operatória. Um pesquisador com experiência cirúrgica deve ser capaz de compreender a técnica, após um curto período de prática. A hemorragia pode resultar de injecção intraperitoneal de anestésicos antes da cirurgia, laceração do fígado durante a separação dos tecidos conjuntivos entre o fígado e do estômago, e danos inadvertidos dos vasos sanguíneos. Isso deve ser evitado tanto quanto possível. Operado por bateria mini-cautério pode ser utilizado para parar o sangramento, se apropriado. Alongamento excessivo deve ser evitado, tanto quanto possível quando os órgãos e tecidos são manipulados. As pontas das pinças pode ser envolto com algodão, ou pontas de algodão podem ser utilizados para substituir pauzinhos como pinças. O esôfago do rato tem duas camadas ou duas &amp; #8220; tubos &quot;, avermelhado exterior&quot; tubo muscular &quot;e esbranquiçada interior&quot; tubo epitélio &quot;. Quando é feita uma incisão no esófago, ambas as camadas devem ser cortado e aberto. Suturas devem ser uniformemente espaçados com precisão de mucosa da mucosa oposição. O vazamento pode resultar de uma ampla distância entre as suturas, enquanto estenose pode desenvolver-se devido a uma distância estreita entre as suturas. No entanto, a crítica pode bloquear a passagem dos alimentos e causar a morte de pós-operatório, ao passo que um pequeno derrame pode ser fixado por adesão local e reação fibrótica e, portanto, geralmente não é fatal. Existem vários princípios criticamente gerais a serem seguidas no âmbito do protocolo. A duração da cirurgia deve ser encurtado se possível (cerca de 20-30 minutos no laboratório). Jejum antes e após a cirurgia é desnecessária. Na verdade, jejum prolongado (&gt; 1 dia) pode ser prejudicial. A cirurgia é melhor executada por um único cirurgião. Um assistente pode ajudar a anestesiar os ratos e fornecer surgmateriais iCal. Um microscópio não é necessário a menos que o cirurgião tenha sido devidamente treinado em microcirurgia. Caso contrário, a duração da cirurgia tende a ser maior do que o necessário e, portanto, a sobrevivência pós-operatória pode ser potencialmente pior. Estes procedimentos foram utilizados em publicações anteriores e geraram resultados satisfatórios. Usando de tipo selvagem e camundongos geneticamente modificados, demonstramos que NFkB e Nrf2 vias regulada a função de barreira do epitélio do esôfago durante o refluxo gastro-esofágico 11,12. No entanto, não foram capazes de produzir esôfago ou adenocarcinoma full-blown de Barrett nesses camundongos, em vez disso, as células espalhadas mucinoso e carcinoma de células escamosas foram induzidos 9. Diferenças histológicas entre esôfago do rato e do esôfago humano podem ser as limitações inerentes a esses modelos cirúrgicos na pesquisa sobre adenocarcinoma de esôfago e esôfago de Barrett. Nós acreditamos que estes surgical modelos são úteis para estudos sobre DRGE. Funções de genes e vias moleculares pode ser elucidada para compreender os mecanismos moleculares de RGE e desenvolver a terapia baseada em mecanismo. Quando usado para a produção de adenocarcinoma do esófago de Barrett e esofágica, serão necessárias modificações genéticas em combinação com a cirurgia de refluxo.

Gastroesophageal reflux disease (GERD) is a chronic disorder caused by the prolonged exposure of distal esophagus to gastric or gastroduodenal contents1. Prolonged exposure to these noxious refluxates impairs the intrinsic defenses within the esophageal epithelium and thus results in esophagitis2. Barrett&#8217;s esophagus arises in the setting of chronic reflux, and is a premalignant lesion with increased risk of esophageal adenocarcinoma3,4. Despite the clinical importance, the mechanisms of GERD, Barrett&#8217;s esophagus and adenocarcinoma have not been well understood. 
Animal models are essential for research on etiology, pathology, molecular mechanisms, prevention and treatment of human diseases. Up to date, various animal models of GERD, Barrett&#8217;s esophagus and adenocarcinoma have been developed using model animals5,6. Mouse esophagus is lined with stratified squamous epithelium which is histologically similar to that in human esophagus. Although a mouse esophagus is different from human esophagus in terms of keratinization and the absence of submucosal glands, the mouse is still an appealing model animal because of its relatively low cost of maintenance and its potential of sophisticated genetic modifications. Two approaches are commonly used to model GERD, Barrett&#8217;s esophagus and adenocarcinoma in mice: reflux surgery and genetic modification. Reflux surgery is the best way to induce reflux and genetic modifications mimics molecular alterations5,7. Reflux surgery can be combined with genetic modifications to further understand disease mechanisms8. 
Many surgical procedures have been reported by us and others6,9: (1) gastric reflux: pyloric ligation, pyloric constriction with forestomach ligation, Wendel cardioplasty, and esophagogastric anastomosis; (2) mixed reflux: esophagogastroduodenal anastomosis, esophagoduodenostomy (or esophagojejunostomy); (3) duodenal reflux: esophagogastroduodenal anastomosis plus gastrectomy; (4) reflux of chemical components: bilious reflux, pancreatic reflux, esophageal perfusion; and (5) esophageal transplantation5. Recently a microsurgical mouse model was reported to produce jejunal reflux via an esophagojejunostomy with magnets10. These surgical models have advantages over in vitro cell culture or organotypic culture models. In vitro, esophageal cells cannot tolerate a medium with high acidity or high concentrations of bile acids. Unconjugated bile acids which are commonly used to produce changes in esophageal epithelial cells in vitro are usually not present in the duodenal refluxate in vivo. Thus conclusions drawn from such in vitro studies should be taken with caution.
Surgery on the mouse esophagus remains a technical challenge because of its small size. A low rate of postoperative survival does not allow experiments which require certain sample size to reach statistically sound conclusions. In the past we have successfully developed and characterized surgical models of gastric reflux, mixed reflux, duodenal reflux with mice in long-term experiments9,11,12. We have also provided consultation to several other groups in their mouse surgery. Herein, we describe three surgical procedures in mice in order to help the community to establish these models in their labs.

<table><tbody><tr><td>Dumont #1 Forceps Dumostar Tip&amp;nbsp;</td><td>Roboz Surgical Instrument Co. (Gaithersburg, MD)</td><td></td><td></td></tr><tr><td>Micro Clip Applying Forceps 5.5&quot;</td><td>Roboz Surgical Instrument Co. (Gaithersburg, MD)</td><td></td><td></td></tr><tr><td>Bonn Scissors 3.5&quot; Straight 15 mm Sharp/Sharp Tungsten Carbide Blades</td><td>Roboz Surgical Instrument Co. (Gaithersburg, MD)</td><td></td><td></td></tr><tr><td>Operating Scissors 5.5&quot; Straight Sharp/Sharp SureCut</td><td>Roboz Surgical Instrument Co. (Gaithersburg, MD)</td><td></td><td></td></tr><tr><td>4-0 Silk Black Braid 100 Yard Spool</td><td>Roboz Surgical Instrument Co. (Gaithersburg, MD)</td><td></td><td></td></tr><tr><td>Surgeon&#039;s Needle 1/2 Circle Cutting Edge Size 12 (25 mm Chord Length) Pack 12</td><td>Roboz Surgical Instrument Co. (Gaithersburg, MD)</td><td></td><td></td></tr><tr><td>Halsey Needle Holder 5&quot; Smooth</td><td>Roboz Surgical Instrument Co. (Gaithersburg, MD)</td><td></td><td></td></tr><tr><td>Micro Needle Holder 5.125&quot; Curved Lock .6 mm</td><td>Roboz Surgical Instrument Co. (Gaithersburg, MD)</td><td></td><td></td></tr><tr><td>Reflex 9 mm Wound Clip Applier</td><td>Roboz Surgical Instrument Co. (Gaithersburg, MD)</td><td></td><td></td></tr><tr><td>Reflex 9 mm Wound Clips Box Of 100</td><td>Roboz Surgical Instrument Co. (Gaithersburg, MD)</td><td></td><td></td></tr><tr><td>PRONOVA Poly (hexafluoropropylene-VDF) Suture 8-0</td><td>Ethicon US, LLC</td><td></td><td></td></tr><tr><td>Ringer&#039;s solution</td><td>Henry Schein, Inc.</td><td></td><td></td></tr><tr><td>ketamine</td><td>Henry Schein, Inc.</td><td></td><td></td></tr><tr><td>xylazine</td><td>Henry Schein, Inc.</td><td></td><td></td></tr></tbody></table>

surgical models of gastroesophageal reflux with mice

Multiple surgical procedures have been reported to induce gastroesophageal reflux in animals. Herein, we report three surgical models with mice aiming to induce reflux of gastric contents, duodenal contents or mixed contents. Surgical procedures and general principles have been described in detail. A researcher with surgical experience should be able to grasp the technique after a short period of practice. After surgery, most mice can survive and develop reflux esophagitis similar to that in humans. However, it should be noted that histological differences between mouse and human esophagus are the inherent limitations of these surgical models. If used for research on Barrett&#8217;s esophagus and adenocarcinoma, these procedures may need to be combined with genetic modifications.

A maioria dos ratinhos (&gt; 95%) pode sobreviver à cirurgia. Durante o período perioperatório, as principais causas de morte incluem overdose de anestésicos, sangramento e razões desconhecidas. Quatro semanas após a cirurgia,&gt; 90% de ratinhos com refluxo gástrico ou misto de refluxo e&gt; 80% de ratinhos com refluxo duodenal podem sobreviver. Durante este período, os ratos morrem principalmente de estenose esofágica e incapacidade para comer. Estes ratos mostram sinais de estresse grave (postura arqueada, a inatividade, vômitos, olhos encovados, vocalização, etc.) e precisam ser sacrificados. O tratamento médico com antibióticos e infusão geralmente não pode salvar estes ratos de morrer. Ratos geralmente perdem seu peso corporal por um par de gramas após a cirurgia, especialmente aqueles com refluxo duodenal. Não obstante o peso corporal vai se recuperar e aumentar mais tarde. Quarenta dias após a cirurgia,&gt; 80% de ratinhos com refluxo gástrico e misturado e&gt; 70% de ratinhos com refluxo duodenal podem sobreviver. During este período, alguns ratos podem morrer de desnutrição ou razões desconhecidas. Mantivemos ratos durante 80 semanas após a cirurgia. Em geral, eles ainda são muito ativos e saudáveis ​​9. Às quatro semanas após a cirurgia, a arquitetura do epitélio esofágico será danificado mais ou menos por refluxo. Sob o microscópio, o epitélio torna-se mais espessa e a papila alonga. Hiperproliferação das células epiteliais e infiltração de células inflamatórias (por exemplo, neutrófilos, eosinófilos e mastócitos) são sinais óbvios de esofagite (Figura 2). As citocinas em epitélio esofágico (por exemplo, IL1β, IL6 e IL8) são particularmente elevados, na presença de refluxo duodenal 11. Sob microscopia eletrônica de transmissão, espaço intercelular dilatado reflete o comprometimento da função barreira epitelial 12. Função-sábio, resistência eléctrica trans-epitelial é drasticamente diminuída, especialmente na presença de duodenrefluxo ai. <img alt="Figura 1" src="/files/ftp_upload/53012/53012fig1.jpg" /> Figura 1: (A) Anatomia do trato digestivo superior em ratinhos (vista frontal e lateral); (B) refluxo gástrico (vista lateral); (C) refluxo Misto (vista frontal); (D) refluxo Duodenal (vista de frente). <img alt="Figura 2" src="/files/ftp_upload/53012/53012fig2.jpg" /> Figura 2: Histologia de rato sem epitélio esofágica de refluxo (A), ou com refluxo gástrico (B), misto de refluxo (C), refluxo duodeno (D). Barra de escala = 50 mm.

Watch this Scientific Journal Video about Surgical Models of Gastroesophageal Reflux with Mice at JoVE.com

Surgical Models of Gastroesophageal Reflux with Mice

This article demonstrates surgical procedures of gastroesophageal reflux with mice. These models are useful tools for research on mechanisms and treatment of gastroesophageal reflux disease and potentially Barrett&#8217;s esophagus and esophageal adenocarcinoma.

Modelos cirúrgicos de refluxo gastroesofágico com Ratos

Multiple surgical procedures have been reported to induce gastroesophageal reflux in animals. Herein, we report three surgical models with mice aiming to ...

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Nanyang Technological University

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JoVE Journal

Medicine

10.0K visualizações.  Ningxia Medical University General Hospital. This article demonstrates surgical procedures of gastroesophageal reflux with mice. These models are useful tools for research on mechanisms and treatment of gastroesophageal reflux disease and potentially Barrett’s esophagus and esophageal adenocarcinoma.

Vídeo: Surgical Models of Gastroesophageal Reflux with Mice

Mouse Models Of Helicobacter Infection And Gastric Pathologies

Helicobacter pylori is a gastric pathogen that is present in half of the global population and is a significant cause of morbidity and mortality in humans. Several mouse models of gastric Helicobacter infection have been developed to study the molecular and cellular mechanisms whereby H. pylori bacteria colonize the stomach of human hosts and cause disease. Herein, we describe protocols to: 1) prepare bacterial suspensions for the in vivo infection of mice via intragastric gavage; 2) determine bacterial colonization levels in mouse gastric tissues, by polymerase chain reaction (PCR) and viable counting; and 3) assess pathological changes, by histology. To establish Helicobacter infection in mice, specific pathogen-free (SPF) animals are first inoculated with suspensions (containing &#8805;105 colony-forming units, CFUs) of mouse-colonizing strains of either Helicobacter pylori or other gastric Helicobacter spp. from animals, such as Helicobacter felis. At the appropriate time-points post-infection, stomachs are excised and dissected sagittally into two equal tissue fragments, each comprising the antrum and body regions. One of these fragments is then used for either viable counting or DNA extraction, while the other is subjected to histological processing. Bacterial colonization and histopathological changes in the stomach may be assessed routinely in gastric tissue sections stained with Warthin-Starry, Giemsa or Haematoxylin and Eosin (H&#38;E) stains, as appropriate. Additional immunological analyses may also be undertaken by immunohistochemistry or immunofluorescence on mouse gastric tissue sections. The protocols described below are specifically designed to enable the assessment in mice of gastric pathologies resembling those in human-related H. pylori diseases, including inflammation, gland atrophy and lymphoid follicle formation. The inoculum preparation and intragastric gavage protocols may also be adapted to study the pathogenesis of other enteric human pathogens that colonize mice, such as Salmonella Typhimurium or Citrobacter rodentium.

Mouse Models Of Helicobacter Infection And Gastric Pathologies

Mice represent an invaluable in vivo model to study infection and diseases caused by gastrointestinal microorganisms. Here, we describe the methods used to study bacterial colonization and histopathological changes in mouse models of Helicobacter pylori-related disease.

Modelos de mouse da infecção por Helicobacter e patologias gástricas

Helicobacter pylori is a gastric pathogen that is present in half of the global population and is a significant cause of morbidity and mortality in ...

Imunologia e Infecção

Techniques of Sleeve Gastrectomy and Modified Roux-en-Y Gastric Bypass in Mice

Obesity is a major public health issue, with a prevalence of 4 to 28% for men and 6.2 to 36.5% for women in Europe (from 2003 to 2008). Morbid obesity is frequently associated with metabolic complications, such as type 2 diabetes, hypertension, and dyslipidemia, reducing life expectancy and quality. In the absence of any effective noninvasive treatments, bariatric surgery is a valuable therapeutic option for patients with morbid obesity (body mass index (BMI) &#62;40 kg/m2), leading to long-term, sustained weight loss and improvements in metabolic complications. However, the underlying cellular and molecular mechanisms sustaining the beneficial effects of bariatric surgery are not yet fully understood. Due to the numerous genetically-modified strains available, the mouse model is the most convenient animal model to explore the molecular mechanisms behind the pleiotropic beneficial effects of bariatric surgeries. Here, we detailed the optimized healthcare methods and surgical protocols in mice for the two most widely-used bariatric surgeries: the sleeve gastrectomy and the modified Roux-en-Y gastric bypass. Deciphering the molecular mechanisms underlying the therapeutic effects of bariatric surgeries offers the promise of identifying new therapeutics targets.

Bariatric surgery is the most efficient way to reduce body weight and the deadly metabolic complications (diabetes, obesity, and dyslipidemia) frequently associated with morbid obesity. Mouse models of bariatric surgery represent a unique asset for deciphering molecular mechanisms behind the beneficial effects of these surgeries on diabetes, hypertension, and dyslipidemia.

Técnicas de gastrectomia vertical e modificado Roux-en-Y bypass gástrico em ratos

Obesity is a major public health issue, with a prevalence of 4 to 28% for men and 6.2 to 36.5% for women in Europe (from 2003 to 2008). Morbid obesity is ...

Medicina

Creation of Colonic Anastomosis in Mice

Intestinal anastomoses are commonly performed in both elective and emergent operations. Even so, anastomotic leaks are a highly feared complications of colonic surgeries and can occur in up to 26% of surgical anastomoses, with mortality being up to 39% for patients with such a leak. Currently, there remains a paucity of data detailing the cellular mechanisms of anastomotic healing. Devising preventative strategies and treatment modalities for anastomotic leak could be greatly potentiated by a better understanding of appropriate anastomotic healing.
A murine model is ideal as previous studies have shown that the murine anastomosis is the most clinically similar to the human case as compared with other animal models. We offer an easily reproducible murine model of colonic anastomosis in mice that will allow for further illustration of anastomotic healing.

Anastomotic leak or breakdown after surgery is a major cause of postoperative morbidity and mortality. Our surgery for creating a colonic anastomosis is a reliable and reproducible method for studying the healing mechanisms of anastomoses.

Criação de uma anastomose colônica em ratos

Intestinal anastomoses are commonly performed in both elective and emergent operations. Even so, anastomotic leaks are a highly feared complications of ...

Sleeve Gastrectomy in Mice using Surgical Clips

The number of people who are overweight and obese is continually increasing both in the adult and adolescent populations. This coincides with the increased universal phenomenon of type 2 diabetes (T2D) and other metabolic problems. Bariatric surgery, such as SG, is currently one of the most effective and commonly used long-term treatment for obesity and T2D, but the association between them is not completely explored yet. The mechanisms underlying the outcomes seen after bariatric surgery in humans can be investigated based on preclinical animal studies. The SG reduces body weight, glucose levels and many metabolic parameters, and is easy to perform with a low incidence of complications. The goal of this work is to provide a simple method and an uncomplicated preclinical model of bariatric surgery in animals for researchers.

The prevalence of diabetes and obesity is continuously increasing worldwide. The mechanisms between diabetes, obesity and their associated mortality and co-morbidities need to be further investigated. Here, we present a protocol for sleeve gastrectomy (SG) in animals as an uncomplicated preclinical model of bariatric surgery.

Gastrectomia de manga em camundongos usando clipes cirúrgicos

The number of people who are overweight and obese is continually increasing both in the adult and adolescent populations. This coincides with the ...

<meta charset="utf8"></head><body>Modelo Murino para Estudo do Íleo Secundário Pós-Operatório por Manipulação Intestinal

Postoperative Ileus Murine Model

Most patients experience postoperative ileus (POI) after surgery, which is associated with increased morbidity, mortality, and hospitalization time. POI is a consequence of mechanical damage during surgery, resulting in disruption of motility in the gastrointestinal tract. The mechanisms of POI are related to aberrant neuronal sensitivity, impaired epithelial barrier function, and increased local inflammation. However, the details remain enigmatic. Therefore, experimental murine models are crucial for elucidating the pathophysiology and mechanism of POI injury and for the development of novel therapies.
Here, we introduce a murine model of POI generated via intestinal manipulation (IM) that is similar to clinical surgery; this is achieved by mechanical damage to the small intestine by massaging the abdomen 1-3 times with a cotton swab. IM delayed gastrointestinal transit 24 h after surgery, as assessed by FITC-dextran gavage and fluorescence detection of the segmental digestive tract. Moreover, tissue swelling of the submucosa and immune cell infiltration were investigated by hematoxylin and eosin staining and flow cytometry. Proper pressure of the IM and a hyperemic effect on the intestine are critical for the procedure. This murine model of POI can be utilized to study the mechanisms of intestinal damage and recovery after abdominal surgery.

<meta charset="utf8"></head><body>Modelo Murino de Íleo Pós-Operatório

We describe a murine model of postoperative ileus generated via intestinal manipulation. Gastrointestinal transit function, pathologic changes, and immune cell activation were assessed 24 h after surgery.

Modelo Murino de Íleo Pós-Operatório

Most patients experience postoperative ileus (POI) after surgery, which is associated with increased morbidity, mortality, and hospitalization time. POI ...

Single-Anastomosis Duodeno-Ileal Bypass with Sleeve Gastrectomy Model in Mice

Obesity is a major health issue worldwide. As a response, bariatric surgeries have emerged to treat obesity and its related comorbidities (e.g., diabetes mellitus, dyslipidemia, non-alcoholic steatohepatitis, cardiovascular events, and cancers) through restrictive and malabsorptive mechanisms. Understanding the mechanisms by which these procedures allow such improvements often require their transposition into animals, especially in mice, because of the ease of generating genetically modified animals. Recently, the single-anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) has emerged as a procedure that uses both restrictive and malabsorptive effects, which is being used as an alternative to gastric bypass in case of major obesity. Thus far, this procedure has been associated with strong metabolic improvements, which has led to a marked increase in its use in daily clinical practice. However, the mechanisms underlying these metabolic effects have been poorly studied as a result of a lack of animal models. In this article, we present a reliable and reproducible model of SADI-S in mice, with a special focus on perioperative management. The description and use of this new rodent model will be helpful for the scientific community to better understand the molecular, metabolic, and structural changes induced by the SADI-S and to better define the surgical indications for clinical practice.

Single-anastomosis duodeno-ileal bypass (SADI-S) is an emerging bariatric procedure with important metabolic effects. In this article, we present a reliable and reproducible model of SADI-S in mice.

Modelo de Bypass Duodeno-Ileal de Anastomose Única com Gastrectomia Vertical em Camundongos

Obesity is a major health issue worldwide. As a response, bariatric surgeries have emerged to treat obesity and its related comorbidities (e.g., diabetes ...

A Murine Model of Vertical Sleeve Gastrectomy

Bariatric surgery, such as vertical sleeve gastrectomy (VSG), is a surgery of the gastrointestinal tract that is performed for the purpose of weight loss. Bariatric surgery is currently the most effective long-term treatment for obesity. In addition to weight loss, bariatric surgery produces additional health benefits such as remission of type 2 diabetes, remission of hypertension, and decreased risk of developing certain types of cancer. The mechanisms beyond weight loss for these benefits remain incompletely defined. Therefore, animal models of bariatric surgery are being developed and validated to identify the mechanisms leading to these benefits, with the goal of improving understanding of gastrointestinal physiology and identifying new therapeutic targets. VSG has become the most commonly performed bariatric procedure in the clinic in the United States because it is highly effective at producing weight loss and metabolic improvement, and is simpler to perform than other bariatric procedures. Therefore, we have developed and validated a murine model of VSG. This murine VSG model recapitulates many of the effects of VSG seen in humans, including improved glucose and blood pressure regulation. The method is based on isolation of the stomach, ligation of gastric vessels, and removal of 70% of the stomach by transecting along the greater curvature of the stomach. We have successfully applied this surgical protocol to various genetically modified mouse lines to define the mechanistic contributors to the benefits of VSG. Furthermore, this murine VSG model has been combined with other surgical techniques, to achieve deeper mechanistic insight. Therefore, this is a simple and versatile model for studying gastrointestinal physiology and the health benefits of bariatric surgery.

The following describes the performance of vertical sleeve gastrectomy in mice. This is a type of weight-loss surgery that involves removal of approximately 70% of the stomach.

Um modelo murino de gastrectomia de manga Vertical

Bariatric surgery, such as vertical sleeve gastrectomy (VSG), is a surgery of the gastrointestinal tract that is performed for the purpose of weight loss. ...

Biologia

A Mouse Model of Intestinal Partial Obstruction

Intestinal obstructions, that impede or block peristaltic movement, can be caused by abdominal adhesions and most gastrointestinal (GI) diseases including tumorous growths. However, the cellular remodeling mechanisms involved in, and caused by, intestinal obstructions are poorly understood. Several animal models of intestinal obstructions have been developed, but the mouse model is the most cost/time effective. The mouse model uses the surgical implantation of an intestinal partial obstruction (PO) that has a high mortality rate if it is not performed correctly. In addition, mice receiving PO surgery fail to develop hypertrophy if an appropriate blockade is not used or not properly placed. Here, we describe a detailed protocol for PO surgery which produces reliable and reproducible intestinal obstructions with a very low mortality rate. This protocol utilizes a surgically placed silicone ring that surrounds the ileum which partially blocks digestive movement in the small intestine. The partial blockage makes the intestine become dilated due to the halt of digestive movement. The dilation of the intestine induces smooth muscle hypertrophy on the oral side of the ring that progressively develops over 2 weeks until it causes death. The surgical PO mouse model offers an in vivo model of hypertrophic intestinal tissue useful for studying pathological changes of intestinal cells including smooth muscle cells (SMC), interstitial cells of Cajal (ICC), PDGFR&#945;+, and neuronal cells during the development of intestinal obstruction.

Intestinal obstructions are a partial or complete blockage of the intestine that can cause severe abdominal pain, nausea, vomiting, and preventing the passage of stool. This procedure for creating intestinal partial obsructions in mice is reliable in studying the mechanisms underlying pathological cell growth and death in the intestine.

Um modelo do rato de obstrução Intestinal parcial

Intestinal obstructions, that impede or block peristaltic movement, can be caused by abdominal adhesions and most gastrointestinal (GI) diseases including ...

Modelos cirúrgicos de refluxo gastroesofágico com Ratos

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