The authors would like to acknowledge funding support from the University of South Florida, Department of Surgery (Mack Wu, MD, PhD).

NOTA: A aprovação para todos os procedimentos com animais apresentados a seguir foram obtidos a partir da Universidade do Comitê Animal Care do sul da Flórida (IACUC) e cumprir todas as exigências da Lei do Bem-Estar Animal e do Guia para Cuidados e Uso de Animais de Laboratório. 1. Preparação de folhas de silicone e instrumentos cirúrgicos <ol><li> Tiras pré-cortadas (10,5 cm x 3,0 cm), de não reforçado 0,01 espessura, folhas de silicone de grau médico e esterilizar utilizando uma autoclave. </li><li> Limpar e esterilizar instrumentos cirúrgicos adequados (tesouras, pinças e cortinas ou toalhas para criar um campo estéril durante a cirurgia). </li></ol> 2. Animais Experimentais <ol><li> Use adulto masculino ou ratas com peso na faixa de 250-350 g obtido a partir de um criador comercial. Se ratos idosos são utilizados, eles devem ser ≥350 g, a fim de garantir uma melhor sobrevivência pós-cirurgia. Antes do início de todas as experiências os animais aclimatizar durante, pelo menos7 dias em condições normais de um ciclo de luz-escuro de 12 horas com comida e água ad libitum. </li></ol> 3. A anestesia, analgesia pós-operatória e Preparação operativo <ol><li> Induzir a anestesia geral usando isoflurano a 3% -4% através de uma câmara de indução e manutenção (através da utilização de um cone de nariz) a 1% -2% com O2 durante a preparação da pele e cirurgia. Monitore a profundidade da anestesia pela observação do ritmo e profundidade da respiração, pitada interdigital ou palpebral reflexo de piscar. NOTA: neste momento, uma pomada veterinário pode ser colocado sobre os olhos para evitar a secura, enquanto o animal está sob anestesia. </li><li> Em uma remota localização da área cirúrgica esterilizada, coloque o rato em decúbito ventral e raspar o dorso com clippers a partir da base do pescoço para baixo cerca de 11 cm. Stencil com marcador permanente, o esboço para o 3,0 centímetros x 10,5 centímetros aba (ver Figura 1A). </li><li> Mova o rato para, um surgica designado limpol área equipada com uma almofada de aquecimento aprovado e campos cirúrgicos estéreis ou toalhas. Injetar 5 mg / kg por via subcutânea cetoprofeno antes das primeiras incisões cirúrgicas para tratamento da dor. Os fluidos adicionais (solução salina) pode ser determinado (máximo de 5 cc) por via subcutânea, conforme necessário. </li><li> Prepare a pele ainda mais limpando primeiro com 70% de álcool isopropílico e em segundo lugar com 0,2% de clorexidina, em seguida, aplicar campos estéreis para criar um campo estéril. 10% de povidona-iodo (Betadine) também pode ser usado. NOTA: Um antibiótico (ampicilina a 15 mg / kg) pode ser administrado por via subcutânea, mas, se forem utilizadas técnicas assépticas boas, não é necessário. </li></ol> 4. Criação de Feridas excisional e bipediculado Flap <ol><li> Usando um, descartável 6 milímetros ferramenta biópsia estéril, crie duas circulares feridas &quot;isquêmicos&quot; no centro da área do retalho designado (Figura 1B). A profundidade da ferida deve ser até (e não através) a fáscia do panículo Carnosus músculo (Figura 1B inserção). </li><li> Usando fórceps levantar a pele no meio do contorno da ferida criada pelo perfurador de biópsia e, em seguida, utilizar tesouras íris (com pontas curvas) para excisar a peça circular de tecidos (incluindo o músculo panniculus carnosus). O resultado será um de espessura total da ferida com a fáscia como a base da ferida. NOTA: O tecido excisado (tampões de feridas) pode ser congelado rapidamente em azoto liquido ou fixadas em 10% de formalina tamponada com O / N para processamento posterior, como controlo, a pele normal. </li><li> Criar uma aba bipediculado fazendo incisões com um bisturi estéril em cada lado das feridas isquémicas ao longo das linhas de pré-retiradas (Figura 1C) que são 10,5 centímetros de comprimento e 3,0 cm de distância. A profundidade das incisões deve ser baixo para os músculos paraspinous. Usando uma tesoura de íris, separar o fascia panniculus carnosus dos músculos paraspinous, tomando cuidado para manter a fáscia intacto como a &quot;base&quot; dos mm socos 6 (Figura 1D). </li><li> Tome uma folha de silicone pré-corte estéril e colocá-lo no meio da fáscia panniculus carnosus e os músculos paraspinous (Figura 1E), assegurando que a folha não está torto ou desistir. Usando preto, suturas não absorvíveis (tamanho 4.0) fechar as duas incisões, ancorando a folha de silicone para a pele, com pelo menos 8 interrompidos pontos de cada lado, ao longo do comprimento da aba (Figura 1F e 1G). </li><li> Utilizando uma ferramenta de punção de biópsia descartável estéril, criar duas feridas de controlo &quot;não-isquémicos&quot; internos (para baixo para a face anterior do músculo panículo carnoso) lateralmente a 1 cm dos ferimentos isquémicos em cada lado da aba (Figura 1G). </li><li> Coloque uma régua abaixo as feridas e tirar fotos digitais para fins de avaliação da ferida (ver Figura 3A). Nesta altura, o fluxo sanguíneo (perfusão) pode ser monitorizada por utilização de Doppler a laser ou outras manipulações (colocação tópica do fármaco) realizadas.</li><li> Aplique um adesivo líquido aprovado tanto cranial e caudal para as feridas e uma película transparente vestir para manter o ambiente húmido e limpo (estéril). Um curativo adicional pode ser colocado na extremidade caudal da aba para impedir que o animal de remover as suturas mais caudal. </li></ol> Procedimentos 5. pós-operatórias <ol><li> Colocar os animais em gaiolas (alojados individualmente) equipados com alimentadores rasas, de modo a impedir que o local cirúrgico de fricção contra o alimentador. Os animais não devem ser deixados sozinhos ou devolvido à companhia de outros animais, até que recupere a consciência suficiente para manter decúbito esternal e apresentam movimento proposital. Esteiras de aquecimento deve ser colocado sob a metade da gaiola para até 2 dias durante a recuperação. </li><li> Para controlar a dor no pós-operatório, administrar cetoprofeno (5 mg / kg) por via subcutânea aos animais pela manhã e 1x por dia seguinte para até 48 horas pós-cirurgia. Animais também devem ser monitorados diariamente porsinais prolongados de dor, perda de peso ou infecções de sítio cirúrgico. </li></ol> 6. Medidas feridas subsequentes e troca de curativos <ol><li> Medir feridas isquémicas e não isquémicos frequentemente sob anestesia geral usando isoflurano a 3% -4% através de uma câmara de indução e mantido (através de um cone de nariz) a 1% -2% com O 2 como no passo 3.1. </li><li> Remover o penso suavemente a não puxar o adesivo da pele. Neste momento fotos digitais adicionais sejam tomadas para medições ferida, tratamentos tópicos reaplicado, o Doppler laser (LDI) ou outras manipulações realizadas para atender às necessidades do investigador. </li><li> Aplique o adesivo e um curativo limpo e permitir que o animal possa recuperar como no passo 5.1. </li></ol> 7. Wound Recolha e eutanásia <ol><li> Isquêmica Colheita e feridas não-isquêmicas (em dias o investigador considerar apropriada), enquanto o animal está sob anestesia geral com isoflurano em 3% -4% através de uma indução câmara e mantido (através de um cone de nariz) a 1% -2% com O 2 como no passo 3.1. </li><li> Utilizando um bisturi, fazer uma excisão em forma quadrada em torno da ferida para incluir algum tecido saudável em redor da ferida. Coloque a excisão em 1,5 ml de um tubo com tampa de encaixe e encaixe de congelação em azoto líquido (armazenar a -80 ° C) para análise molecular futuro ou incubar em 10% de formalina tamponada O / N à temperatura ambiente durante o processamento histológico. NOTA: As excisões ferida também pode ser cortado pela metade para fornecer mais amostras para análise. </li><li> Após a remoção do tecido da ferida, a eutanásia do animal usando o método aprovado de inalação de CO 2. </li></ol>

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R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Altered+collagen+metabolism+and+delayed+healing+in+a+novel+model+of+ischemic+wounds.">Altered collagen metabolism and delayed healing in a novel model of ischemic wounds.</a> Wound Repair Regen. 3 (2), 204-212 (1995).</li><li>Chen, 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=Molecular+and+mechanistic+validation+of+delayed+healing+rat+wounds+as+a+model+for+human+chronic+wounds.">Molecular and mechanistic validation of delayed healing rat wounds as a model for human chronic wounds.</a> Wound Repair and Regeneration. 7, (1999).</li><li>Zhang, Q., Chang, Q., Cox, R. A., Gong, X., Gould, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyperbaric+oxygen+attenuates+apoptosis+and+decreases+inflammation+in+an+ischemic+wound+model.">Hyperbaric oxygen attenuates apoptosis and decreases inflammation in an ischemic wound model.</a> The Journal of investigative dermatology. 128 (8), 2102-2112 (2008).</li><li>Zhang, Q., Gould, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyperbaric+oxygen+reduces+matrix+metalloproteinases+in+ischemic+wounds+through+a+redox-dependent+mechanism.">Hyperbaric oxygen reduces matrix metalloproteinases in ischemic wounds through a redox-dependent mechanism.</a> The Journal of investigative dermatology. 134 (1), 237-246 (2013).</li><li>Moor, A. 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The authors have nothing to disclose.

<html> A cicatrização de feridas em ratos tem sido muitas vezes objecto de debate, devido à sua capacidade de curar feridas infectadas e alta taxa de variabilidade interanimal 5. Um dos objetivos originais do modelo durante o seu desenvolvimento foi para diminuir essa variação. Modificações na largura do retalho, reduzindo o número de feridas com posicionamento específico (centrada na aba com localização crânio-caudal consistente) e introdução de uma folha de silicone tem conseguido esse objetivo...

Desenvolvimento de medicamentos eficazes e outras terapêuticas de cura de feridas requerem adequada em modelos in vivo, apesar dos problemas conhecidos em traduzir achados em modelos animais para terapias humanas 1. O que se segue é uma descrição de um protocolo detalhado para a utilização de um modelo de rato da cicatrização de feridas isquémico para investigar os mecanismos que ainda mais a compreensão da cicatrização de feridas patológico. As espécies de rato, muitas vezes empregadas devido à sua ampla disponibilidade, tamanho e natureza dócil é usado para estudos de cicatrização de feridas, pois é grande o suficiente para fornecer uma área de pele adequada para ferir incisional e excisional, imagem e coleta de tecido 2. No entanto, deve ser tido em consideração que o cuidado da pele de um rato e um ser humano são anatomicamente diferente, com ratos a ser referido como animais de pele soltas. Esta característica distinta permite a contração da ferida, ao invés de epithelialization de contribuir significativamente para o encerramento da pele do rato wounds 2. Além disso, a presença de um músculo panículo carnoso subcutânea em ratos, contribui para a cura por ambos contracção e formação de colagénio 3,4. Estas distinções anatómicas muito importantes que foram considerados no desenvolvimento do modelo de ferida cutânea do rato isquémica e modificações específicas foram implementadas para diminuir contracção da ferida e reduzir a influência do panículo carnoso muscular 5. Em úlceras de pé diabético, úlceras venosas e úlceras de pressão, a cura é atrasada e essas feridas são consideradas crônicas. As feridas são caracterizadas pela inflamação excessiva, o que impede a ferida de progredir para as próximas fases do reparo de feridas 6. Um dos principais factores no desenvolvimento de uma ferida crónica é localizada isquemia tecidual (fluxo sanguíneo reduzido) 5 contribui para a incapacidade para limpar a inflamação. No momento em que este modelo foi sendo desenvolvida e validada (em 2003-4), Não havia modelos animais padronizados que poderiam fornecer tecido suficiente para testar a indução de angiogênese no leito da ferida, um processo importante durante a cicatrização normal e a motivação para o desenvolvimento deste modelo 5. Dito isto, o modelo aqui apresentado é uma modificação do modelo de ferimento isquémico originalmente descrito por Schwartz et ai. 7 e posteriormente utilizado na forma modificada por Chen et al. 8 No modelo de ferida isquêmica modificado, as alterações foram feitas para contornar as características anatômicas mencionadas acima do rato que levam à cura pela contração ao invés de epithelialization: (1) duas feridas por excisão de espessura total são criadas dentro de uma aba e da pele dorsal bipediculado músculo panículo carnoso é removido do leito da ferida por meio de dissecção logo acima da fáscia muscular. (2) A aba em si tem dimensões mais estreitas, garantindo que o fornecimento de sangue é aleatório e as feridas localizadas no ponto central de tele aba são isquêmicos. (3) A folha de silicone é inserida abaixo da aba, impedindo readherence e reperfusão do retalho de tecido subjacente. Contração da ferida é limitada (não eliminados), ancorando ou suturar o retalho para a folha de silicone 5. O modelo foi recentemente utilizada em estudos que vão desde efeitos oxigênio hiperbárico sobre ferida isquêmica cura 9,10 para a cicatrização de feridas isquêmica em jovem contra ratos com idade entre 11 e provou ser um modelo confiável de isquemia tecidual prolongada. As dimensões da aba bipediculado também foram adaptados para diferentes estirpes de ratos, incluindo Sprague Dawley (11 cm de comprimento por 2 cm de largura) e ratos F344 (10.5 cm por 3,0-3,5 cm de largura) e outras espécies, incluindo ratos e porcos 12 13,14. Este vídeo utiliza o F344 estirpe, ratos na manifestação do modelo de pele ferida isquêmica. Aprovação para todos os procedimentos com animais apresentados a seguir foi obtered da Universidade do Comitê Animal Care do sul da Flórida (IACUC) e cumprir todas as exigências da Lei do Bem-Estar Animal e do Guia para Cuidados e Uso de Animais de Laboratório.

<table><tbody><tr><td>Sil-Tec medical grade sheeting</td><td>Technical Products Inc.</td><td>500-3</td><td>nonreinforced, 0.01 inches in thickness</td></tr><tr><td>Mini Iris scissors, 8 cm, curved, SS</td><td>World Precision Instruments</td><td>#503671</td><td></td></tr><tr><td>Ethilon Nylon Sutures</td><td>Ethicon</td><td>1964G</td><td>black, size 4.0, PC-3 16&amp;nbsp;mm needles (3/8 circle)</td></tr><tr><td>Laser Doppler Imager</td><td>Moor Instruments</td><td>moorLDI2-IR</td><td>Standard blood flow imager: http://us.moor.co.uk/product/moorldi2-laser-doppler-imager/8</td></tr><tr><td>ImageJ</td><td>NIH</td><td>free download</td><td>http://rsb.info.nih.gov/ij/</td></tr><tr><td>Mastisol</td><td>Henry Schein</td><td>Cat # 7289210</td><td>Fisher Scientific NC9774929</td></tr><tr><td>Tegaderm</td><td>Medical Specialties&amp;nbsp;</td><td>3M1624W</td><td>Fisher Scientific NC9922128</td></tr></tbody></table>

demonstration of the rat ischemic skin wound model

A propensão para feridas crônicas em humanos aumenta com a idade, condições de doenças como diabetes e função cardiovascular prejudicada e pressão unrelieved devido à imobilidade. Os modelos animais têm sido desenvolvidos que a tentativa para imitar estas condições para o propósito de promover a compreensão da complexidade de feridas crónicas. O modelo aqui descrito é um modelo de rato de isquemia aba de pele que permite uma redução prolongada do fluxo sanguíneo resultando em feridas que se tornam isquémica e se assemelham a um fenótipo ferida crónica (vascularização reduzida, aumento de inflamação e de encerramento de feridas retardada). Ele consiste de um retalho dorsal bipediculado com 2 feridas isquêmicas colocados centralmente e 2 feridas não-isquêmicas lateral à aba como controles. Uma nova adição a este modelo isquémico aba de pele é a colocação de uma folha de silicone sob a aba que funciona como uma barreira e uma tala para prevenir e reduzir a contração revascularização como as feridas cicatrizam. Apesar dodebate de usar ratos para estudos de cicatrização de feridas devido a suas diferenças anatômicas e fisiológicas bastante distintas em comparação com os seres humanos (ou seja, a presença de um músculo panniculus carnosus, curto tempo de vida, aumento do número de folículos pilosos, e sua capacidade de curar as feridas infectadas) as modificações empregadas neste modelo o tornam uma alternativa valiosa para modelos retalhos cutâneos isquêmicos anteriormente desenvolvidos.

O protocolo de rato modelo cura isquêmico ferida deve demorar cerca de 20 min por animal se realizada de forma eficiente. Antes da aplicação de um penso, o modelo deve aparecer como representado na Figura 1G. Será importante verificar que a aba e as feridas bipediculado aí são isquémicos. Tensão de oxigénio subcutânea (PSCO 2) ao nível das feridas foi medido durante a validação deste modelo 5, colocando um eléctrodo polarográfico no tecido subcutâneo entre os dois f...

Watch this Scientific Journal Video about Demonstration of the Rat Ischemic Skin Wound Model at JoVE.com

Demonstration of the Rat Ischemic Skin Wound Model

O rato, devido ao seu tamanho, disponibilidade e de comportamento e dócil, tem sido utilizada como um modelo de pesquisa durante muitos anos. O objetivo deste protocolo é para utilizar o rato como modelo isquêmico cura de feridas cutâneas de fornecer informações valiosas sobre a fisiopatologia das feridas crônicas.

Demonstração da Wound modelo de pele de rato Isquêmico

The propensity for chronic wounds in humans increases with ageing, disease conditions such as diabetes and impaired cardiovascular function, and ...

demonstration-of-the-rat-ischemic-skin-wound-model

Universidad de Cartagena UDEC

Research

JoVE Journal

Medicine

21.2K visualizações.  University of South Florida.  O rato, devido ao seu tamanho, disponibilidade e de comportamento e dócil, tem sido utilizada como um modelo de pesquisa durante muitos anos. O objetivo deste protocolo é para utilizar o rato como modelo isquêmico cura de feridas cutâneas de fornecer informações valiosas sobre a fisiopatologia das feridas crônicas. 

Vídeo: Demonstration of the Rat Ischemic Skin Wound Model

Acute Myocardial Infarction in Rats

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular diseases. Animal models that mimic human cardiac disease, such as myocardial infarction (MI) and ischemia-reperfusion (IR) that induces heart failure as well as pressure-overload (transverse aortic constriction) that induces cardiac hypertrophy and heart failure (Goldman and Tarnavski), are useful models to study cardiovascular disease. In particular, myocardial ischemia (MI) is a leading cause for cardiovascular morbidity and mortality despite controlling certain risk factors such as arteriosclerosis and treatments via surgical intervention (Thygesen). Furthermore, an acute loss of the myocardium following myocardial ischemia (MI) results in increased loading conditions that induces ventricular remodeling of the infarcted border zone and the remote non-infarcted myocardium. Myocyte apoptosis, necrosis and the resultant increased hemodynamic load activate multiple biochemical intracellular signaling that initiates LV dilatation, hypertrophy, ventricular shape distortion, and collagen scar formation. This pathological remodeling and failure to normalize the increased wall stresses results in progressive dilatation, recruitment of the border zone myocardium into the scar, and eventually deterioration in myocardial contractile function (i.e. heart failure). The progression of LV dysfunction and heart failure in rats is similar to that observed in patients who sustain a large myocardial infarction, survive and subsequently develops heart failure (Goldman). The acute myocardial infarction (AMI) model in rats has been used to mimic human cardiovascular disease; specifically used to study cardiac signaling mechanisms associated with heart failure as well as to assess the contribution of therapeutic strategies for the treatment of heart failure. The method described in this report is the rat model of acute myocardial infarction (AMI). This model is also referred to as an acute ischemic cardiomyopathy or ischemia followed by reperfusion (IR); which is induced by an acute 30-minute period of ischemia by ligation of the left anterior descending artery (LAD) followed by reperfusion of the tissue by releasing the LAD ligation (Vasilyev and McConnell). This protocol will focus on assessment of the infarct size and the area-at-risk (AAR) by Evan's blue dye and triphenyl tetrazolium chloride (TTC) following 4-hours of reperfusion; additional comments toward the evaluation of cardiac function and remodeling by modifying the duration of reperfusion, is also presented. Overall, this AMI rat animal model is useful for studying the consequence of a myocardial infarction on cardiac pathophysiological and physiological function.

The rat model of acute myocardial infarction (AMI) is useful to study the consequence of a MI on cardiac pathophysiological and physiological function.

Infarto Agudo do Miocárdio em Ratos

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular ...

Medicina

A Simplified Technique for Producing an Ischemic Wound Model

One major obstacle in current diabetic wound research is a lack of an ischemic wound model that can be safely used in diabetic animals. Drugs that work well in non-ischemic wounds may not work in human diabetic wounds because vasculopathy is one major factor that hinders healing of these wounds. We published an article in 2007 describing a rabbit ear ischemic wound model created by a minimally invasive surgical technique. Since then, we have further simplified the procedure for easier operation. On one ear, three small skin incisions were made on the vascular pedicles, 1-2 cm from the ear base. The central artery was ligated and cut along with the nerve. The whole cranial bundle was cut and ligated, leaving only the caudal branch intact. A circumferential subcutaneous tunnel was made through the incisions, to cut subcutaneous tissues, muscles, nerves, and small vessels. The other ear was used as a non-ischemic control. Four wounds were made on the ventral side of each ear. This technique produces 4 ischemic wounds and 4 non-ischemic wounds in one animal for paired comparisons. After surgery, the ischemic ear was cool and cyanotic, and showed reduced movement and a lack of pulse in the ear artery. Skin temperature of the ischemic ear was 1-10 &deg;C lower than that on the normal ear and this difference was maintained for more than one month. Ear tissue high-energy phosphate contents were lower in the ischemic ear than the control ear. Wound healing times were longer in the ischemic ear than in the non-ischemic ear when the same treatment was used. The technique has now been used on more than 80 rabbits in which 23 were diabetic (diabetes time ranging from 2 weeks to 2 years). No single rabbit has developed any surgical complications such as bleeding, infection, or rupture in the skin incisions. The model has many advantages, such as little skin disruption, longer ischemic time, and higher success rate, when compared to many other models. It can be safely used in animals with reduced resistance, and can also be modified to meet different testing requirements.

We have developed a minimally invasive technique to create a rabbit ischemic ear wound model by dividing the central artery and nerve and the cranial neurovascular bundle. A subcutaneous tunnel then cuts all subcutaneous tissues. This procedure causes minimal skin disruption and can be safely used in diabetic animals.

Uma técnica simplificada para a produção de um modelo de ferida isquêmica

One major obstacle in current diabetic wound research is a lack of an ischemic wound model that can be safely used in diabetic animals. Drugs that work ...

Murine Model of Wound Healing

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. Impaired wound healing, which occurs in diabetic patients for example, can lead to severe unfavorable outcomes such as amputation. There is, therefore, an increasing impetus to develop novel agents that promote wound repair. The testing of these has been limited to large animal models such as swine, which are often impractical. Mice represent the ideal preclinical model, as they are economical and amenable to genetic manipulation, which allows for mechanistic investigation. However, wound healing in a mouse is fundamentally different to that of humans as it primarily occurs via contraction. Our murine model overcomes this by incorporating a splint around the wound. By splinting the wound, the repair process is then dependent on epithelialization, cellular proliferation and angiogenesis, which closely mirror the biological processes of human wound healing. Whilst requiring consistency and care, this murine model does not involve complicated surgical techniques and allows for the robust testing of promising agents that may, for example, promote angiogenesis or inhibit inflammation. Furthermore, each mouse acts as its own control as two wounds are prepared, enabling the application of both the test compound and the vehicle control on the same animal. In conclusion, we demonstrate a practical, easy-to-learn, and robust model of wound healing, which is comparable to that of humans.

A murine model of cutaneous wound healing that can be used to assess therapeutic compounds in physiological and pathophysiological settings.

Modelo Murino de Cicatrização

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. ...

In situ Transverse Rectus Abdominis Myocutaneous Flap: A Rat Model of Myocutaneous Ischemia Reperfusion Injury

Free tissue transfer is the gold standard of reconstructive surgery to repair complex defects not amenable to local options or those requiring composite tissue. Ischemia reperfusion injury (IRI) is a known cause of partial free flap failure and has no effective treatment. Establishing a laboratory model of this injury can prove costly both financially as larger mammals are conventionally used and in the expertise required by the technical difficulty of these procedures typically requires employing an experienced microsurgeon. This publication and video demonstrate the effective use of a model of IRI in rats which does not require microsurgical expertise. This procedure is an in situ model of a transverse abdominis myocutaneous (TRAM) flap where atraumatic clamps are utilized to reproduce the ischemia-reperfusion injury associated with this surgery. A laser Doppler Imaging (LDI) scanner is employed to assess flap perfusion and the image processing software, Image J to assess percentage area skin survival as a primary outcome measure of injury.

In situ Transverse Rectus Abdominis Myocutaneous Flap: A Rat Model of Myocutaneous Ischemia Reperfusion Injury

Free tissue transfer is widely employed in reconstructive surgery to restore form and function following oncological resection and trauma. Preconditioning this tissue prior to surgery may improve outcome. This article describes an in situ transverse rectus abdominis myocutaneous flap (TRAM) in rats as a means for testing preconditioning strategies.

In situ transversal reto abdominal miocutâneo: um modelo de rato de miocutâneo Isquemia Traumatismo por Reperfusão

Free tissue transfer is the gold standard of reconstructive surgery to repair complex defects not amenable to local options or those requiring composite ...

Ischemic Tissue Injury in the Dorsal Skinfold Chamber of the Mouse: A Skin Flap Model to Investigate Acute Persistent Ischemia

Despite profound expertise and advanced surgical techniques, ischemia-induced complications ranging from wound breakdown to extensive tissue necrosis are still occurring, particularly in reconstructive flap surgery. Multiple experimental flap models have been developed to analyze underlying causes and mechanisms and to investigate treatment strategies to prevent ischemic complications. The limiting factor of most models is the lacking possibility to directly and repetitively visualize microvascular architecture and hemodynamics. The goal of the protocol was to present a well-established mouse model affiliating these before mentioned lacking elements. Harder et al. have developed a model of a musculocutaneous flap with a random perfusion pattern that undergoes acute persistent ischemia and results in ~50% necrosis after 10 days if kept untreated. With the aid of intravital epi-fluorescence microscopy, this chamber model allows repetitive visualization of morphology and hemodynamics in different regions of interest over time. Associated processes such as apoptosis, inflammation, microvascular leakage and angiogenesis can be investigated and correlated to immunohistochemical and molecular protein assays. To date, the model has proven feasibility and reproducibility in several published experimental studies investigating the effect of pre-, peri- and postconditioning of ischemically challenged tissue.

The window of the murine dorsal skinfold chamber presented visualizes a zone of acute persistent ischemia of a musculocutaneous flap. Intravital epi-fluorescence microscopy permits for direct and repetitive assessment of the microvasculature and quantification of hemodynamics. Morphologic and hemodynamic results can further be correlated with histological and molecular analyses.

Lesão tecido isquêmico na Skinfold Câmara do mouse Dorsal: Um Modelo retalho de pele para investigar aguda isquemia persistente

Despite profound expertise and advanced surgical techniques, ischemia-induced complications ranging from wound breakdown to extensive tissue necrosis are ...

Assessment of Acute Wound Healing using the Dorsal Subcutaneous Polyvinyl Alcohol Sponge Implantation and Excisional Tail Skin Wound Models.

Wound healing is a complex process that requires the orderly progression of inflammation, granulation tissue formation, fibrosis, and resolution. Murine models provide valuable mechanistic insight into these processes; however, no single model fully addresses all aspects of the wound healing response. Instead, it is ideal to use multiple models to address the different aspects of wound healing. Here, two different methods that address diverse aspects of the wound healing response are described. In the first model, polyvinyl alcohol sponges are subcutaneously implanted along the mouse dorsum. Following sponge retrieval, cells can be isolated by mechanical disruption, and fluids can be extracted by centrifugation, thus allowing for a detailed characterization of cellular and cytokine responses in the acute wound environment. A limitation of this model is the inability to assess the rate of wound closure. For this, a tail skin excision model is utilized. In this model, a 10 mm x 3 mm rectangular piece of tail skin is excised along the dorsal surface, near the base of the tail. This model can be easily photographed for planimetric analysis to determine healing rates and can be excised for histological analysis. Both described methods can be utilized in genetically altered mouse strains, or in conjunction with models of comorbid conditions, such as diabetes, aging, or secondary infection, in order to elucidate wound healing mechanisms.

Here, two murine wound healing models are described, one designed to assess cellular and cytokine wound healing responses and the other to quantify the rate of wound closure. These methods can be used with complex disease models such as diabetes to determine mechanisms of various aspects of poor wound healing.

Avaliação da Cicatrização aguda de Feridas utilizando o Implante de Esponja de Álcool Subcutâneo Subcutâneo Dorsal e Modelos de Ferida de Cauda Excisional.

Wound healing is a complex process that requires the orderly progression of inflammation, granulation tissue formation, fibrosis, and resolution. Murine ...

Imunologia e Infecção

Rat Burn Model to Study Full-Thickness Cutaneous Thermal Burn and Infection

Burn induction methodologies are inconsistently described in rat models. A uniform burn wound model, which represents the clinical scenario, is necessary to perform reproducible burn research. The present protocol describes a simple and reproducible method to create ~20% total body surface area (TBSA) full-thickness burns in rats. Here, a 22.89 cm2 (5.4 cm diameter) copper rod heated at 97&#160;&#176;C in a water bath was applied to the rat skin surface to induce the burn injury. A copper rod with a high thermal conductivity was able to dissipate the heat deeper in the skin tissue to create a full-thickness burn. Histology analysis shows attenuated epidermis with coagulative damage to the full-thickness extent of the dermis and the subcutaneous tissue. Additionally, this model is representative of the clinical situations observed in hospitalized burn patients following burn injury such as immune dysregulation and bacterial infections. The model can recapitulate the systemic bacterial infection by both Gram-positive and Gram-negative bacteria. In conclusion, this paper presents an easy-to-learn and robust rat burn model that mimics the clinical situations, including immune dysregulation and bacterial infections, which is of considerable utility for the development of new topical antibiotic drugs for burn wound and infections.

A model mimicking the clinical scenario of burn injury and infection is necessary for furthering burn research. The present protocol demonstrates a simple and reproducible rat burn infection model comparable to that in humans. This facilitates the study of burn and infections following burn for developing new topical antibiotic treatments.

Modelo de queimadura de rato para estudar queimadura térmica cutânea de espessura total e infecção

Burn induction methodologies are inconsistently described in rat models. A uniform burn wound model, which represents the clinical scenario, is necessary ...

A Pre-clinical Rat Model for the Study of Ischemia-reperfusion Injury in Reconstructive Microsurgery

Ischemia-reperfusion injury is the main cause of flap failure in reconstructive microsurgery. The rat is the preferred preclinical animal model in many areas of biomedical research due to its cost-effectiveness and its translation to humans. This protocol describes a method to create a preclinical free skin flap model in rats with ischemia-reperfusion injury. The described 3 cm x 6 cm rat free skin flap model is easily obtained after the placement of several vascular ligatures and the section of the vascular pedicle. Then, 8 h after the ischemic insult and completion of the microsurgical anastomosis, the free skin flap develops the tissue damage. These ischemia-reperfusion injury-related damages can be studied in this model, making it a suitable model for evaluating therapeutic agents to address this pathophysiological process. Furthermore, two main monitoring techniques are described in the protocol for the assessment of this animal model: transit-time ultrasound technology and laser speckle contrast analysis.

Here, we describe a pre-clinical animal model for studying the pathophysiology of ischemia-reperfusion injury in reconstructive microsurgery. This free skin flap model based on the superficial caudal epigastric vessels in the rat may also allow for the evaluation of different therapies and compounds to counteract ischemia-reperfusion injury-related damage.

Um modelo pré-clínico do rato para o estudo da lesão da Isquemia-reperfusion na microcirurgia reconstrutiva

Ischemia-reperfusion injury is the main cause of flap failure in reconstructive microsurgery. The rat is the preferred preclinical animal model in many ...

Improved Rodent Model of Myocardial Ischemia and Reperfusion Injury

Myocardial ischemia and reperfusion injury (MIRI), induced by coronary heart disease (CHD), causes damage to the cardiomyocytes. Furthermore, evidence suggests that thrombolytic therapy or primary percutaneous coronary intervention (PPCI) does not prevent reperfusion injury. There is still no ideal animal model for MIRI. This study aims to improve the MIRI model in rats to make surgery easier and more feasible. A unique method for establishing MIRI is developed by using a soft tube during a key step of the ischemic period. To explore this method, thirty rats were randomly divided into three groups: sham group (n = 10); experimental model group (n = 10); and existing model group (n = 10). Findings of triphenyltetrazolium chloride staining, electrocardiography, and percent survival are compared to determine the accuracies and survival rates of the operations. Based on the study results, it has been concluded that the improved surgery method is associated with a higher survival rate, elevated ST-T segment, and larger infarct size, which is expected to mimic the pathology of MIRI better.

Myocardial ischemia-reperfusion model of rat heart is improved by using a self-made retractor, polyvinyl chloride tube, and a unique knotting method. Electrocardiogram, triphenyltetrazolium chloride and histological staining, and percent survival analysis results showed that the improved model group has higher success and survival rates than the already existing model group.

Modelo de roedor melhorado de Isquemia do Miocárdio e Lesão de Reperfusão

Myocardial ischemia and reperfusion injury (MIRI), induced by coronary heart disease (CHD), causes damage to the cardiomyocytes. Furthermore, evidence ...

A Protocol for Constructing a Rat Wound Model of Type 1 Diabetes

A single high dose of streptozotocin injection followed by full-thickness skin excision on the dorsum of rats is a common method for constructing animal models of type 1 diabetic wounds. However, improper manipulation can lead to model instability and high mortality in rats. Unfortunately, there are few existing guidelines on type 1 diabetic wound modeling, and they lack detail and do not present specific reference strategies. Therefore, this protocol details the complete procedure for constructing a type 1 diabetic wound model and analyzes the progression and angiogenic characteristics of the diabetic wounds. Type 1 diabetic wound modeling involves the following steps: preparation of the streptozotocin injection, induction of type 1 diabetes mellitus, and construction of the wound model. The wound area was measured on day 7 and day 14 after wounding, and the skin tissues of the rats were extracted for histopathological and immunofluorescence analysis. The results revealed that type 1 diabetes mellitus induced by 55 mg/kg streptozotocin was associated with lower mortality and a high success rate. The blood glucose levels were relatively stable after 5 weeks of induction. The diabetic wound healing rate was significantly lower than that of normal wounds on day 7 and day 14 (p &#60; 0.05), but both could reach more than 90% on day 14. Compared with the normal group, the epidermal layer closure of diabetic wounds on day 14 was incomplete and had delayed re-epithelialization and significantly lower angiogenesis (p &#60; 0.01). The type 1 diabetic wound model constructed based on this protocol has the characteristics of chronic wound healing, including poor closure, delayed re-epithelialization, and decreased angiogenesis compared to normal rat wounds.

The streptozotocin-induced diabetic wound model in male SD rats is currently the most widely used model for studying wound healing in type I diabetes mellitus. This protocol describes the methods used to construct this model. It also presents and addresses potential challenges and examines the progression and angiogenic characteristics of diabetic wounds.

Um Protocolo para a Construção de um Modelo de Ferida em Rato de Diabetes Tipo 1

A single high dose of streptozotocin injection followed by full-thickness skin excision on the dorsum of rats is a common method for constructing animal ...