Laboratório do Dr. de CAESTECKER é suportado pelo NIH 1RO1 HL093057-01 e 1RC4DK090770-01. Laboratório Dr. Harris é suportado por DK38226, DK51265, DK62794 e financiamento da Administração de Veteranos. Suporte para rato renais cirurgias de lesões, creatinina sérica e ensaios de fibrose também fornecidos pela Vanderbilt O&#39;Brien Kidney Injury Centro concessão 1P30 DK079341.

<ol><li> Autoclave todos os instrumentos cirúrgicos antes da cirurgia. Note-se que se está realizando várias cirurgias em diferentes camundongos, lavar instrumentos após o uso e, em seguida, esterilizar utilizando um esterilizador talão quente. Não é suficiente para absorver, em etanol a 70%. </li><li> Dar origem a 0,5 ml de S / C de soro fisiológico estéril pré-operatório e pós-operatório imediato para compensar a perda de fluido do corpo durante a cirurgia. </li><li> Pesar os ratinhos. </li><li> Anestesiar mouse usando Xilazina IP / mistura de ketamina. Ele normalmente leva 3-5 minutos para os ratos para chegar a anestesia plano cirúrgico. </li><li> Raspar o local da cirurgia com a área de margem suficiente para manter o cabelo de contaminar o local da incisão. Isto precisa de ser realizado numa área de preparação, onde a cirurgia não é realizada. </li><li> Aplicar pomada lubrificante oftálmica nos olhos para evitar o ressecamento durante o procedimento. </li><li> Posicione o mouse propensos à superfície aquecida coberta com absorvente banco pad. Fita pernas para a superfície cirúrgico. </li><li> Se estiver usandoo sistema de banho de água, calor fixada em 38 ° C, 1 h antes da cirurgia. </li><li> Preparação asséptica utilizando Betadine solução escovilhão: esfregar a partir do centro do local para a periferia 3x, de cada vez, seguido por lavagem com Nolvasan para remover o Betadine. Todos Betadine deve ser removido do campo operatório antes da incisão por lavagem com Nolvasan. Antes de iniciar luvas de procedimento de assepsia deve ser alterado para ser estéril. </li><li> Cubra campo cirúrgico com uma cortina cirúrgica estéril. Isto irá evitar que o cabelo disperso de entrar no campo cirúrgico e proporcionar uma área em que para colocar os instrumentos estéreis durante a cirurgia. </li><li> Palpar localização rim através da pele. </li><li> Cortar a pele dorsal ao longo da linha média do rato (aproximadamente 1,5 cm) com uma tesoura e uma pinça. </li><li> Pele separada e subcutâneo sobre os lados dorsal direita e esquerda Através desta incisão por dissecção romba com uma tesoura e uma pinça. </li><li> Faça uma pequena incisão através da fl direitaank muscular e da fáscia acima do rim e exteriorizar o rim direito. </li><li> Dissecar cuidadosamente os pólos superior e inferior do rim livres de tecido circundante. Note-se que o tecido gordo em torno do pólo superior contém a glândula adrenal suportando o seu próprio fornecimento de sangue que pode ser empurrado para fora do rim, mas, obviamente, não devem ser removidos a partir do rato (Figura 1). Depois de rim libertadora do tecido circundante, amarre o fio de seda 4-0 ao redor do hilo do rim direito com um nó cirúrgico duplo. Deixe uma extremidade da sutura ~ 2 em tempo para manter-se o rim como você está cortando distal para o nó para que possa visualizar o local a ser cortado. Lavar o coto com solução salina estéril. </li><li> Feche a camada muscular, utilizando fio absorvível. </li><li> Adicione uma pequena incisão através do músculo flanco esquerdo e fáscia acima do rim e exteriorizar o rim esquerdo (Figura 2A). </li><li> Segure cuidadosamente renal usando uma pinça sem corte ao liberar renalpedículo de tecido adiposo ao redor usando uma pinça (Figuras 2B-2F). Demasiada pressão sobre os rins usando a pinça sem corte pode causar lesão renal assim é preciso lembrar disso quando projetar os controles de &quot;farsa&quot; para os estudos. Se você achar que seus controles sham estão desenvolvendo lesão renal (como evidenciado por um aumento na creatinina sérica), um método alternativo que você pode considerar para liberar o tecido adiposo em torno do pedículo renal é rolar suavemente os tecidos com solução salina estéril embebida de algodão cotonetes derrubado. Em nossa experiência, a gordura é muito bem ligado ao pedículo renal e não pode ser facilmente removida com cotonetes, e isso não pode ser a primeira aproximação que você gostaria de usar. No entanto, assim como outros aspectos deste modelo, isso é algo que você terá que estabelecer para si mesmo com a prática e experiência. </li><li> Grampo deixou pedículo renal com grampo vascular não traumático usando segurando uma pinça (para facilitar a colocação do grampo), use timer para diferentes clamp vezes, dependendo da estirpe do mouse e gravidade da lesão necessária (ver Tabela 1). </li><li> Cobrir o rim esquerdo com a pele (Figura 2H). </li><li> Cubra incisão na pele com gaze embebida salina. </li><li> Exteriorizar rim, confirmar aparência escura uniforme e soltar a braçadeira após os tempos indicados, e confirmar que a aparência escura inverte uniformemente em todo o rim (Figura 2I / G). Se o rim não é rápida e uniformemente re-perfundir (up-de-rosa), o mouse deve ser excluído da análise posterior. Com cuidado, empurre rim de volta para o espaço retroperitoneal. </li><li> Feche a camada muscular com fio absorvível. </li><li> Feche a camada de pele usando monofilamento de nylon sutura não absorvível. </li><li> Administrar buprenorfina analgesia. </li><li> Transferir ratos longe do campo cirúrgico para uma almofada de aquecimento até que eles acordam. </li><li> Devolver os ratos para quarto animal. </li><li> Acompanhar de perto os ratos e dar doses adicionaisde buprenorfina, como indicado acima de cada 8-12 horas, para a dor ou desconforto. Os sinais clínicos, resultando em administração de analgésicos incluem depressão ou outras alterações de comportamento, aparência anormal, ou postura como pilo-ereção, postura arqueada, a falta de higiene e alimentação, ou imobilidade. </li></ol>

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Autores não têm conflitos de interesse de divulgar.

Nós descrevemos dois modelos de IR-AKI para estudar os efeitos da lesão renal moderada e grave. Estes modelos permitem induzir lesão consistente e previsível, com baixa mortalidade. Nosso protocolo descreve muitas das dificuldades e armadilhas tradicionalmente associados com este modelo. Além disso, mostrámos que, dependendo do comprimento do pedículo clampeamento renal, o modelo induz uma ligeira e moderada LRA reversível em grande parte, ou LRA mais grave, com uma recuperação incompleta e fibrose renal persi...

A variedade de modelos experimentais de lesão renal aguda (LRA) foram desenvolvidos para atender a diversidade e complexidade da condição humana (ver referência para a recente revisão abrangente 1). Cada um desses modelos tem as suas próprias forças e fraquezas, e enquanto cada imita as condições humanas correspondentes com eficiências variadas, nenhum modelar com precisão a fisiopatologia de seus colegas humanos. Isquemia-reperfusão (IR) induzida LRA tem sido desenvolvido como um modelo de lesão renal induzida por isquemia aguda em roedores. Embora a gravidade da lesão tubular renal visto neste modelo é raramente observada em pacientes com lesões hipoperfusão renal 2, apesar de suas limitações e, em grande parte devido à natureza relativamente reprodutível deste modelo, sua ampla utilização tem proporcionado e, espera-se, continuará fornecer importantes insights sobre muitos dos mecanismos básicos comuns da AKI, reparo e terapia 3. Cirurgia IR requer familiarity com a anatomia do rim do rato, que tenham ilustrado de forma simplificada na figura 1. Lesão de isquemia-reperfusão (IR) cirurgia lesão renal pode ser realizada por meio de ventrais (laparotomia) ou dorsal abordagens (retroperitoneal). Nós usamos uma abordagem dorsal, pois é menos traumática, permitindo que o tempo de recuperação mais rápido e melhor sobrevivência (particularmente quando se aprende primeiro o procedimento). Lesão renal IR pode ser feita unilateralmente ou bilateralmente. No entanto, as diferenças entre as pressões eficazes braçadeira (que podem resultar da interposição de gordura perihilário entre as mandíbulas de aperto) e / ou diferenças nas respostas renais, a isquemia, entre os lados conduz a resultados mais variáveis. Enquanto isso não é um problema insuperável, ele pode aumentar a variabilidade entre os experimentos, que é um grande problema para este modelo. IR unilateral pode ser realizada com a nefrectomia contralateral. Este é o nosso método de escolha, uma vez que reduz a variabilidade no aperto entre pedículos e, ao mesmo tempo, umallows uma para avaliar a função renal, o que não é afectado com IR unilateral sozinho. Houve discussão sobre o que é o método mais prático vs ideal para avaliar a função renal em camundongos. Uréia (BUN) fornece uma medida da função renal e é um &quot;primeiro olhar&quot; marcador útil em alguns modelos de AKI, incluindo lesão IR. No entanto, os níveis de uréia pode ser afetada pelo estado do volume dos ratos que podem ser afetados, especialmente após abordagem ventral lesão IR, quando a recuperação tardia reduz a ingestão oral de fluidos para um número de dias pós-cirurgia. A creatinina sérica é menos influenciada pelo estado de hidratação, mas está claramente afetada pela massa muscular. Uma das dificuldades com medidas de creatinina sérica tem havido problemas com a detecção de cromógenos não de creatinina no soro de rato usando técnicas à base de ácido pícrico. Como uma alternativa, um número de centros de ter desenvolvido um método baseado em HPLC para quantificar a creatinina do rato, que não é afectado por este artefato 4. No entanto, unlike BUN e pícrico ensaios de creatinina de ácido, que requerem apenas 5-10 ul de soro, HPLC ensaios requerem ~ 25 soro uL por ensaio, a qual se for realizada em duplicado exigirá ~ 100 uL de sangue total por ensaio. Isto pode ser limitante para estudos do rato. Alguns centros têm desenvolvido métodos HPLC e Massa baseada em espectrometria mais sensíveis que permitem a análise de volumes de amostra menores, 5, 6. No entanto, estas tecnologias não são facilmente acessíveis. Um, o ensaio de cascata enzimática alternativa (que requer apenas 5-10 ul de soro) foi avaliada em ratos e amostras de soro de rato e mostrado para paralelo de perto as medições de HPLC de creatinina sérica, enquanto os testes de ácido pícrico sempre valores de creatinina sobrestimar 7. Embora este ensaio não é amplamente utilizada na literatura LRA, o ensaio é comercialmente disponível, simples de utilizar, e descobrimos dá resultados fiáveis ​​com este modelo de IR induzida LRA em ratinhos.

<table><tbody><tr><td>Ketamine (anesthetic)</td><td>Webster Veterinary</td><td>07-881-9413 (100 mg/ml)</td><td>Final concentration 30 mg/ml Ketamine with 3 mg/ml Xylazine administered at 3-4 ml/kg (100 mg/kg Ketamine and 10 mg/kg Xylazine)</td></tr><tr><td>Xylazine (analgesic)</td><td>Webster Veterinary</td><td>07-808-1939 (100 mg/ml)</td><td>As above</td></tr><tr><td>Antisedan (anti-Xylazine)</td><td>Webster Veterinary</td><td>07-867-7097 (5 mg/ml)</td><td>Optional: to reverse effects of Xylazine in order to increase the rate of recovery after surgery Use 0.5-0.7 mg/kg</td></tr><tr><td>Buprenorphine (analgesic)</td><td>Bedford Laboratories</td><td>NDC 55390-100-10 (0.3 mg/ml)</td><td>Dose 0.05-0.1 &amp;mu;g/g every 8-12 hr. Make up a 1:5 dilution in sterile normal saline preoperatively and give 2.5-5 &amp;mu;l/g of the diluted solution.</td></tr><tr><td>Ophthalmic ointment</td><td>Dechra</td><td>NDC 17033-211-38</td><td>&amp;nbsp;</td></tr><tr><td>Betadine swab sticks</td><td>Purdue Products L.P.</td><td>NDC 67618-153-01</td><td>&amp;nbsp;</td></tr><tr><td>Nolvasan Surgical Scrub</td><td>Pfizer Animal Care</td><td>300253</td><td>&amp;nbsp;</td></tr><tr><td colspan="4">&lt;strong&gt;Table 2. Drugs and solutions for I/R surgery.&lt;/strong&gt;</td></tr><tr><td>Iris Scissors</td><td>Integra Miltex</td><td>VWR 21909-404</td><td>For skin and muscle dissection</td></tr><tr><td>Curved iris forceps</td><td>FST</td><td>11065-07</td><td>To hold skin and muscle, to remove peri-nephric fat</td></tr><tr><td>Blunt forceps</td><td>ROBOZ</td><td>RS-5228</td><td>To manipulate kidneys</td></tr><tr><td>Vascular clamp (795 g pressure)</td><td>ROBOZ</td><td>RS-5459</td><td>Good for C57BL/6 and BALB/c mice strains</td></tr><tr><td>Schwartz clip applying forceps</td><td>ROBOZ</td><td>RS-5450</td><td>For RS-5459 clamps</td></tr><tr><td>Vascular clamp (75-85 g pressure)</td><td>FST</td><td>18055-02</td><td>Optimal for CD1 mice strain, but also can be used for C57BL/6 and BALB/c</td></tr><tr><td>Micro-Serrefine Clamp Applicator-14 cm with Lock</td><td>FST</td><td>18056-14</td><td>For FST 18055-02 clamps</td></tr><tr><td>Gayman T/Pump (water-bath heated platform)</td><td>Braintree Scientific</td><td>TP-650</td><td>The water heater is set at 38 &amp;deg;C 1 hr prior surgery</td></tr><tr><td>15&quot; W x 24&quot; Heated platform</td><td>Braintree Scientific</td><td>HHP-2</td><td>Connect to Gayman heated water pump</td></tr><tr><td>Heating pad</td><td>Braintree Scientific</td><td>Model 39DP</td><td>Uses microwave for heating. This is useful for warming during recovery</td></tr><tr><td>Absorbable suture (Vicryl 5-0)</td><td>ETHICON</td><td>VCP834G</td><td>For fascia and muscle</td></tr><tr><td>Non-absorbable suture: monofilament nylon MONOMID 6/0 660B)</td><td>CP Medical</td><td>CP-B660B-03</td><td>For skin</td></tr><tr><td>Halsey needle holder: Tungsten Carbide/13 cm</td><td>FST</td><td>12501-13</td><td>To hold suture needles</td></tr><tr><td>Timer</td><td>FST</td><td>06-662-3</td><td>To quantify ischemia time</td></tr><tr><td>Hot bead sterilizer</td><td>FST</td><td>18000-45</td><td>To sterilize instruments between mice if you are performing multiple surgeries (it is not sufficient to soak instruments in ethanol)</td></tr><tr><td>Electric razor</td><td>Braintree Scientific</td><td>CLP-22965</td><td>&amp;nbsp;</td></tr><tr><td>Tape</td><td>Durapore</td><td>1538-0</td><td>&amp;nbsp;</td></tr><tr><td>1 ml Syringe</td><td>EXELint</td><td>26044</td><td>&amp;nbsp;</td></tr><tr><td>Sterile cotton tipped applicators</td><td>Kendall</td><td>8884541300</td><td>&amp;nbsp;</td></tr><tr><td>Absorbent BenchPad</td><td>VWR</td><td>56617-014</td><td>&amp;nbsp;</td></tr><tr><td>Surgical drapes</td><td>VWR</td><td>21902-985</td><td>Need to be autoclaved</td></tr><tr><td>2&amp;rsquo;&amp;rsquo; x 2&amp;rsquo;&amp;rsquo; Gauze Pads</td><td>Medi-First</td><td>60673</td><td>&amp;nbsp;</td></tr><tr><td>Sterile gloves</td><td>Cardinal Health</td><td>2D7251</td><td>&amp;nbsp;</td></tr><tr><td colspan="4">&lt;strong&gt;Table 3. Equipment and instruments for I/R surgery.&lt;/strong&gt;</td></tr></tbody></table>

ischemia-reperfusion model of acute kidney injury and post injury fibrosis in mice

Isquemia-reperfusão induzida lesão renal aguda (IR-AKI) é amplamente utilizado como um modelo de LRA em camundongos, mas os resultados são muitas vezes bastante variável, com altas taxas de mortalidade muitas vezes não declarada que pode confundir análises. Bilateral pedículo clampeamento renal é comumente usado para induzir o IR-AKI, mas as diferenças entre as pressões de fixação eficazes e / ou respostas renais à isquemia entre os rins muitas vezes levam a resultados mais variáveis. Além disso, os tempos mais curtos da braçadeira são conhecidas por induzir a lesão tubular mais variável, e quando os ratos submetidos a lesão bilateral com tempos mais longos da braçadeira desenvolver lesão tubular mais consistente, eles morrem frequentemente durante os primeiros 3 dias após a lesão devido a insuficiência renal grave. Para melhorar a sobrevivência pós-lesão e obter resultados mais consistentes e previsíveis, desenvolvemos dois modelos de lesão unilateral de isquemia-reperfusão, seguido por nefrectomia contralateral. Ambas as cirurgias são realizadas através de uma abordagem dorsal, reduzindo o stress cirúrgico resultando from laparotomia ventral, comumente usado para rato IR-AKI cirurgias. Para a indução da lesão ratinhos BALB / c moderadas submeter unilateral de aperto do pedículo renal durante 26 min, e também submetidos a nefrectomia contralateral simultâneo. Utilizando esta abordagem, 50-60% dos ratinhos desenvolvem moderada LRA 24 h depois da lesão, mas 90-100% dos ratinhos sobreviver. Para induzir o LRA mais grave, ratinhos BALB / c sofrem pedículo renal aperto durante 30 min seguido por nefrectomia contralateral 8 dias após o ferimento. Isto permite a avaliação funcional da recuperação renal após lesão com 90-100% de sobrevivência. Cedo dano tubular pós-lesão, bem como a fibrose pós lesão são altamente consistente com esse modelo.

Moderado IR induzida AKI. IR Unilateral com nefrectomia contralateral simultânea reduz substancialmente a variabilidade nos resultados, mas com tempos mais curtos de fixação necessários para os ratos para sobreviver a este procedimento, ainda constatou que apenas 50-60% dos camundongos desenvolveu o esperado insuficiência renal 24 hr após a lesão (Figura 3A). Em termos práticos, isso cria dificuldades avaliação dos dados, a menos que os estudos envolvem esquemas de tratamento ...

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Ischemia-reperfusion Model of Acute Kidney Injury and Post Injury Fibrosis in Mice

Descrevemos modelos de lesão renal por isquemia e reperfusão induzida moderada e grave em que os ratos submetidos a clampeamento do pedículo renal unilateral seguido de nefrectomia contralateral simultânea ou tardia, respectivamente. Estes modelos consistentemente dar origem a uma disfunção renal e fibrose pós-lesão, mas a gravidade da lesão e sobrevivência dependem de fundo, idade e equipamento cirúrgico mouse.

Isquemia-reperfusão modelo de lesão renal aguda e Pós Lesão fibrose em camundongos

Ischemia-reperfusion induced acute kidney injury (IR-AKI) is widely used as a model of AKI in mice, but results are often quite variable with high, often ...

ischemia-reperfusion-model-acute-kidney-injury-post-injury-fibrosis

Research

JoVE Journal

Medicine

39.5K visualizações.  Vanderbilt University Medical Center. Descrevemos modelos de lesão renal por isquemia e reperfusão induzida moderada e grave em que os ratos submetidos a clampeamento do pedículo renal unilateral seguido de nefrectomia contralateral simultânea ou tardia, respectivamente. Estes modelos consistentemente dar origem a uma disfunção renal e fibrose pós-lesão, mas a gravidade da lesão e sobrevivência dependem de fundo, idade e equipamento cirúrgico mouse.

Vídeo: Ischemia-reperfusion Model of Acute Kidney Injury and Post Injury Fibrosis in Mice

Normothermic Cardiac Arrest and Cardiopulmonary Resuscitation: A Mouse Model of Ischemia-Reperfusion Injury

Acute Kidney Injury (AKI) is a common, highly lethal, complication of critical illness which has a high mortality1-4 and which is most 
frequently caused by whole-body hypoperfusion.5,6 Successful reproduction of whole-body hypoperfusion in rodent models has been fraught with 
difficulty.7-9,9,10 Models which employ focal ischemia have repeatedly demonstrated results which do not translate to the clinical setting, and larger 
animal models which allow for whole body hypoperfusion lack access to the full toolset of genetic manipulation possible in the mouse.11,12 However, in recent 
years a mouse model of cardiac arrest and cardiopulmonary resuscitation has emerged which can be adapted to model AKI.13 This model reliably reproduces 
physiologic, functional, anatomic, and histologic outcomes seen in clinical AKI, is rapidly repeatable, and offers all of the significant advantages of a murine surgical 
model, including access to genetic manipulative techniques, low cost relative to large animals, and ease of use. Our group has developed extensive experience 
with use of this model to assess a number of organ-specific outcomes in AKI.14,15

A powerful model for perioperative and critical care related acute kidney injury is presented. Using whole body hypoperfusion induced by cardiac arrest it is possible to nearly replicate the histologic and functional changes of clinical AKI.

Cardiac Arrest normotérmica e Ressuscitação Cardiopulmonar: um modelo do rato de isquemia-reperfusão

Acute Kidney Injury (AKI) is a common, highly lethal, complication of critical illness which has a high mortality1-4 and which is most 
frequently caused ...

Medicina

Renal Ischaemia Reperfusion Injury: A Mouse Model of Injury and Regeneration

Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI) in patients and occlusion of renal blood flow is unavoidable during renal transplantation. Experimental models that accurately and reproducibly recapitulate renal IRI are crucial in dissecting the pathophysiology of AKI and the development of novel therapeutic agents. Presented here is a mouse model of renal IRI that results in reproducible AKI. This is achieved by a midline laparotomy approach for the surgery with one incision allowing both a right nephrectomy that provides control tissue and clamping of the left renal pedicle to induce ischaemia of the left kidney. By careful monitoring of the clamp position and body temperature during the period of ischaemia this model achieves reproducible functional and structural injury. Mice sacrificed 24 hr&#160;following surgery demonstrate loss of renal function with elevation of the serum or plasma creatinine level as well as structural kidney damage with acute tubular necrosis evident. Renal function improves and the acute tissue injury resolves during the course of 7 days following renal IRI such that this model may be used to study renal regeneration. This model of renal IRI has been utilized to study the molecular and cellular pathophysiology of AKI as well as analysis of the subsequent renal regeneration.

The mouse model of renal ischaemia reperfusion injury described here comprises of a right nephrectomy that provides control tissue and clamping of the left renal pedicle to induce ischaemia that results in acute kidney injury. This model uses a midline laparotomy approach with all steps performed via one incision.

Renal Isquemia Reperfusão: um modelo do rato de lesão e regeneração

Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI) in patients and occlusion of renal blood flow is unavoidable ...

Induction and Assessment of Ischemia-reperfusion Injury in Langendorff-perfused Rat Hearts

The biochemical events surrounding ischemia reperfusion injury in the acute setting are of great importance to furthering novel treatment options for myocardial infarction and cardiac complications of thoracic surgery. The ability of certain drugs to precondition the myocardium against ischemia reperfusion injury has led to multiple clinical trials, with little success. The isolated heart model allows acute observation of the functional effects of ischemia reperfusion injury in real time, including the effects of various pharmacological interventions administered at any time-point before or within the ischemia-reperfusion injury window. Since brief periods of ischemia can precondition the heart against ischemic injury, in situ aortic cannulation is performed to allow for functional assessment of non-preconditioned myocardium. A saline filled balloon is placed into the left ventricle to allow for real-time measurement of pressure generation. Ischemic injury is simulated by the cessation of perfusion buffer flow, followed by reperfusion. The duration of both ischemia and reperfusion can be modulated to examine biochemical events at any given time-point. Although the Langendorff isolated heart model does not allow for the consideration of systemic events affecting ischemia and reperfusion, it is an excellent model for the examination of acute functional and biochemical events within the window of ischemia reperfusion injury as well as the effect of pharmacological intervention on cardiac pre- and postconditioning. The goal of this protocol is to demonstrate how to perform in situ aortic cannulation and heart excision followed by ischemia/reperfusion injury in the Langendorff model.

The isolated rat heart is an enduring model for ischemia reperfusion injury. Here, we describe the process of harvesting the beating heart from a rat via in situ aortic cannulation, Langendorff perfusion of the heart, simulated ischemia-reperfusion injury, and infarct staining to confirm the extent of ischemic insult.

Indução e Avaliação de isquemia-reperfusão em Langendorff-perfundidos Rato Corações

The biochemical events surrounding ischemia reperfusion injury in the acute setting are of great importance to furthering novel treatment options for ...

Murine Model of Intestinal Ischemia-reperfusion Injury

Intestinal ischemia is a life-threatening condition associated with a broad range of clinical conditions including atherosclerosis, thrombosis, hypotension, necrotizing enterocolitis, bowel transplantation, trauma and chronic inflammation. Intestinal ischemia-reperfusion (IR) injury is a consequence of acute mesenteric ischemia, caused by inadequate blood flow through the mesenteric vessels, resulting in intestinal damage. Reperfusion following ischemia can further exacerbate damage of the intestine. The mechanisms of IR injury are complex and poorly understood. Therefore, experimental small animal models are critical for understanding the pathophysiology of IR injury and the development of novel therapies.
Here we describe a mouse model of acute intestinal IR injury that provides reproducible injury of the small intestine without mortality. This is achieved by inducing ischemia in the region of the distal ileum by temporally occluding the peripheral and terminal collateral branches of the superior mesenteric artery for 60 min using microvascular clips. Reperfusion for 1 hr, or 2 hr after injury results in reproducible injury of the intestine examined by histological analysis. Proper position of the microvascular clips is critical for the procedure. Therefore the video clip provides a detailed visual step-by-step description of this technique. This model of intestinal IR injury can be utilized to study the cellular and molecular mechanisms of injury and regeneration.

Here we describe the detailed procedure of intestinal ischemia-reperfusion in mice which results in reproducible injury without mortality to encourage the standardization of this technique across the field. This model of intestinal ischemia-reperfusion injury can be utilized to study the cellular and molecular mechanisms of injury and regeneration.

Modelo murino de isquemia-reperfusão

Intestinal ischemia is a life-threatening condition associated with a broad range of clinical conditions including atherosclerosis, thrombosis, ...

Evaluation of Coronary Flow Reserve After Myocardial Ischemia Reperfusion in Rats

Coronary artery disease is the leading cause of death worldwide. After an acute myocardial infarction, early and successful myocardial intervention via recanalization of the coronary artery is the most effective strategy for reducing the size of ischemic myocardium. The coronary microvasculature cannot be visualized and imaged&#160;in vivo, but there are several invasive and noninvasive techniques that can be used to assess parameters which depend directly on coronary microvascular function. The endothelial function after ischemia reperfusion can be assessed also at the level of the coronary circulation via the coronary flow reserve (CFR).&#160;In this study, peak velocity of left anterior descending (LAD) coronary arteries was measured in rats in vivo via Transthoracic Doppler Echocardiography during resting and stress challenge (induced by Dobutamine). A normal heart can increase its coronary blood flow up to four times above the resting values during stress induction. Following ischemia reperfusion, we found a significantly diminished CFR, which can be used as a marker of coronary microvascular dysfunction. CFR has opened a window on the importance of microvascular dysfunction and has been shown to predict cardiovascular risk independent of whether the severe obstructive disease is present.

Coronary flow reserve (CFR), is defined as the ratio of maximal coronary blood flow to the resting coronary blood flow. We present a protocol for evaluating CFR in rats via ultrasound, which offers the opportunity to predict cardiovascular risk factors in the absence of obstructive coronary disease.

Avaliação da reserva de fluxo coronariano após reperfusão de isquemia miocárdica em ratos

Coronary artery disease is the leading cause of death worldwide. After an acute myocardial infarction, early and successful myocardial intervention via ...

An Effective Mouse Model of Unilateral Renal Ischemia-Reperfusion Injury

Ischemia-reperfusion injury (IRI) is the leading cause of acute renal failure and is a significant contributor to delayed graft function. Animal models are the only available resources that mimic the complexities of the IRI-associated damage encountered in vivo. This paper describes an effective mouse model of unilateral renal IRI that delivers highly reproducible data. Ischemia is induced by occluding the right renal pedicle for 30 min followed by reperfusion. In addition to the surgical procedure, a sequential overview of the expected physiological and histopathological changes following renal IRI will be provided by comparing data from seven different reperfusion times (4 h, 8 h, 16 h, 1 day, 2 days, 4 days, and 7 days). Critical data for planning experiments ahead, such as mean surgical time, average anesthetic consumption, and body weight changes over time, will be shared. This work will help researchers implement a reliable renal IRI model and select the appropriate reperfusion time that aligns with their intended investigative goals.

Renal ischemia-reperfusion injury is associated with high morbidity and mortality in hospitalized patients. Here, we present a simple and effective mouse model of unilateral renal ischemia-reperfusion injury and provide a sequential overview of representative pathological changes observed in the kidney.

Um modelo eficaz de rato de isquemia renal unilateral-reperfusão lesão

Ischemia-reperfusion injury (IRI) is the leading cause of acute renal failure and is a significant contributor to delayed graft function. Animal models ...

The Mouse Isolated Perfused Kidney Technique

The mouse isolated perfused kidney (MIPK) is a technique for keeping a mouse kidney under ex vivo conditions perfused and functional for 1 hr. This is a prerequisite for studying the physiology of the isolated organ and for many innovative applications that may be possible in the future, including perfusion decellularization for kidney bioengineering or the administration of anti-rejection or genome-editing drugs in high doses to prime the kidney for transplantation. During the time of the perfusion, the kidney can be manipulated, renal function can be assessed, and various pharmaceuticals administered. After the procedure, the kidney can be transplanted or processed for molecular biology, biochemical analysis, or microscopy.
This paper describes the perfusate and the surgical technique needed for the ex vivo perfusion of mouse kidneys. Details of the perfusion apparatus are given and data are presented showing the viability of the kidney&#39;s preparation: renal blood flow, vascular resistance, and urine data as functional, transmission electron micrographs of different nephron segments as morphological readouts, and western blots of transport proteins of different nephron segments as molecular readout.

The mouse isolated perfused kidney (MIPK) is a technique for keeping a mouse kidney under ex vivo conditions perfused and functional for 1 hr. The buffers and surgical technique are described in detail.

A técnica de rim perfundidos rato isolado

The mouse isolated perfused kidney (MIPK) is a technique for keeping a mouse kidney under ex vivo conditions perfused and functional for 1 hr. This is a ...

Biologia

Technical Refinement of a Bilateral Renal Ischemia-Reperfusion Mouse Model for Acute Kidney Injury Research

Cardiac arrest poses a large public health burden. Acute kidney injury (AKI) is an adverse marker in survivors of cardiac arrest following the return of spontaneous circulation (ROSC) after successful cardiopulmonary resuscitation. Conversely, recovery of kidney function from AKI is a predictor of favorable neurological outcomes and hospital discharge. However, an effective intervention to prevent kidney damage caused by cardiac arrest after ROSC is lacking, suggesting that additional therapeutic strategies are required. Renal hypoperfusion and reperfusion are two pathophysiological mechanisms that cause AKI after cardiac arrest. Animal models of ischemia-reperfusion-induced AKI (IR-AKI) of both kidneys are comparable with patients with AKI following ROSC in a clinical setting. However, IR-AKI of both kidneys is technically challenging to analyze because the model is associated with high mortality and wide variation in kidney damage, which may affect the analysis. Lightweight mice were chosen, placed under general anesthesia with isoflurane, subjected to surgery with a dorsolateral approach, and their body temperature maintained during operation, thereby reducing tissue damage and establishing a reproducible acute renal IR-AKI research protocol.

This study established a protocol focusing on the technical refinement of a mouse model of bilateral renal ischemia-reperfusion for acute kidney injury research.

Refinamento Técnico de um Modelo Bilateral de Isquemia-Reperfusão Renal em Camundongos para Pesquisa de Lesão Renal Aguda

Cardiac arrest poses a large public health burden. Acute kidney injury (AKI) is an adverse marker in survivors of cardiac arrest following the return of ...

Developing Murine Acute Kidney Injury Model Using Bilateral Ischemia-Reperfusion

Bilateral Renal Ischemia-Reperfusion Model for Acute Kidney Injury in Mice

Acute kidney injury (AKI) is defined as a rapid decline in renal function, in which persistent kidney dysfunction gradually progresses to chronic kidney disease (CKD) due to the irreversible loss of nephrons and their maladaptive repair. In recent years, the incidence of AKI has been increasing concerning diverse etiologies, including volume depletion, sepsis, nephrotoxicity, muscle injury, and major trauma, in which ischemia-reperfusion injury (IRI)&#160;accounts for most episodes. Development of the IRI model in mice is induced by surgical clamping of the renal pedicles, which provides powerful and controllable tools for preclinical models of AKI. Importantly, the IRI model is deployed at different stages of the AKI development, especially in the processes of AKI to CKD. Despite the IRI model being widely practiced in many laboratories, a series of variables still influence the results of this model. Here, we describe the procedure of IRI model development to provide a repeatable and reliable method for researchers to explore the underlying pathogenesis in the development of AKI and the progression of AKI to CKD.

The ischemia-reperfusion injury (IRI) model can be used at different stages of acute kidney injury (AKI) development, especially during AKI to chronic kidney disease (CKD) progression. Here, we describe the procedure for IRI model development in mice via a trans-abdominal approach, clamping renal pedicles via a vascular clip to induce ischemic injury.

Acute kidney injury (AKI) is defined as a rapid decline in renal function, in which persistent kidney dysfunction gradually progresses to chronic kidney ...

Unilateral Ureteral Obstruction Model for Investigating Kidney Interstitial Fibrosis

Kidney fibrosis is the final pathological outcome of progressive chronic kidney disease (CKD). The unilateral ureteral obstruction (UUO) model is widely used to elucidate the molecular and cellular mechanisms underlying kidney interstitial fibrosis and to identify potential therapeutic targets. This model is established in mice through surgical ligation of a unilateral ureter, a procedure that is relatively straightforward and easy to perform. However, the UUO mouse model is known to exhibit significant variability and inconsistency, influenced by factors such as mouse strain, age, sex, anesthesia type, duration of surgery, body temperature during the procedure, the operator's surgical skills, feeding conditions, and the overall health status of the mice. Variations in surgical techniques, suture placement, and the duration of obstruction contribute to the variability in outcomes. Additionally, inconsistent sampling of obstructed kidneys further increases variability in the assessment of kidney fibrosis. This study outlines the process of developing the UUO mouse model and evaluating interstitial fibrosis, discusses the technical challenges contributing to the model's unpredictability, and proposes potential solutions. These insights aim to establish a more standardized and universally applicable approach for investigating kidney fibrosis.

This protocol describes a method for inducing unilateral ureteral obstruction (UUO) in mice to study the progression of tissue fibrosis in obstructive nephropathy. It includes surgical procedures, post-operative care, and methods for fibrosis assessment.

Kidney fibrosis is the final pathological outcome of progressive chronic kidney disease (CKD). The unilateral ureteral obstruction (UUO) model is widely ...