Os autores agradecem Christiane Pahrmann para assistência técnica. SS recebeu financiamento da Deutsche Forschungsgemeinschaft (DFG) (SCHR992/3-2 e SCHR992/4-2).

Todo o trabalho animal deve ser realizada de acordo com as orientações de cuidados de animais relevantes. Obter a aprovação institucional para o trabalho de animais antes do início do protocolo. 1. Miointimais Hiperplasia Modelo (A) Para o modelo de hiperplasia da íntima, comprar C57BL/6J (da série 000.664, C57BL/6J) ratos com a idade de 8 semanas, pesando aproximadamente 25 g. Os ratos domésticos para estas experiências sob condições convencionais; alimentar de comida mouse padrão camundongos e fornecer água ad libitum. <ol><li> Rato preparação: Introduzir o mouse para um estado anestésico com isoflurano (2%), utilizando uma câmara de indução. <ol><li> Remova o cabelo abdominal usando um aparador de pêlos, coloque o rato em suas costas e cobrir o nariz ea boca com a máscara para garantir a anestesia. </li><li> Com Provo-iodo, desinfectar a zona abdominal universalmente, seguido de etanol a 80%, em dois ciclos. </li><li> Assegurar a ausênciade reflexos por beliscar o membro posterior para monitorizar a profundidade da anestesia suficiente. </li><li> Separe a pele e músculo ao longo da linha alba em duas etapas para expor os órgãos abdominais. </li><li> Coloque os intestinos em uma luva salina hidratada. Enrole a luva em torno dos intestinos para mantê-los úmidos. </li><li> Atentamente limpar o tecido adiposo sheeting da aorta abdominal. Expor a aorta infra-renal até a sua bifurcação, tomando cuidado para não ferir quaisquer embarcações filiais. </li><li> Primeiro, coloque uma braçadeira microcirúrgica no proximal, aorta infra-renal para desligar o fluxo de sangue. Agora, aplique uma segunda pinça distal próximo à bifurcação da aorta. </li><li> Quando o fluxo de sangue é interrompido, fazer uma pequena incisão na aorta perto da braçadeira proximal. </li><li> Inserção do cateter de balão, que foi hidratada com soro fisiológico 0,9%, e avançar para o grampo distal da aorta. </li><li> Por lesão endotelial, desnudar a aorta por inflar o balloon cuidadosamente e lentamente deixando o cateter na direcção da pinça proximal. </li><li> Repetir a manobra desnudação duas vezes. </li><li> Remover o cateter e fechar a incisão aórtica com prolene 10-0 suturas em execução. </li><li> Abra cuidadosamente o grampo distal. Em caso de sangramento no local da aortotomia, feche a braçadeira de novo, localizar o sangramento e colocar pontos interrompidos adicionais, conforme necessário. </li><li> Se nenhum sangramento pode ser observado, abrir lentamente a braçadeira proximal. </li><li> Um impulso da aorta deve ser visível distalmente a partir da incisão. Agora, os intestinos podem ser dispostas volta in situ. </li><li> Lavar a cavidade abdominal, utilizando solução salina estéril pré-aquecido. </li><li> Feche a parede abdominal começando com a camada muscular usando 6-0 prolene em execução. </li><li> Próxima adaptar a pele sob o uso de 5-0 prolene realizar suturas em execução. </li><li> Durante o tempo que o rato continua a ser anestesiado, aplicam-se 4-5 mg / kg através de uma inje Carprofeno subcutâneacção. </li><li> Adicionar Metamizol à água potável (50 mg por 100 ml Metamizol) para o controle da dor e continuar para a cirurgia de 3 dias após. Monitorar animal ao longo da recuperação. Nota: O período de observação para este modelo é de 28 dias. </li></ol></li></ol> 2. Modelo de Aterosclerose (B) Para o modelo de aterosclerose, comprar (ApoE - / -) E-deficiente apolipoproteína camundongos (Bolsa de número 002052, B6.129P2-Apoetm1Unc / J) em uma idade de 4 semanas, e depois alimentados por 4-6 meses. Os ratos domésticos para estas experiências sob condições convencionais; alimentar ratos dieta ocidental elevado teor de lípidos na chegada (Harlan Laboratories TD.88137) e fornecer água ad libitum durante um período de 4 a 6 meses. <ol><li> Rato preparação: <ol><li> Alimente o ApoE - / - ratos com dieta ocidental a partir das 4 semanas de idade. Manipulação dietética deve começar diretamente à chegada. </li><li> Manter dieta ocidental ao longo tempo de experiência. &lt;/ Li&gt; </ol></li></ol> 3. Análise <ol><li> Modelo de hiperplasia miointimal (A) A região de interesse neste modelo é a &quot;área da lesão.&quot; Opções para análise incluem a obliteração luminal, rácio E / M (razão íntima / média), espessura myointima máxima, área miointimal, coloração Trichrome para fibrose, e H &amp; E para a coloração de células mononucleares (tal como ilustrado nas Figuras 1A-1C). De acordo com a questão científica inúmeras outras colorações, como Picrosirius vermelho para colágeno, imunohistoquímica e métodos confocal pode ser aplicada. </li><li> Modelo de Aterosclerose (B) As regiões de interesse no modelo são a válvula aórtica, do arco aórtico, bem como a aorta descendente. Opções para análise: coloração vermelho Sudão para lipídios e tricrômico de coloração da valva aórtica, arco aórtico e aorta descendente (como ilustrado na Figura 1E). Este modelo também produz uma variedade de outras opções, como coloraçãopor exemplo Oil Red O para lipídios neutros, Picrosirius red, imunohistoquímica e métodos confocal. <ol><li> Coloração vermelho Sudão: Realizar a coloração vermelha Sudão em tecido aórtico recém-colhida. <ol><li> Retire a dieta 6h antes da colheita. </li><li> Introduzir o rato a um estado anestésico com isoflurano (2%) utilizando uma câmara de indução. Assegurar a ausência de reflexos por aperto do membro posterior para monitorizar a profundidade da anestesia suficiente. </li><li> Abra o peito; cortar o vértice do coração e perfundir através do ventrículo esquerdo, primeiro com solução salina (3 mL), seguido por 4% de PFA (3 ml) através da raiz da aorta, para fixar a aorta. </li><li> Livre a aorta da raiz até a sua bifurcação. Tentar remover o tecido adiposo, tanto quanto possível. </li><li> Corte o coração e da raiz da aorta, e armazená-los em PFA 4% para histologia. </li><li> Para a histologia da raiz da aorta tem de ser cuidadosamente colocado no bloco de parafina numa posição vertical para permitir que o corte da aortic lâminas geradoras de raiz que exibem todos os 3 folhetos valvares. </li><li> Cortar uma extremidade da árvore da aorta e corrigi-lo para a camada de silicone com pinos finos. Abra a aorta longitudinalmente e fixar o tecido aórtico. </li><li> Lavar o tecido com 50% de etanol. Mergulhe o tecido com solução corante Sudan III por cerca de 15 min. </li><li> Lavar cuidadosamente com etanol a 50% para remover o excesso de Sudan III. (Nota: 50% de etanol pode lavar o corante de distância.) Lavar com dH 2 O, e tirar fotos para análise posterior. </li></ol></li></ol></li></ol>

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Os autores não têm nada a revelar.

Embora ambas as doenças resultam em sintomas semelhantes no paciente, os mecanismos subjacentes ao desenvolvimento da placa e, portanto, as abordagens de tratamento são muito diferentes 2. Em diferentes formas de estenose arterial os achados clínicos nos pacientes, bem como o cronograma de desenvolvimento da placa depende do mecanismo subjacente. Dependendo do quadro clínico do paciente, diferentes métodos de análise da amostra devem ser realizadas 5,15. É necess...

Em nações industrializadas doença isquêmica do coração continua a ser uma das principais causas de mortalidade 1. As causas para a estenose da artéria coronária são múltiplas e incluem hiperplasia miointimal bem como aterosclerose, com revascularização restante da estratégia de tratamento mais comum 2. Modelos de pesquisa que distinguem claramente entre os caminhos mecanicistas da hiperplasia da íntima e aterosclerose são essenciais para investigar o patobiológico e processos fisiopatológicos no desenvolvimento da placa arterial. Neste vídeo de dois diferentes modelos de ratinho utilizada para estudar o desenvolvimento quer de hiperplasia miointimal ou aterosclerose são introduzidos. Hiperplasia miointimais é postulada para formar através do paradigma &quot;resposta-a-lesão&quot;, originalmente descrito para a aterosclerose 3. A ruptura mecânica da camada endotelial leva a uma remodelação intensa reforçada por efeitos parácrinos. Existem vários dimodelos animais fferent comummente usados ​​para estudar a hiperplasia miointimal. Alguns grupos de utilizar dispositivos de metal na aorta ascendente de 4 ratos. O modelo desnudamento aórtica realizada com um cateter de balão também é comumente usado em ratos de laboratório 5,6. O modelo de hiperplasia da íntima realizada em ratos de laboratório 7 implementa ligadura da artéria carótida e induz lesões miointimais 8. No nosso laboratório, o modelo de desnudação da aorta abdominal - para estudar o desenvolvimento de hiperplasia miointimal -, bem como um modelo humanizado stent 9 são vulgarmente utilizados. Este vídeo enfatiza que a escolha do modelo animal experimental adequado é crucial para estudos sobre os mecanismos fisiopatológicos ou de estenose arterial. Modelos hiperplasia miointimais deve ser diferenciado de modelos aterosclerose. Para este último, a apolipoproteína E-deficiente (ApoE - / -) ratos em combinação com uma dieta ocidental são comumente usados ​​para induzir atheroscllesões eróticos 10,11,12,13. Exemplos para a indução de ambos os tipos de doença miointimal em ratinhos são mostradas aqui, juntamente com diferentes opções de adaptação ao modelo para analisar estenose do vaso 14.

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			<td height="17" style="height:17px;width:156px;">Name</td>
			<td style="width:183px;">Company</td>
			<td style="width:139px;">Catalog number</td>
			<td style="width:140px;">Comments</td>
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			<td height="17" style="height:17px;">Thyoglycollate Broth 3%</td>
			<td>Fluka</td>
			<td align="right">70157</td>
			<td>powder</td>
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		<tr height="17">
			<td height="17" style="height:17px;">PFA 4%</td>
			<td>Electron Microscopy Sciences</td>
			<td>#157135S</td>
			<td align="right">20%</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Sudan III staining solution</td>
			<td>Sigma Aldrich</td>
			<td>S4131</td>
			<td>powder</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">mouse C57BL/6J</td>
			<td>Jackson Laboratories</td>
			<td>&#160;Stock # 0006664</td>
			<td></td>
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		<tr height="17">
			<td height="17" style="height:17px;">mouse ApoE-/-</td>
			<td>Jackson Laboratories</td>
			<td>&#160;Stock #002052</td>
			<td></td>
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		<tr height="17">
			<td height="17" style="height:17px;">Western Diet</td>
			<td>Harlan Laboratories</td>
			<td>TD.88137</td>
			<td></td>
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		<tr height="17">
			<td height="17" style="height:17px;">hair clipper</td>
			<td>WAHL</td>
			<td>8786-451A ARCO SE</td>
			<td></td>
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			<td height="17" style="height:17px;">Forene</td>
			<td>Abbott</td>
			<td></td>
			<td>Isoflurane</td>
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		<tr height="17">
			<td height="17" style="height:17px;">microsurgical clamp</td>
			<td>Fine Science Tools</td>
			<td>18055-04</td>
			<td>Micro-Serrefine - 4mm</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">clamp applicator</td>
			<td>Fine Science Tools</td>
			<td>18056-14</td>
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			<td height="17" style="height:17px;">catheter</td>
			<td></td>
			<td></td>
			<td></td>
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			<td height="17" style="height:17px;">10-0 prolene suture</td>
			<td>Ethicon</td>
			<td>788G</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">6-0 prolene suture</td>
			<td>Ethicon</td>
			<td>8709H</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">5-0 prolene suture</td>
			<td>Ethicon</td>
			<td>EH7229H</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Rimadyl</td>
			<td>Pfizer&#160;</td>
			<td></td>
			<td>Carprofen</td>
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		<tr height="17">
			<td height="17" style="height:17px;">Metacam 1.5mg/ml</td>
			<td>Boehringer Ingelheim</td>
			<td></td>
			<td>Metamizol</td>
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inducing myointimal hyperplasia versus atherosclerosis in mice: an introduction of two valid models

Vários modelos in vivo de roedores de laboratório para a indução de estenose da artéria foram estabelecidas para imitar as doenças que incluem a formação de placa arterial e estenose, como se observa, por exemplo, na doença cardíaca isquémica. Dois modelos do rato altamente reprodutíveis - ambos, resultando em estenose da artéria mas cada subjacentes um caminho diferente de desenvolvimento - são introduzidos aqui. Os modelos representam as duas causas mais comuns de estenose da artéria; ou seja, um modelo de mouse para cada hiperplasia miointimal e aterosclerose são mostrados. Para induzir hiperplasia miointimal, uma lesão por cateter balão da aorta abdominal é realizada. Para o desenvolvimento da placa aterosclerótica, a ApoE - / - modelo do rato, em combinação com dieta gordurosa ocidental é usado. Diferentes opções de adaptação do modelo para a medição e avaliação dos resultados são nomeados e descritos neste manuscrito. A introdução ea comparação destes dois modelos fornece informatíon para os cientistas a escolher o modelo de estenose da artéria apropriada de acordo com a questão científica perguntou.

A Figura 1 mostra diferentes opções de análise e o estado da doença induzida por ambos os modelos. Para o modelo de hiperplasia da íntima, a análise de secções representativas em tricromo é mostrado. A partir destas secções transversais, como resultado índices I / M, a espessura máxima da placa, da espessura máxima da íntima no lúmen, obliteração luminal em por cento, bem como a área da placa pode ser medido e calculado. Para avaliar os resultados do model...

Watch this Scientific Journal Video about Inducing Myointimal Hyperplasia Versus Atherosclerosis in Mice: An Introduction of Two Valid Models at JoVE.com

Inducing Myointimal Hyperplasia Versus Atherosclerosis in Mice: An Introduction of Two Valid Models

Este vídeo mostra dois modelos de desenvolvimento íntima placas nas artérias murino e enfatiza as diferenças de hiperplasia miointimal e aterosclerose.

Induzir miointimais Hiperplasia Versus aterosclerose em camundongos: uma introdução de dois modelos válidos

Various in vivo laboratory rodent models for the induction of artery stenosis have been established to mimic diseases that include arterial plaque ...

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12.0K visualizações.  University Hospital Hamburg.  Este vídeo mostra dois modelos de desenvolvimento íntima placas nas artérias murino e enfatiza as diferenças de hiperplasia miointimal e aterosclerose. 

Vídeo: Inducing Myointimal Hyperplasia Versus Atherosclerosis in Mice: An Introduction of Two Valid Models

Implantation of a Carotid Cuff for Triggering Shear-stress Induced Atherosclerosis in Mice

It is widely accepted that alterations in vascular shear stress trigger the expression of inflammatory genes in endothelial cells and thereby induce atherosclerosis (reviewed in 1 and 2). The role of shear stress has been extensively studied in vitro investigating the influence of flow dynamics on cultured endothelial cells 1,3,4 and in vivo in larger animals and humans 1,5,6,7,8. However, highly reproducible small animal models allowing systematic investigation of the influence of shear stress on plaque development are rare. Recently, Nam et al. 9 introduced a mouse model in which the ligation of branches of the carotid artery creates a region of low and oscillatory flow. Although this model causes endothelial dysfunction and rapid formation of atherosclerotic lesions in hyperlipidemic mice, it cannot be excluded that the observed inflammatory response is, at least in part, a consequence of endothelial and/or vessel damage due to ligation.
In order to avoid such limitations, a shear stress modifying cuff has been developed based upon calculated fluid dynamics, whose cone shaped inner lumen was selected to create defined regions of low, high and oscillatory shear stress within the common carotid artery 10. By applying this model in Apolipoprotein E (ApoE) knockout mice fed a high cholesterol western type diet, vascular lesions develop upstream and downstream from the cuff. Their phenotype is correlated with the regional flow dynamics 11 as confirmed by in vivo Magnetic Resonance Imaging (MRI) 12: Low and laminar shear stress upstream of the cuff causes the formation of extensive plaques of a more vulnerable phenotype, whereas oscillatory shear stress downstream of the cuff induces stable atherosclerotic lesions 11. In those regions of high shear stress and high laminar flow within the cuff, typically no atherosclerotic plaques are observed.
 
In conclusion, the shear stress-modifying cuff procedure is a reliable surgical approach to produce phenotypically different atherosclerotic lesions in ApoE-deficient mice.

The constricting cuff presented in this article is designed to induce atherosclerosis in the murine common carotid artery. Due to the conical shape of its inner lumen the implanted cuff generates well-defined regions of low, high and oscillatory shear stress triggering the development of atherosclerotic lesions of different inflammatory phenotypes.

Implantação de um Cuff Carotid para Triggering Shear-estresse aterosclerose induzida em camundongos

It is widely accepted that alterations in vascular shear stress trigger the expression of inflammatory genes in endothelial cells and thereby induce ...

Medicina

Quantitative Analysis and Characterization of Atherosclerotic Lesions in the Murine Aortic Sinus

Atherosclerosis is a disease of the large arteries and a major underlying cause of myocardial infarction and stroke. Several different mouse models have been developed to facilitate the study of the molecular and cellular pathophysiology of this disease. In this manuscript we describe specific techniques for the quantification and characterization of atherosclerotic lesions in the murine aortic sinus and ascending aorta. The advantage of this procedure is that it provides an accurate measurement of the cross-sectional area and total volume of the lesion, which can be used to compare atherosclerotic progression across different treatment groups. This is possible through the use of the valve leaflets as an anatomical landmark, together with careful adjustment of the sectioning angle. We also describe basic staining methods that can be used to begin to characterize atherosclerotic progression. These can be further modified to investigate antigens of specific interest to the researcher. The described techniques are generally applicable to a wide variety of existing and newly created dietary and genetically-induced models of atherogenesis.

We describe procedures to quantify and characterize atherosclerotic lesions in mouse models using precision sectioning of the aortic sinus and ascending aorta combined with histochemical and immunohistochemical analysis.

Atherosclerosis is a disease of the large arteries and a major underlying cause of myocardial infarction and stroke. Several different mouse models have ...

Acute Brain Trauma in Mice Followed By Longitudinal Two-photon Imaging

Although acute brain trauma often results from head damage in different accidents and affects a substantial fraction of the population, there is no effective treatment for it yet. Limitations of currently used animal models impede understanding of the pathology mechanism. Multiphoton microscopy allows studying cells and tissues within intact animal brains longitudinally under physiological and pathological conditions. Here, we describe two models of acute brain injury studied by means of two-photon imaging of brain cell behavior under posttraumatic conditions. A selected brain region is injured with a sharp needle to produce a trauma of a controlled width and depth in the brain parenchyma. Our method uses stereotaxic prick with a syringe needle, which can be combined with simultaneous drug application. We propose that this method can be used as an advanced tool to study cellular mechanisms of pathophysiological consequences of acute trauma in mammalian brain in vivo. In this video, we combine acute brain injury with two preparations: cranial window and skull thinning. We also discuss advantages and limitations of both preparations for multisession imaging of brain regeneration after trauma.

Acute brain trauma is a severe injury that has no adequate treatment to date. Multiphoton microscopy allows studying longitudinally the process of acute brain trauma development and probing therapeutical strategies in rodents. Two models of acute brain trauma studied with in vivo two-photon imaging of brain are demonstrated in this protocol.

Aguda Cérebro Trauma em camundongos seguiu por Longitudinal dois fótons de imagem

Although acute brain trauma often results from head damage in different accidents and affects a substantial fraction of the population, there is no ...

Minimal Invasive Surgical Procedure of Inducing Myocardial Infarction in Mice

Myocardial infarction still remains the main cause of death in western countries, despite considerable progress in the stent development area in the last decades. For clarification of the underlying mechanisms and the development of new therapeutic strategies, the availability of valid animal models are mandatory. Since we need new insights into pathomechanisms of cardiovascular diseases under in vivo conditions to combat myocardial infarction, the validity of the animal model is a crucial aspect. However, protection of animals are highly relevant in this context. Therefore, we establish a minimally invasive and simple model of myocardial infarction in mice, which assures a high reproducibility and survival rate of animals. Thus, this models fulfils the requirements of the 3R principle (Replacement, Refinement and Reduction) for animal experiments and assure the scientific information needed for further developing of therapeutical strategies for cardiovascular diseases.

A highly reproducible model for myocardial infarction in mice with minimal invasive manipulations is described. The model can be easily performed, resulting in a high reproducibility and survival rate. Thus, the described model will reduce the number of required animals as requested by the 3R principle (Replacement, Refinement and Reduction).

Minimal procedimento cirúrgico invasivo de induzir Infarto do Miocárdio em Ratos

Myocardial infarction still remains the main cause of death in western countries, despite considerable progress in the stent development area in the last ...

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.

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 ...

An Improved Method for Rapid Intubation of the Trachea in Mice

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity is a commonly used model to study both acute lung injury and fibrosis, and multiple methods have been developed for administering bleomycin (and other toxic agents) into the lungs. However, many of these approaches, such as transtracheal instillation, have inherent drawbacks, including the need for strong anesthetics and survival surgery. This paper reports a quick, reproducible method of intratracheal intubation that involves mild inhaled anesthesia, visualization of the trachea, and the use of a surrogate spirometer to confirm exposure. As a proof of concept, 8-12 week old C57BL/6 mice were administered either 2.0 U/kg of bleomycin or an equivalent volume of PBS, and both damage and fibrotic endpoints were measured post-exposure. This procedure allows researchers to treat a large cohort of mice in a relatively short period with little expense and minimal post-procedure care.

This article presents a rapid and simple method for administering bleomycin directly into the mouse trachea via intubation. Key advantages of this method are that it is highly reproducible, easy to master, and does not require specialized equipment or lengthy recovery times.

Um método melhorado para rápida de intubação da traqueia em Ratos

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity ...

Glaucoma-inducing Procedure in an In Vivo Rat Model and Whole-mount Retina Preparation

Glaucoma is a disease of the central nervous system affecting retinal ganglion cells (RGCs). RGC axons making up the optic nerve carry visual input to the brain for visual perception. Damage to RGCs and their axons leads to vision loss and/or blindness. Although the specific cause of glaucoma is unknown, the primary risk factor for the disease is an elevated intraocular pressure. Glaucoma-inducing procedures in animal models are a valuable tool to researchers studying the mechanism of RGC death. Such information can lead to the development of effective neuroprotective treatments that could aid in the prevention of vision loss. The protocol in this paper describes a method of inducing glaucoma - like conditions in an in vivo rat model where 50 &#181;l of 2 M hypertonic saline is injected into the episcleral venous plexus. Blanching of the vessels indicates successful injection. This procedure causes loss of RGCs to simulate glaucoma. One month following injection, animals are sacrificed and eyes are removed. Next, the cornea, lens, and vitreous are removed to make an eyecup. The retina is then peeled from the back of the eye and pinned onto sylgard dishes using cactus needles. At this point, neurons in the retina can be stained for analysis. Results from this lab show that approximately 25% of RGCs are lost within one month of the procedure when compared to internal controls. This procedure allows for quantitative analysis of retinal ganglion cell death in an in vivo rat glaucoma model.

Glaucoma-inducing Procedure in an In Vivo Rat Model and Whole-mount Retina Preparation

Glaucoma is characterized by damage to retinal ganglion cells. Inducing glaucoma in animal models can provide insight into the study of this disease. Here, we outline a procedure that induces loss of RGCs in an in vivo rat model and demonstrates the preparation of whole-mount retinas for analysis.

Glaucoma de indução de Procedimento em um<em&gt; In Vivo</em&gt; Modelo de Rato e Whole mount-Retina Preparação

Glaucoma is a disease of the central nervous system affecting retinal ganglion cells (RGCs). RGC axons making up the optic nerve carry visual input to the ...

Induction of Accelerated Atherosclerosis in Mice: The "Wire-Injury" Model

Atherosclerosis is a proliferative fibro-inflammatory disease developing in the arterial wall, inducing a deficient blood flow or a lack of blood flow. Moreover, by rupture of the defective vascular wall, atherosclerosis induces occlusive thrombus formation, which represents the main cause of myocardial infarction or stroke and the most frequent cause of death. Despite the advances in the cardiovascular field, many questions remain unanswered, and additional basic research is essential to improve our understanding of the molecular mechanisms during atherosclerosis and its effects. Due to limited clinical studies, there is a need for representative animal models recreating atherosclerotic conditions such as neointima formation after stent implantation, balloon angioplasty, or endarterectomy. Since the mouse presents many advantages and is the most frequently used model for studying molecular processes, the current study proposes an invasive procedure of endothelial denudation, also known as the wire-injury model, which is representative of the human condition of neointima formation in arteries after revascularization procedures.

Induction of Accelerated Atherosclerosis in Mice: The &quot;Wire-Injury&quot; Model

This study describes an invasive procedure for the induction of accelerated atherosclerosis in mice. In comparison to other methods using electric- or cryo-induced injury, mechanical-induced injury mimics the human condition of restenosis after revascularization therapies and is ideal for the study of the molecular mechanisms involved.

Indução de Aterosclerose Acelerada em Camundongos: O Modelo de "Lesão por Fio"

Atherosclerosis is a proliferative fibro-inflammatory disease developing in the arterial wall, inducing a deficient blood flow or a lack of blood flow. ...

Balloon-based Injury to Induce Myointimal Hyperplasia in the Mouse Abdominal Aorta

The use of animal models is essential for a better understanding of MH, one major cause for arterial stenosis.In this article, we demonstrate a murine balloon denudation model, which is comparable with established vessel injury models in large animals. The aorta denudation model with balloon catheters mimics the clinical setting and leads to comparable pathobiological and physiological changes. Briefly, after performing a horizontal incision in the aorta abdominalis, a balloon catheter will be inserted into the vessel, inflated, and introduced retrogradely. Inflation of the balloon will lead to intima injury and overdistension of the vessel. After removing the catheter, the aortic incision will be closed with single stiches. The model shown in this article is reproducible, easy to perform, and can be established quickly and reliably. It is especially suitable for evaluating expensive experimental therapeutic agents, which can be applied in an economical fashion. By using different knockout-mouse strains, the impact of different genes on MH development can be assessed.

This article demonstrates a murine model to study the development of myointimal hyperplasia (MH) after aortic balloon injury.

Lesão baseada no balão para induzir a hiperplasia Myointimal da Aorta Abdominal de Mouse

The use of animal models is essential for a better understanding of MH, one major cause for arterial stenosis.In this article, we demonstrate a murine ...

Inducing Acute Lung Injury in Mice by Direct Intratracheal Lipopolysaccharide Instillation

Airway administration of lipopolysaccharide (LPS) is a common way to study pulmonary inflammation and acute lung injury (ALI) in small animal models. Various approaches have been described, such as the inhalation of aerosolized LPS as well as nasal or intratracheal instillation. The presented protocol describes a detailed step-by-step procedure to induce ALI in mice by direct intratracheal LPS instillation and perform FACS analysis of blood samples, bronchoalveolar lavage (BAL) fluid, and lung tissue. After intraperitoneal sedation, the trachea is exposed and LPS is administered via a 22 G venous catheter. A robust and reproducible inflammatory reaction with leukocyte invasion, upregulation of proinflammatory cytokines, and disruption of the alveolo-capillary barrier is induced within hours to days, depending on the LPS dosage used. Collection of blood samples, BAL fluid, and lung harvesting, as well as the processing for FACS analysis, are described in detail in the protocol. Although the use of the sterile LPS is not suitable to study pharmacologic interventions in infectious diseases, the described approach offers minimal invasiveness, simple handling, and good reproducibility to answer mechanistic immunological questions. Furthermore, dose titration as well as the use of alternative LPS preparations or mouse strains allow modulation of the clinical effects, which can exhibit different degrees of ALI severity or early vs. late onset of disease symptoms.

Presented here is a step-by-step procedure to induce acute lung injury in mice by direct intratracheal lipopolysaccharide instillation and to perform FACS analysis of blood samples, bronchoalveolar lavage fluid, and lung tissue. Minimal invasiveness, simple handling, good reproducibility, and titration of disease severity are advantages of this approach.

Induzindo lesão pulmonar aguda em camundongos por instilação de lipopolissacárido intratraqueal direto

Airway administration of lipopolysaccharide (LPS) is a common way to study pulmonary inflammation and acute lung injury (ALI) in small animal models. ...