Los autores agradecen a Christiane Pahrmann para la asistencia técnica. SS recibió fondos de la Deutsche Forschungsgemeinschaft (DFG) (SCHR992/3-2 y SCHR992/4-2).

Todo animal de trabajo debe llevarse a cabo según las directrices de cuidado de los animales pertinentes. Obtener la aprobación institucional para el trabajo con animales antes de protocolo de inicio. 1. Miointimales Hiperplasia Modelo (A) Para el modelo de hiperplasia de la íntima, la compra de C57BL/6J (Stock número 000664, C57BL/6J) ratones a la edad de 8 semanas con un peso aproximado de 25 g. Los ratones de estos experimentos en condiciones convencionales; alimentar a los ratones estándar chow ratón y proporcionar agua a voluntad. <ol><li> Preparación del ratón: Introducir el ratón a un estado de anestesia con isoflurano (2%) que utiliza una cámara de inducción. <ol><li> Quite el pelo abdominal usando un cortador de pelo, poner el ratón sobre su espalda y cubrir su nariz y boca con la máscara facial para asegurar la anestesia. </li><li> Con Provo-yodo, la desinfección de la zona abdominal universalmente, seguido de etanol 80%, en dos ciclos. </li><li> Asegurar la ausenciade los reflejos por pellizco la extremidad posterior para controlar la profundidad suficiente de la anestesia. </li><li> Separar la piel y los músculos a lo largo de la línea alba en dos pasos para destapar los órganos abdominales. </li><li> Coloque los intestinos en un guante de solución salina hidratada. Envuelva el guante alrededor de los intestinos para mantenerlos húmedos. </li><li> Atentamente limpiar el tejido graso láminas de la aorta abdominal. Exponer la aorta infrarrenal hasta su bifurcación, teniendo cuidado de no dañar ningún ramas vasculares. </li><li> En primer lugar, colocar una pinza de microcirugía en la proximal, la aorta infrarrenal para apagar el flujo de sangre. Ahora, aplique una segunda pinza distal próximo a la bifurcación aórtica. </li><li> Cuando se interrumpe el flujo de sangre, hacer una pequeña incisión en la aorta cerca de la pinza proximal. </li><li> Insertar el catéter con punta de balón, que ha sido hidratada con 0,9% de solución salina, y avanzar hacia la mordaza distal de la aorta. </li><li> Por lesión endotelial, desnudar la aorta inflando el balloon cuidadosa y lentamente tirando del catéter en la dirección de la mordaza proximal. </li><li> Repita la maniobra de la denudación dos veces. </li><li> Retire el catéter y cerrar la incisión de la aorta utilizando prolene 10-0 suturas continuas. </li><li> Abra con cuidado la pinza distal. En caso de sangrado en el sitio aortotomía, cierre la pinza de nuevo, localizar el sangrado y colocar puntos interrumpidos adicionales, según sea necesario. </li><li> Si hay sangrado se puede observar, abra lentamente la pinza proximal. </li><li> Un pulso aórtica debe ser visible distalmente desde la incisión. Ahora los intestinos se pueden arreglar de nuevo in situ. </li><li> Enjuague la cavidad abdominal utilizando solución salina estéril precalentada. </li><li> Cierre de la pared abdominal que comienza con la capa muscular utilizando 6-0 suturas de prolene en ejecución. </li><li> Siguiente adaptar la piel bajo el uso de 5-0 prolene realizar suturas continuas. </li><li> Durante el tiempo que el ratón sigue anestesiado, aplicar 4-5 mg / kg Carprofeno través de una inje subcutáneacción. </li><li> Añadir metamizol al agua de beber (50 mg Metamizol por 100 ml) para el control del dolor y continuar durante 3 días después de la cirugía. Monitorear los animales en toda la recuperación. Nota: El período de observación para este modelo es de 28 días. </li></ol></li></ol> 2. La aterosclerosis Modelo (B) Para el modelo de aterosclerosis, comprar (ApoE - / -)-E deficientes apolipoproteína ratones (Stock número 002052, B6.129P2-Apoetm1Unc / J) a una edad de 4 semanas, y luego se alimentó durante 4-6 meses. Los ratones de estos experimentos en condiciones convencionales; alimentar a los ratones una dieta alta en lípidos occidental a la llegada (Harlan Laboratorios TD.88137) y proporcionar agua ad libitum con una duración de 4 a 6 meses. <ol><li> Preparación del ratón: <ol><li> Alimentar a la ApoE - / - ratones con dieta occidental a partir de las 4 semanas de edad. La manipulación de la dieta debe comenzar directamente a la llegada. </li><li> Mantener dieta occidental a lo largo de la duración del experimento. &lt;/ Li&gt; </ol></li></ol> 3. Análisis <ol><li> Modelo de hiperplasia miointimal (A) La región de interés en este modelo es el &quot;área de la lesión&quot;. Opciones para el análisis incluyen obliteración luminal, relación I / M (relación íntima / media), grosor myointima máxima, área miointimal, tinción tricrómica para la fibrosis y tinción H &amp; E para las células mononucleares (como se ilustra en las figuras 1A-1C). De acuerdo con la pregunta científica numerosas otras tinciones como el rojo Picrosirius para el colágeno, la inmunohistoquímica, y métodos confocales se pueden aplicar. </li><li> Modelo de aterosclerosis (B) Las regiones de interés en este modelo son la válvula aórtica, arco aórtico, así como la aorta descendente. Opciones para el análisis: Sudán tinción con rojo para los lípidos y la tinción tricrómica de la válvula aórtica, arco aórtico y la aorta descendente (como se ilustra en la Figura 1D). Este modelo también produce una variedad de otras opciones de tinción comopor ejemplo Oil Red O de lípidos neutros, Picrosirius rojo, inmunohistoquímica, y métodos confocal. <ol><li> Sudán tinción con rojo: Realizar la tinción con rojo Sudán el tejido aórtico recién cosechado. <ol><li> Retire la 6h dieta antes de la cosecha. </li><li> Introducir el ratón a un estado de anestesia con isoflurano (2%) la utilización de una cámara de inducción. Asegurar la ausencia de reflejos pellizcando el miembro posterior para controlar la profundidad suficiente de la anestesia. </li><li> Abra el pecho; cortar la punta del corazón y perfundir a través del ventrículo izquierdo, primero con solución salina (3 ml), seguido de PFA al 4% (3 ml) a través de la raíz aórtica para fijar la aorta. </li><li> Libere la aorta desde la raíz hasta su bifurcación. Trate de eliminar el tejido graso tanto como sea posible. </li><li> Cortar el corazón y la raíz de la aorta, y almacenarlos en el 4% PFA para histología. </li><li> Para la histología la raíz aórtica tiene que ser colocado con cuidado en el bloque de parafina en una posición vertical para permitir el corte de la AORdiapositivas generadoras raíz de tics que muestran los 3 valvas valvulares. </li><li> Corte un extremo del árbol de la aorta y fijarlo sobre la capa de silicona con alfileres finos. Abra la aorta longitudinalmente y fijar el tejido aórtico. </li><li> Enjuague el tejido con etanol al 50%. Sumergir el tejido con una solución de tinción de Sudan III durante aproximadamente 15 min. </li><li> Enjuague ligeramente con etanol al 50% para eliminar el exceso de Sudán III. (Nota: El 50% de etanol puede lavar el tinte de distancia.) Enjuagar con dH 2 O, y tomar fotos para su posterior análisis. </li></ol></li></ol></li></ol>

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Los autores no tienen nada que revelar.

Aunque ambas enfermedades resultan en síntomas similares en el paciente, los mecanismos subyacentes de desarrollo de la placa y por lo tanto, los enfoques de tratamiento son muy diferentes 2. En diferentes formas de estenosis arterial los hallazgos clínicos en los pacientes, así como el marco de tiempo de desarrollo de la placa dependen del mecanismo subyacente. En función de los hallazgos clínicos en el paciente, diferentes métodos de análisis de la muestra deben realizars...

En los países industrializados la enfermedad isquémica del corazón sigue siendo una causa principal de mortalidad 1. Las causas de la estenosis de la arteria coronaria son múltiples e incluyen la hiperplasia miointimal así como la aterosclerosis, con la revascularización restante la estrategia de tratamiento más común 2. Modelos de investigación que distinguen claramente entre las vías mecanicistas de la hiperplasia de la íntima y la aterosclerosis son esenciales para investigar la pathobiological y los procesos fisiopatológicos en el desarrollo de la placa arterial. En este video se presentan dos modelos diferentes de ratones utilizados para estudiar bien el desarrollo de la hiperplasia miointimal o aterosclerosis. Hiperplasia miointimal se postula para formar a través del paradigma de la &quot;respuesta a la lesión&quot;, originalmente descrito para la aterosclerosis 3. La ruptura mecánica de la capa endotelial conduce a una intensa remodelación mejorada por los efectos paracrinos. Hay varios diferentes modelos animales comúnmente utilizados para estudiar la hiperplasia miointimal. Algunos grupos utilizan dispositivos metálicos en la aorta ascendente de 4 ratas. El modelo de la denudación aórtica se realiza con un catéter de balón también se usa comúnmente en ratas de laboratorio 5,6. El modelo de hiperplasia de la íntima realizado en ratones de laboratorio 7 implementa la ligadura de la arteria carótida e induce lesiones miointimales 8. En nuestro laboratorio el modelo de la denudación de la aorta abdominal - para estudiar el desarrollo de la hiperplasia miointimal - así como un modelo de reestenosis del stent humanizado 9 son de uso general. Este video hace hincapié en que la elección del modelo animal experimental apropiado es crucial para los estudios mecanicistas o fisiopatológicos de la estenosis arterial. Modelos hiperplasia miointimal deben diferenciarse de los modelos de aterosclerosis. Para estos últimos, la apolipoproteína E-deficiente (ApoE - / -) ratones en combinación con dieta occidental se utilizan comúnmente para inducir atheroscllesiones eróticos 10,11,12,13. Ejemplos para la inducción de ambos de estos tipos de enfermedad miointimal en ratones se muestran aquí, junto con diferentes opciones de modelo adaptado para analizar estenosis de los vasos 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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			<td height="17" style="height:17px;">PFA 4%</td>
			<td>Electron Microscopy Sciences</td>
			<td>#157135S</td>
			<td align="right">20%</td>
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		<tr height="17">
			<td height="17" style="height:17px;">Sudan III staining solution</td>
			<td>Sigma Aldrich</td>
			<td>S4131</td>
			<td>powder</td>
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			<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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			<td height="17" style="height:17px;">mouse ApoE-/-</td>
			<td>Jackson Laboratories</td>
			<td>&#160;Stock #002052</td>
			<td></td>
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			<td height="17" style="height:17px;">Western Diet</td>
			<td>Harlan Laboratories</td>
			<td>TD.88137</td>
			<td></td>
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			<td height="17" style="height:17px;">hair clipper</td>
			<td>WAHL</td>
			<td>8786-451A ARCO SE</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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			<td height="17" style="height:17px;">microsurgical clamp</td>
			<td>Fine Science Tools</td>
			<td>18055-04</td>
			<td>Micro-Serrefine - 4mm</td>
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			<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>
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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>
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			<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

Se han establecido varios modelos in vivo de roedores de laboratorio para la inducción de la estenosis de la arteria para imitar enfermedades que incluyen la formación de placa arterial y la estenosis, como se observa por ejemplo en la enfermedad isquémica del corazón. Dos modelos de ratón altamente reproducibles - tanto resulta en estenosis de la arteria pero cada subyacentes un camino diferente de desarrollo - se introducen aquí. Los modelos representan las dos causas más comunes de la estenosis de la arteria; a saber, se muestran un modelo de ratón para cada hiperplasia miointimal, y la aterosclerosis. Para inducir la hiperplasia miointimal, se realiza una lesión de catéter de balón de la aorta abdominal. Para el desarrollo de la placa aterosclerótica, la ApoE - se utiliza el modelo del ratón en combinación con dieta de grasos occidental - /. Diferentes opciones de modelo-adaptado para la medición y evaluación de los resultados se nombran y describen en este manuscrito. La introducción y la comparación de estos dos modelos ofrece Information para los científicos para elegir el modelo de estenosis de la arteria apropiada de acuerdo a la pregunta científica pedido.

La figura 1 muestra las diferentes opciones de análisis y el estado de la enfermedad inducida por ambos modelos. Para el modelo de hiperplasia de la íntima, se muestra el análisis de secciones transversales representativas en la tinción tricrómica. A partir de estas secciones transversales, resultados como relaciones de I / M, espesor máximo de la placa, el espesor máximo de la íntima en el lumen, la obliteración luminal en por ciento, así como área de la placa pueden ser medidos y calculados...

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 video muestra a dos modelos de desarrollo de la placa de la íntima en las arterias murinos y hace hincapié en las diferencias en la hiperplasia miointimal y la aterosclerosis.

Inducir miointimal Hiperplasia Versus aterosclerosis en ratones: una introducción de dos 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 vistas.  University Hospital Hamburg.  Este video muestra a dos modelos de desarrollo de la placa de la íntima en las arterias murinos y hace hincapié en las diferencias en la hiperplasia miointimal y la aterosclerosis. 

Video: 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.

Implantación de un manguito de la carótida para provocar esfuerzo cortante aterosclerosis inducida en ratones

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

Investigación

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 ...

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).

Mínimo procedimiento quirúrgico invasivo de inducir infarto de miocardio en ratones

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 quirúrgicos de reflujo gastroesofágico con ratones

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.

Un método mejorado para la rápida intubación de la tráquea en ratones

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

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.

Inducción de la Aterosclerosis Acelerada en Ratones: El Modelo de "Lesiones por Alambre"

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.

Lesión basada en globo para inducir la hiperplasia Myointimal de la Aorta Abdominal de ratón

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.

Inducir lesión pulmonar aguda en ratones por instilación directa de lipopolisacárido intratraal

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

A Revised Method for Inducing Secondary Lymphedema in the Hindlimb of Mice

Animal models are of paramount importance in the research of lymphedema in order to understand the pathophysiology of the disease but also to explore potential treatment options. This mouse model allows researchers to induce significant lymphedema lasting at least 8 weeks. Lymphedema is induced using a combination of fractioned radiotherapy and surgical ablation of lymphatics. This model requires that the mice get a dose of 10 Gray (Gy) radiation before and after surgery. The surgical part of the model involves ligation of three lymph vessels and extraction of two lymph nodes from the mouse hindlimb. Having access to microsurgical tools and a microscope is essential, due to the small anatomical structures of mice. The advantage of this model is that it results in statistically significant lymphedema, which provides a good basis for evaluating different treatment options. It is also a great and easily available option for microsurgical training. The limitation of this model is that the procedure can be time consuming, especially if not practiced in advance. The model results in objectively quantifiable lymphedema in mice, without causing severe morbidity and has been tested in three separate projects.

This animal model enables researchers to induce statistically significant secondary lymphedema in the hindlimb of mice, lasting at least 8 weeks. The model can be used to study the pathophysiology of lymphedema and to investigate novel treatment options.

Un método revisado para inducir el linfedema secundario en la extremidad posterior de los ratones

Animal models are of paramount importance in the research of lymphedema in order to understand the pathophysiology of the disease but also to explore ...

<meta charset="utf8"></head><body>Monitorización en tiempo real de la dinámica celular en el trasplante de pulmón de ratón

Intravital Two-Photon Microscopy of the Transplanted Mouse Lung

Complications after lung transplantation are largely related to the host immune system responding to the graft. Such immune responses are regulated by crosstalk between donor and recipient cells. A better understanding of these processes relies on the use of preclinical animal models and is aided by an ability to study intra-graft immune cell trafficking in real-time. Intravital two-photon microscopy can be used to image tissues and organs for depths up to several hundred microns with minimal photodamage, which affords a great advantage over single-photon confocal microscopy. Selective use of transgenic mice with promoter-specific fluorescent protein expression and/or adoptive transfer of fluorescent dye-labeled cells during intravital two-photon microscopy allows for the dynamic study of single cells within their physiologic environment. Our group has developed a technique to stabilize mouse lungs, which has enabled us to image cellular dynamics in na&#239;ve lungs and orthotopically transplanted pulmonary grafts. This technique allows for detailed assessment of cellular behavior within the vasculature and in the interstitium, as well as for examination of interactions between various cell populations. This procedure can be readily learned and adapted to study immune mechanisms that regulate inflammatory and tolerogenic responses after lung transplantation. It can also be expanded to the study of other pathogenic pulmonary conditions.

<meta charset="utf8"></head><body>Autor destacado: Avance de la inmunología del trasplante de pulmón a través de imágenes intravitales

Here, we present a protocol to intravitally image the transplanted mouse left lung using two-photon microscopy. This represents a valuable tool for studying cellular dynamics and interactions in real-time following murine lung transplantation.

Microscopía intravital de dos fotones del pulmón de ratón trasplantado

Complications after lung transplantation are largely related to the host immune system responding to the graft. Such immune responses are regulated by ...