Name: a murine model of arterial restenosis: technical aspects of femoral wire injury
Uploaded: 2015-03-10T15:00:00.000+00:00
Duration: 6 min 42 s
Description: Watch this Scientific Journal Video about A Murine Model of Arterial Restenosis: Technical Aspects of Femoral Wire Injury at JoVE.com

This work was supported by a Wisconsin Partnership Program New Investigator Award (ID 2832), a National Heart, Lung, Blood Institute R01 Grant (HL-068673) and a T32 training Grant (HL-110853). We thank Dr. Melina Kibbe&#8217;s group at Northwestern University for providing helpful information.

Declaración de Ética: NOTA: Todos los procedimientos se ajustan a la Guía para el Cuidado y Uso de Animales de Laboratorio (National Academies Press, 8ª edición, 2011), y los protocolos aprobados por el Comité de Cuidado y Uso de Animales Institucional de la Universidad de Wisconsin. Todas las cirugías se realizaron bajo anestesia con isoflurano (a través de la inhalación, caudal de 2 ml / min), y se hicieron todos los esfuerzos para minimizar el sufrimiento. Los animales fueron sacrificados en una cámara llena gradualmente con CO 2. 1. La inducción de la anestesia general y la incisión de la piel <ol><li> Utilice macho C57BL / 6 ratones con una edad de 12-16 semanas y el peso de 23-28 g. Anestesiar al animal mediante isoflurano a través de un aparato de anestesia de circuito cerrado. Confirmar anestesia adecuada apretando su dedo del pie. Aplique un poco de ungüento de lágrimas artificiales en los ojos para evitar la sequedad. </li><li> Coloque el ratón en una posición supina con la extremidad posterior izquierda ligeramente secuestrado y la articulación de la rodilla slightly flexionada. Afeitarse el pelo alrededor de la región superior del muslo izquierdo y desinfectar la piel con clorhexidina, aplicado tres veces con algodón estéril aplicadores con punta. Utilice un esterilizador de cuentas caliente para mantener los instrumentos esterilizados durante la cirugía. </li><li> Coloque un paño de gasa esterilizada sobre la pierna izquierda. Hacer una incisión longitudinal en la piel 1,5 cm recta en el muslo medial izquierdo de la articulación de la rodilla hasta la ingle (Figura 1A). </li></ol> 2. La exposición de la arteria femoral y Ramas NOTA: La Figura 1B muestra la anatomía vascular grave en la parte superior del muslo. La arteria femoral superficial (SFA) se puede observar a través de un microscopio de disección cuando la incisión de la piel se hace adecuadamente a lo largo de la línea media del muslo medial. <ol><li> Abre la fascia delgada que recubre el SFA con finas pinzas y luego bucle del SFA con 9-0 sutura de nylon. NOTA: En este proceso, el nervio femoral es fácil de poner comoide, pero la vena femoral adyacente requiere mucha atención, porque su pared es tan delgada que perfora y sangra fácilmente. La técnica clave es centrarse en la propia arteria; siempre que la disección se lleva a cabo cerca de la arteria, cualquier daño accidental vena es evitable. </li><li> Una vez que la SFA se enlaza, mantenga la sutura con una pinza de mosquito y tire de él ligeramente hacia abajo. Esta maniobra hace más disección más fácil, pero para evitar daños en la arteria no tire con demasiada fuerza. </li><li> Continuar la disección de la arteria proximal para exponer y bucle de la arteria femoral común (CFA) con 9-0 sutura de nylon. NOTA: Por lo general, rizando el Comité de Libertad Sindical en un punto distal a la arteria epigástrica (Figura 1B) es suficiente para la inserción de cables. Mantenga el lazo de sutura CFA con pinzas de mosquitos de la misma manera. </li><li> Tire del lazo de sutura CFA hacia arriba y el lazo de sutura SFA hacia abajo para destapar la bifurcación de SFA y la arteria femoral profunda (DFA). La DFA, la rama principal del Comité de Libertad Sindical,va hacia el músculo del muslo (Figura 1B). NOTA: El cable se inserta desde la DFA después. </li><li> Pase el DFA con mucha precaución debido a que la vena adyacente está enredado por debajo de la arteria. En caso de sangrado de la vena, un 30 a 60 seg compresión simple con una gasa es generalmente suficiente para producir hemostasis. </li><li> Una vez que el DFA se enlaza con 9-0 sutura de nylon, asegúrese de que los tres bucles de sutura están en sus posiciones correctas (Figura 2A). </li><li> Proceder con la disección de la DFA distalmente para ligar la arteria en un punto lo más lejos posible de la bifurcación. Cortar sutura extra, pero dejar una cierta longitud de manera que los dos extremos se pueden celebrar con pinzas de mosquito, que estabilizan la DFA hacer la inserción de cables más fácil. </li></ol> 3. Creación de Lesión alambre <ol><li> Inserte el cable a través de DFA <ol><li> Colar las suturas CFA, SFA, y DFA para establecer una pinza hemostática temporal. </li><li> Haz un pequeño agujero en el DFA con microtijeras. Insertar las puntas de los micropinzas curvadas para dilatar el agujero suficientemente grande para un alambre con un diámetro de 0,015 pulgadas (Figura 2B demuestra la diferencia de tamaño entre la arteria y el cable). <ol><li> Antes de hacer un agujero en la DFA, aflojar el lazo de sutura CFA y suavemente sujetar / apriete el DFA varias veces con micropinzas-opacos punta. Esta maniobra se amplía el diámetro arterial notablemente para facilitar la inserción de cables. Humedecer el alambre a fondo con PBS también es importante para una inserción suave. </li><li> Al hacer un agujero en la DFA, no recortar la pared arterial, pero hacer un pequeño pellizco en forma de V y pellizcar la solapa con micropinzas de punta afilada para la manipulación. </li></ol></li><li> Inserte el cable por el agujero adecuadamente dilatado en la DFA. Avanzar suavemente el alambre hacia la arteria ilíaca mientras afloja el lazo de sutura alrededor del CFA. 5-8 mm es suficiente para cubrir toda la longitud CFA en la mayoría de los casos (Figura 2C </strong&gt;). No inserte el cable de fuerza como una perforación arterial por lo general resulta en la pérdida del ratón. Acortar el cable a aproximadamente 15 mm de longitud ayuda a la manipulación. </li></ol></li><li> Deja alambre dentro de 1 Min <ol><li> Después de insertar el cable a la longitud óptima, se deja durante 1 min a estirar demasiado la pared arterial. Humedezca el alambre y las arterias con PBS para evitar que se seque. Otra sutura de nylon 9-0 se puede colocar alrededor de la DFA proximal al punto de inserción de alambre durante este tiempo de espera. Esta sutura se utilizará más adelante para cerrar el orificio de la DFA después de la extracción del alambre. </li></ol></li><li> Recuperar alambre y reanudar el flujo sanguíneo <ol><li> Sujete el cable con pinzas de canulación del vaso, y tirar de ella con suavidad; el cable debe ser recuperada sin problemas. Para superar cualquier resistencia, causada generalmente por la adhesión del alambre a la pared arterial, retroceso del cable con rotación suave es útil. Una vez más, una maniobra contundente podría resultar en la pérdida de los animales. </li><li> Laespués de recuperar el cable, ligar la DFA en el punto de bifurcación con sutura de nylon 9-0. No ligar demasiado cerca de la bifurcación, que pondría en peligro el flujo de salida de sangre a la SFA. </li><li> Aflojar los lazos de sutura SFA y CFA para reanudar el flujo de sangre normal. Tenga en cuenta que el Comité de Libertad Sindical es bien expandimos la inserción del cable (Figura 2D). </li></ol></li></ol> 4. Cierre de la piel y Cuidado Postoperatorio <ol><li> Sangra de control. Exudación Minor puede ser detenida por compresión simple; algunos importantes hemorragias arteriales requieren puntos de sutura con una sutura de nylon 11-0. Estas arterias suturadas eventualmente resultarán en la oclusión arterial. </li><li> Cierre de la piel de la herida con grapadoras de piel (generalmente 3-4 grapas). Mantenga el área de la herida esterilizado mediante la aplicación de solución quirúrgica clorhexidina. </li><li> Aplicar tratamientos post-quirúrgicos. Controlar el dolor del ratón con inyecciones subcutáneas de buprenorfina. Mantenga el ratón en la plataforma de calentamiento hasta que se haya recuperado sufciente conciencia de mantener decúbito esternal. Casa en una jaula limpia y sin compañía de otros animales hasta que se recuperó totalmente. </li></ol>

<ol>
	<li>Dzau, V. J., Braun-Dullaeus, R. C., Sedding, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vascular+proliferation+and+atherosclerosis:+new+perspectives+and+therapeutic+strategies.">Vascular proliferation and atherosclerosis: new perspectives and therapeutic strategies.</a> Nat Med. 8 (11), 1249-1256 (2002).</li><li>Hui, D. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intimal+hyperplasia+in+murine+models.">Intimal hyperplasia in murine models.</a> Curr Drug Targets. 9 (3), 251-260 (2008).</li><li>Ferns, G. A., Avades, T. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mechanisms+of+coronary+restenosis:+insights+from+experimental+models.">The mechanisms of coronary restenosis: insights from experimental models.</a> Int J Exp Pathol. 81 (2), 63-88 (2000).</li><li>Sata, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+mouse+model+of+vascular+injury+that+induces+rapid+onset+of+medial+cell+apoptosis+followed+by+reproducible+neointimal+hyperplasia.">A mouse model of vascular injury that induces rapid onset of medial cell apoptosis followed by reproducible neointimal hyperplasia.</a> J Mol Cell Cardiol. 32 (11), 2097-2104 (2000).</li><li>Xu, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+models+of+arteriosclerosis:+from+arterial+injuries+to+vascular+grafts.">Mouse models of arteriosclerosis: from arterial injuries to vascular grafts.</a> Am J Pathol. 165 (1), 1-10 (2004).</li><li>Lv, L., Meng, Q., Ye, M., Wang, P., Xue, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=STAT4+deficiency+protects+against+neointima+formation+following+arterial+injury+in+mice.">STAT4 deficiency protects against neointima formation following arterial injury in mice.</a> J Mol Cell Cardiol. 74C, 284-294 (2014).</li><li>Zhu, B., Kuhel, D. G., Witte, D. P., Hui, D. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Apolipoprotein+E+inhibits+neointimal+hyperplasia+after+arterial+injury+in+mice.">Apolipoprotein E inhibits neointimal hyperplasia after arterial injury in mice.</a> Am J Pathol. 157 (6), 1839-1848 (2000).</li><li>Fu, Y., Duru, E. A., Davies, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+metabolic+syndrome+on+the+response+to+arterial+injury.">Effect of metabolic syndrome on the response to arterial injury.</a> J Surg Res. , (2014).</li><li>Kuhel, D. G., Zhu, B., Witte, D. P., Hui, D. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distinction+in+genetic+determinants+for+injury-induced+neointimal+hyperplasia+and+diet-induced+atherosclerosis+in+inbred+mice.">Distinction in genetic determinants for injury-induced neointimal hyperplasia and diet-induced atherosclerosis in inbred mice.</a> Arterioscler Thromb Vasc Biol. 22 (6), 955-960 (2002).</li><li>Cooley, B. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+strain+differential+neointimal+response+in+vein+grafts+and+wire-injured+arteries.">Mouse strain differential neointimal response in vein grafts and wire-injured arteries.</a> Circ J. 71 (10), 1649-1652 (2007).</li><li>Ishigami, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deficiency+of+CuZn+superoxide+dismutase+promotes+inflammation+and+alters+medial+structure+following+vascular+injury.">Deficiency of CuZn superoxide dismutase promotes inflammation and alters medial structure following vascular injury.</a> J Atheroscler Thromb. 18 (11), 1009-1017 (2011).</li></ol>

The authors declare no competing financial interests.

El procedimiento lesión alambre es aplicable a todas las cepas de ratones, siempre y cuando sus estructuras anatómicas son similares. 4 En este trabajo, hemos utilizado macho C57BL / 6 ratones con una edad de 12 a 16 semanas. Como hemos aprendido de nuestros estudios preliminares, las arterias femorales de ratones más jóvenes de 10 semanas son a menudo tan pequeña que la inserción del alambre es todo un reto. Por otro lado, la inserción del alambre en ratones de más de 16 semanas es técnicamente más...

In the era of expanded application of endovascular treatments for various cardiovascular diseases, restenosis after angioplasty is one of the major problems for patients undergoing such treatments. Damage to the vascular endothelium at the time of angioplasty, in concert with the atherosclerotic background, induces excessive smooth muscle cell proliferation in the medial layer, resulting in neointimal hyperplasia.1,2 A viable animal model that recapitulates post-angioplasty neointimal hyperplasia is, thus, important not only for the investigation of disease mechanisms but also for the development of effective therapeutics to treat this pathology.
Mice represent an excellent model animal to recapitulate neointimal hyperplasia for the following reasons: the genetic backgrounds of experimental mice are well established; a wide variety of genetically-modified strains are available;2 obtaining littermates of the same background is easy; and the cost of the animals is relatively low. Arterial ligation model and wire injury model are the two most common mouse models of mechanically-induced neointimal hyperplasia. The arterial ligation model is easy to create, but physiologically dissimilar to the actual angioplasty procedure. The wire injury model closely mimics actual angioplasty procedures but is technically difficult due to the small size of mouse arteries.2,3 Sata et al. first described a wire injury method for mouse femoral arteries based on the anatomical structure of the vasculature and the use of proper-sized flexible wire. Utilizing this technique, they succeeded in reproducibly inducing neointimal hyperplasia in various strains of mice.4
Although femoral wire injury is a well-established model, some of the technical aspects of the technique are highly challenging compared to other models such as ligation.5 The purpose of this paper is to describe our mouse wire injury model procedures in detail, which is a modified version of Sata&#8217;s original method. We have made two main modifications: 1) Looping only the arteries, and 2) No lidocaine use.

<table><tbody><tr><td>Fixed Core Wire Guide</td><td>Cook</td><td>G02426</td><td>Diameter 0.015 inch, Straight</td></tr><tr><td>Dilation Forceps</td><td>Roboz</td><td>RS-4927</td><td>Curved, blunt tips</td></tr><tr><td>Dumont Tweesers #5</td><td>World Precision Instruments</td><td>14095</td><td>Straight, sharp tips</td></tr><tr><td>Dumont Vessel Cannulation Forceps</td><td>World Precision Instruments</td><td>503373</td><td></td></tr><tr><td>McPherson-Vannas Scissors</td><td>World Precision Instruments</td><td>501234</td><td></td></tr><tr><td>Mosquito Forceps</td><td>World Precision Instruments</td><td>501291</td><td></td></tr><tr><td>Ethilon Nylon Suture 9-0</td><td>Ethicon</td><td>7717G</td><td>9-0, Black Nylon Monofilament</td></tr><tr><td>Micro AROSuture, Sterile 11-0, 70 micrometers, MET Point</td><td>AROSurgical</td><td>VT4A00N07</td><td>11-0, Black Nylon Monofilament</td></tr><tr><td>3M Precise Multi-Shot DS Disposable Skin Stapler</td><td>3M</td><td>DS-25</td><td></td></tr></tbody></table>

a murine model of arterial restenosis: technical aspects of femoral wire injury

La enfermedad cardiovascular causada por la aterosclerosis es la causa principal de muerte en el mundo desarrollado. El estrechamiento de la luz del vaso, debido al desarrollo de la placa aterosclerótica o la ruptura de placas establecidos, interrumpe el flujo normal de la sangre que conduce a diversas morbilidades, tales como infarto de miocardio y accidente cerebrovascular. En los procedimientos endovasculares clínicas como la angioplastia se realizan comúnmente para reabrir el lumen. Sin embargo, estos tratamientos dañan inevitablemente la pared del vaso, así como el endotelio vascular, la activación de una respuesta de cicatrización excesiva y el desarrollo de una placa neointimal que se extiende en el lumen del vaso que causan la reestenosis (re-estrechamiento). La restenosis sigue siendo una causa importante de fracaso de los tratamientos endovasculares para la aterosclerosis. Por lo tanto, los modelos animales preclínicos de reestenosis son de vital importancia para la investigación de los mecanismos fisiopatológicos, así como de la traducción se acerca a las intervenciones vasculares. Entre varios EXPERIME murinomodelos NTAL, lesiones alambre arteria femoral es ampliamente aceptado como el más adecuado para estudios de reestenosis post-angioplastia porque se parece mucho al procedimiento de angioplastia que daña tanto el endotelio y la pared del vaso. Sin embargo, muchos investigadores tienen dificultades para la utilización de este modelo debido a su alto grado de dificultad técnica. Esto es principalmente porque un alambre de metal tiene que ser insertado en la arteria femoral, que es aproximadamente tres veces más delgado que el alambre, para generar suficiente para inducir la lesión neoíntima prominente. A continuación, describimos los detalles quirúrgicos esenciales para superar de manera efectiva las principales dificultades técnicas de este modelo. Siguiendo los procedimientos presentados, la realización de la lesión de alambre de la arteria femoral del ratón se vuelve más fácil. Una vez familiarizado, todo el procedimiento puede ser completado dentro de 20 min.

Cuatro semanas después de la cirugía, la cosecha de la arteria femoral alambre heridos y hacen muestra de bloque una parafina para analizar la formación de la neoíntima. Inducir la anestesia general como se describió anteriormente. Abra el pecho inmediatamente e inserte una mariposa aguja de calibre 20 al ventrículo izquierdo. Conecte la línea de una botella de infusión. Realizar fijación por perfusión a través de infusión por goteo de PBS seguido de paraformaldehído al 4% (por lo general 10 a 20 m...

Watch this Scientific Journal Video about A Murine Model of Arterial Restenosis: Technical Aspects of Femoral Wire Injury at JoVE.com

A Murine Model of Arterial Restenosis: Technical Aspects of Femoral Wire Injury

El modelo de lesión de alambre arteria femoral de ratón de la reestenosis es técnicamente difícil. En este protocolo se muestran los detalles técnicos clave esencial para llevar a cabo con éxito la lesión de alambre para inducir neointima consistente para estudios de reestenosis.

Un modelo murino de restenosis arterial: Aspectos Técnicos del femoral Lesiones alambre

Cardiovascular disease caused by atherosclerosis is the leading cause of death in the developed world. Narrowing of the vessel lumen, due to ...

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Research

JoVE Journal

Medicine

20.1K vistas.  University of Wisconsin School of Medicine and Public Health.  El modelo de lesión de alambre arteria femoral de ratón de la reestenosis es técnicamente difícil. En este protocolo se muestran los detalles técnicos clave esencial para llevar a cabo con éxito la lesión de alambre para inducir neointima consistente para estudios de reestenosis. 

Video: A Murine Model of Arterial Restenosis: Technical Aspects of Femoral Wire Injury

Murine Model of Hindlimb Ischemia 

In the United States, peripheral arterial disease (PAD) affects about 10 million individuals, and is also prevalent worldwide. Medical therapies for symptomatic relief are limited. Surgical or endovascular interventions are useful for some individuals, but long-term results are often disappointing. As a result, there is a need for developing new therapies to treat PAD. The murine hindlimb ischemia preparation is a model of PAD, and is useful for testing new therapies. When compared to other models of tissue ischemia such as coronary or cerebral artery ligation, femoral artery ligation provides for a simpler model of ischemic tissue. Other advantages of this model are the ease of access to the femoral artery and low mortality rate. 
In this video, we demonstrate the methodology for the murine model of unilateral hindimb ischemia. The specific materials and procedures for creating and evaluating the model will be described, including the assessment of limb perfusion by laser Doppler imaging. This protocol can also be utilized for the transplantation and non-invasive tracking of cells, which is demonstrated by Huang et al.1.

Murine Model of Hindlimb Ischemia

The surgical procedure for induction of unilateral hindlimb ischemia is demonstrated, with confirmation of ischemia by laser Doppler perfusion imaging.

Modelo murino de isquemia Miembro Posterior

In the United States, peripheral arterial disease (PAD) affects about 10 million individuals, and is also prevalent worldwide.  Medical therapies for ...

Investigación

Biología

Murine Spinotrapezius Model to Assess the Impact of Arteriolar Ligation on Microvascular Function and Remodeling

The murine spinotrapezius is a thin, superficial skeletal support muscle that extends from T3 to L4, and is easily accessible via dorsal skin incision. Its unique anatomy makes the spinotrapezius useful for investigation of ischemic injury and subsequent microvascular remodeling. Here, we demonstrate an arteriolar ligation model in the murine spinotrapezius muscle that was developed by our research team and previously published1-3. For certain vulnerable mouse strains, such as the Balb/c mouse, this ligation surgery reliably creates skeletal muscle ischemia and serves as a platform for investigating therapies that stimulate revascularization. Methods of assessment are also demonstrated, including the use of intravital and confocal microscopy. The spinotrapezius is well suited to such imaging studies due to its accessibility (superficial dorsal anatomy) and relative thinness (60-200 &mu;m). The spinotrapezius muscle can be mounted en face, facilitating imaging of whole-muscle microvascular networks without histological sectioning. We describe the use of intravital microscopy to acquire metrics following a functional vasodilation procedure; specifically, the increase in arterilar diameter as a result of muscle contraction. We also demonstrate the procedures for harvesting and fixing the tissues, a necessary precursor to immunostaining studies and the use of confocal microscopy.

We demonstrate a novel arterial ligation model in murine spinotrapezius muscle, including a step-by-step procedure and description of required instrumentation. We describe the surgery and relevant outcome measurements relating to vascular network remodeling and functional vasodilation using intravital and confocal microscopy.

Modelo murino Spinotrapezius para evaluar el impacto de la ligadura arteriolar en la función microvascular y Remodelación

The murine spinotrapezius is a thin, superficial skeletal support muscle that extends from T3 to L4, and is easily accessible via dorsal skin incision. ...

Medicina

A Murine Model of Stent Implantation in the Carotid Artery for the Study of Restenosis

Despite the considerable progress made in the stent development in the last decades, cardiovascular diseases remain the main cause of death in western countries. Beside the benefits offered by the development of different drug-eluting stents, the coronary revascularization bears also the life-threatening risks of in-stent thrombosis and restenosis. Research on new therapeutic strategies is impaired by the lack of appropriate methods to study stent implantation and restenosis processes. Here, we describe a rapid and accessible procedure of stent implantation in mouse carotid artery, which offers the possibility to study in a convenient way the molecular mechanisms of vessel remodeling and the effects of different drug coatings.

A model of stent implantation in mouse carotid artery is described. Compared to other similar methods, this procedure is very rapid, simple and accessible, offering the possibility to study in a convenient way the vascular wall reaction to different drug-eluting stents and the molecular mechanisms of restenosis.

Un modelo murino de la implantación de un stent en la arteria carótida para el Estudio de la reestenosis

Despite  the considerable progress made in the stent development in the last decades,  cardiovascular diseases remain the main cause of death in western ...

Generation and 3-Dimensional Quantitation of Arterial Lesions in Mice Using Optical Projection Tomography

The generation and analysis of vascular lesions in appropriate animal models is a cornerstone of research into cardiovascular disease, generating important information on the pathogenesis of lesion formation and the action of novel therapies. Use of atherosclerosis-prone mice, surgical methods of lesion induction, and dietary modification has dramatically improved understanding of the mechanisms that contribute to disease development and the potential of new treatments.
Classically, analysis of lesions is performed ex vivo using 2-dimensional histological techniques. This article describes application of optical projection tomography (OPT) to 3-dimensional quantitation of arterial lesions. As this technique is non-destructive, it can be used as an adjunct to standard histological and immunohistochemical analyses.
Neointimal lesions were induced by wire-insertion or ligation of the mouse femoral artery whilst atherosclerotic lesions were generated by administration of an atherogenic diet to apoE-deficient mice.
Lesions were examined using OPT imaging of autofluorescent emission followed by complementary histological and immunohistochemical analysis. OPT clearly distinguished lesions from the underlying vascular wall. Lesion size was calculated in 2-dimensional sections using planimetry, enabling calculation of lesion volume and maximal cross-sectional area. Data generated using OPT were consistent with measurements obtained using histology, confirming the accuracy of the technique and its potential as a complement (rather than alternative) to traditional methods of analysis.
This work demonstrates the potential of OPT for imaging atherosclerotic and neointimal lesions. It provides a rapid, much needed ex vivo technique for the routine 3-dimensional quantification of vascular remodelling.

Ex vivo analysis of arterial lesions from animal models of cardiovascular disease classically relies on histological and immunohistochemical techniques. These provide 2-dimensional measurements in 3-dimensional lesions. This manuscript describes the generation of arterial lesions for quantitative analysis in 3-dimensions using optical projection tomography.

Generación y cuantificación de 3 dimensiones de las lesiones arteriales en ratones mediante tomografía óptica de proyección

The generation and analysis of vascular lesions in appropriate animal models is a cornerstone of research into cardiovascular disease, generating ...

Murine Model of Femoral Artery Wire Injury with Implantation of a Perivascular Drug Delivery Patch

Percutaneous interventions including balloon angioplasty and stenting have been used to restore blood flow in vessels with occlusive vascular disease. While these therapies lead to the rapid restoration of blood flow, these technologies remain limited by restenosis in the case of bare metal stents and angioplasty, or reduced healing and possibly enhanced risk of thrombosis in the case of drug eluting stents. A key pathophysiological mechanism in the formation of restenosis is intimal hyperplasia caused by the activation of vascular smooth muscle cells and inflammation due to arterial stretch and injury. Surgeries that induce arterial injury in genetically modified mice are useful for the mechanistic study of the vascular response to injury but are often technically challenging to perform in mouse models due to the their small size and lack of appropriate sized devices. We describe two approaches for a surgical technique that induces endothelial denudation and arterial stretch in the femoral artery of mice to produce robust neointimal hyperplasia. The first approach creates an arteriotomy in the muscular branch of the femoral artery to obtain vascular access. Following wire injury this arterial branch is ligated to close the arteriotomy. A second approach creates an arteriotomy in the main femoral artery that is later closed through localized cautery. This method allows for vascular access through a larger vessel and, consequently, provides a less technically demanding procedure that can be used in smaller mice. Following either method of arterial injury, a degradable drug delivery patch can be placed over or around the injured artery to deliver therapeutic agents.

We describe a surgical technique that produces wire injury in the femoral artery of mice to induce neointimal hyperplasia to serve as a model testing system for the perivascular delivery of therapeutic compounds for the inhibition of restenosis.

Modelo murino de la arteria femoral Lesiones Alambre con implantación de un perivascular Drug Delivery Patch

Percutaneous interventions including balloon angioplasty and stenting have been used to restore blood flow in vessels with occlusive vascular disease. ...

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.

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. ...

Multiphoton Intravital Imaging for Monitoring Leukocyte Recruitment during Arteriogenesis in a Murine Hindlimb Model

Arteriogenesis strongly depends on leukocyte and platelet recruitment to the perivascular space of growing collateral vessels. The standard approach for analyzing collateral arteries and leukocytes in arteriogenesis is ex vivo (immuno-) histological methodology. However, this technique does not allow the measurement of dynamic processes such as blood flow, shear stress, cell-cell interactions, and particle velocity. This paper presents a protocol to monitor in vivo processes in growing collateral arteries during arteriogenesis utilizing intravital imaging. The method described here is a reliable tool for dynamics measurement and offers a high-contrast analysis with minimal photo-cytotoxicity, provided by multiphoton excitation microscopy. Prior to analyzing growing collateral arteries, arteriogenesis was induced in the adductor muscle of mice by unilateral ligation of the femoral artery.
After the ligation, the preexisting collateral arteries started to grow due to increased shear stress. Twenty-four hours after surgery, the skin and subcutaneous fat above the collateral arteries were removed, constructing a pocket for further analyses. To visualize blood flow and immune cells during in vivo imaging, CD41-fluorescein isothiocyanate (FITC) (platelets) and CD45-phycoerythrin (PE) (leukocytes) antibodies were injected intravenously (i.v.) via a catheter placed in the tail vein of a mouse. This article introduces intravital multiphoton imaging as an alternative or in vivo complementation to the commonly used static ex vivo (immuno-) histological analyses to study processes relevant for arteriogenesis. In summary, this paper describes a novel and dynamic in vivo method to investigate immune cell trafficking, blood flow, and shear stress in a hindlimb model of arteriogenesis, which enhances evaluation possibilities notably.

The recruitment of leukocytes and platelets constitutes an essential component necessary for the effective growth of collateral arteries during arteriogenesis. Multiphoton microscopy is an efficient tool for tracking cell dynamics with high spatio-temporal resolution in vivo and less photo-toxicity to study leukocyte recruitment and extravasation during arteriogenesis.

Imágenes intravitales multifotónicas para la monitorización del reclutamiento de leucocitos durante la arteriogénesis en un modelo de extremidades posteriores murinas

Arteriogenesis strongly depends on leukocyte and platelet recruitment to the perivascular space of growing collateral vessels. The standard approach for ...

High-Resolution Three-Dimensional Imaging of the Footpad Vasculature in a Murine Hindlimb Gangrene Model

Peripheral arterial disease (PAD) is a significant cause of morbidity resulting from chronic exposure to atherosclerotic risk factors. Patients suffering from its most severe form, chronic limb-threatening ischemia (CLTI), face substantial impairments to daily living, including chronic pain, limited walking distance without pain, and nonhealing wounds. Preclinical models have been developed in various animals to study PAD, but mouse hindlimb ischemia remains the most widely used. There can be significant variation in response to ischemic insult in these models depending on the mouse strain used and the site, number, and means of arterial disruption. This protocol describes a unique method combining femoral artery and vein electrocoagulation with the administration of a nitric oxide synthase (NOS) inhibitor to reliably induce footpad gangrene in Friend Virus B (FVB) mice that resembles the tissue loss of CLTI. While traditional means of assessing reperfusion such as laser Doppler perfusion imaging (LDPI) are still recommended, intracardiac perfusion of the lipophilic dye 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) is used to label the vasculature. Subsequent whole-mount confocal laser scanning microscopy allows for high-resolution, three-dimensional (3D) reconstruction of footpad vascular networks that complements traditional means of assessing reperfusion in hindlimb ischemia models.

The present protocol describes a unique, clinically relevant model of peripheral arterial disease that combines femoral artery and vein electrocoagulation with the administration of a nitric oxide synthase inhibitor to induce hindlimb gangrene in FVB mice. Intracardiac DiI perfusion is then used for high-resolution, three-dimensional imaging of the footpad vasculature.

Imágenes tridimensionales de alta resolución de la vasculatura de la almohadilla del pie en un modelo de gangrena de extremidades posteriores murinas

Peripheral arterial disease (PAD) is a significant cause of morbidity resulting from chronic exposure to atherosclerotic risk factors. Patients suffering ...

Murine Aortic Crush Injury: An Efficient In Vivo Model of Smooth Muscle Cell Proliferation and Endothelial Function

Arterial reconstruction, whether angioplasty or bypass surgery, involves iatrogenic trauma causing endothelial disruption and vascular smooth muscle cell (VSMC) proliferation. Common murine models study small vessels such as the carotid and femoral arteries. Herein we describe an in vivo system in which both VSMC proliferation and endothelial barrier function can be simultaneously assessed in a large vessel. We studied the infrarenal aortic response to injury in C57BL/6 mice. The aorta was injured from the left renal vein to the aortic bifurcation by 30 transmural crushes of 5-seconds duration with a cotton-tipped applicator. Morphological changes were assessed with conventional histology. Aorta wall thickness was measured from the luminal surface to the adventitia. EdU integration and counter staining with DAPI and alpha-actin was used to demonstrate VSMC proliferation. Activation of ERK1/2, a known moderator of intimal hyperplasia formation, was determined by Western Blot analysis. The effect of inflammation was determined by immunohistochemistry for B-cells, T-cells, and macrophages. En face sections of endothelium were visualized with scanning electron microscopy (SEM). Endothelial barrier function was determined with Evans Blue staining. Transmural injury resulted in aortic wall thickening. This injury induced VSMC proliferation, most prominently at 3 days after injury, and early activation of ERK1/2 and decreased p27kip1 expression. Injury did not result in increased B-cells, T-cells, or macrophages infiltration in the vessel wall. Injury caused partial endothelial cell denudation and loss of cell-cell contact. Injury resulted in a significant loss of endothelial barrier function, which returned to baseline after seven days. The murine transmural blunt aortic injury model provides an efficient system to simultaneously study both VSMC proliferation and endothelial barrier function in a large vessel.

Murine Aortic Crush Injury: An Efficient In Vivo Model of Smooth Muscle Cell Proliferation and Endothelial Function

Restenosis following cardiovascular procedures (bypass surgery, angioplasty, or stenting) is a significant problem reducing the durability of these procedures. An ideal therapy would inhibit smooth muscle cell (VSMC) proliferation while promoting regeneration of the endothelium. We describe a model for simultaneous assessment of VSMC proliferation and endothelial function in vivo.

Lesión por aplastamiento aórtico murino: una eficacia<em&gt; In Vivo</em&gt; Modelo de proliferación de células musculares lisas y función endotelial

Arterial reconstruction, whether angioplasty or bypass surgery, involves iatrogenic trauma causing endothelial disruption and vascular smooth muscle cell ...

Establishing a Diaphyseal Femur Fracture Model in Mice

Bones have a significant regenerative capacity. However, fracture healing is a complex process, and depending on the severity of the lesions and the age and overall health status of the patient, failures can occur, leading to delayed union or nonunion. Due to the increasing number of fractures resulting from high-energy trauma and aging, the development of innovative therapeutic strategies to improve bone repair based on the combination of skeletal/mesenchymal stem/stromal cells and biomimetic biomaterials is urgently needed. To this end, the use of reliable animal models is fundamental to better understanding the key cellular and molecular mechanisms that determine the healing outcomes. Of all the models, the mouse is the preferred research model because it offers a wide variety of transgenic strains and reagents for experimental analysis. However, the establishment of fractures in mice may be technically challenging due to their small size. Therefore, this article aims to demonstrate the procedures for the surgical establishment of a diaphyseal femur fracture in mice, which is stabilized with an intramedullary wire and resembles the most common bone repair process, through cartilaginous callus formation.

This protocol describes a surgical procedure for the establishment of a diaphyseal fracture in the femur of mice, which is stabilized with an intramedullary wire, for fracture healing studies.

Establecimiento de un modelo de fractura de fémur diafisario en ratones

Bones have a significant regenerative capacity. However, fracture healing is a complex process, and depending on the severity of the lesions and the age ...