Este trabajo fue apoyado por el NIH subvención NS057195, premio UCSF REAC, y Kent State University fondo inicial de WH Chou.

<html> 1. Método MCAO Este protocolo fue aprobado por el Comité Institucional y los Comités de Uso de la UCSF y la Universidad Estatal de Kent, y se rige por los Institutos Nacionales de Salud directrices para el uso de animales de experimentación. <ol></ol><ol><li> Cortar una sutura monofilamento 5-0 (Harvard Apparatus, Holliston, MA) en 20 segmentos mm. Alrededor de la punta de cada segmento por calentamiento cerca de un cauterizador (Braintree Scientific, Inc., Boston, MA). Mida el diámetro de la punta con un micrómetro (Applied Image Inc., Rochester, NY). Nosotros utilizamos una sutura con un diámetro de la punta final de 0,21-0,22 mm para un ratón con el peso corporal de 25 a 30 g. </li><li> Esterilizar todos los instrumentos quirúrgicos en autoclave (mínimo 121 ° C, 15 PSI, durante 15 minutos). Desinfectar la mesa de cirugía y el equipo asociado con etanol al 70%. </li><li> Anestesiar a un 8-12 semanas de edad del ratón (25-30 g) con 5% de isoflurano (Aerrane, Baxter, Deerfield, IL) en el 30% O 2 / 70% N 2 O con el sistema V-10 Anestesia (VetEquip, Inc ., Pleasanton, CA). Después de la inducción de la anestesia, reducir el nivel de isoflurano y mantenerlo en el 1,5%. </li><li> Coloque el ratón en la posición en decúbito supino sobre una almohadilla térmica. Insertar una sonda rectal, y vigilar y mantener la temperatura corporal entre 36,5 a 37,5 ° C con el TR-200 sistema de temperatura homeotermos (Fine Ciencia Tools Inc., Foster City, CA). </li><li> Afeitarse la piel en la región del cuello ventral con una maquinilla eléctrica (Braintree Científica) para exponer la piel. La desinfección de la zona quirúrgica con tres aplicaciones de etanol al 70%. </li><li> Bajo un microscopio estéreo de disección (Nikon, Japón), haga una incisión de 1 cm de largo la línea media del cuello. Utilice separadores (Braintree Scientific) para exponer el campo quirúrgico e identificar la arteria carótida común (CCA), arteria carótida externa (ACE), y la arteria carótida interna (ICA). Diseccionar cuidadosamente las arterias libres de alrededor de los nervios y la fascia. </li><li> Diseccionar la ECA más distal y la coagulación de la ECA y su arteria tiroidea superior (STA) rama con un coagulador bipolar (Howard Instrument Inc., Tuscaloosa, AL). Cortar la CEPA y la STA en el segmento de coagulación. </li><li> Vagamente eliminatoria a doble 8-0 suturas de seda alrededor del muñón ECA. Aplique una pinza vascular (Herramientas de Bellas Ciencia) en la bifurcación de la CCA en el Tribunal de Cuentas y de la ACI. </li><li> Haga una pequeña incisión en el extremo de la CEPA muñón con unas tijeras de primavera Vannas estilo (Herramientas de Bellas Ciencia). Medir y registrar la duración de una sutura monofilamento 5-0 redondeadas en la punta. Inserte la sutura en la incisión y avanzar a la abrazadera. Apriete los dos puntos de seda alrededor de la luz lo suficiente como para asegurar al mismo tiempo preservar la movilidad de la sutura monofilamento en vivienda. </li><li> Retire la abrazadera de la bifurcación. Suavemente avanzar en la sutura de monofilamento de la luz de la ECA en el ICA para una distancia de 9.10 mm más allá de la bifurcación de la CCA para ocluir el origen de la MCA. La duración de la cirugía es de aproximadamente 30-45 min. </li><li> Sutura de la incisión en el cuello y coloque el ratón en una caja de 35 ° C de enfermería para recuperarse de la anestesia, y devolverlo a la jaula. Generalmente se tarda 5-10 minutos para los ratones a recuperarse de la anestesia. Para llevar a cabo MCAO transitorios, el investigador puede volver a anestesiar el ratón y retirar la sutura de nuevo en el tronco de la CEPA después de un período de tiempo, generalmente entre 0,5 a 2 h. </li><li> Veinticuatro horas después de la inducción de MCAO, anestesiar el ratón con isoflurano 5% y la eutanasia por dislocación cervical. Decapitar el ratón y recoger el cerebro. Cortar el cerebro coronal en cuatro rodajas de 2 mm con una matriz de cerebro (Braintree Scientific) en el hielo. Se incuban las rodajas de cerebro en el 2% de cloruro de 2,3,5-trifenil tetrazolio (TTC) (Sigma-Aldrich) en 1X PBS durante 20 minutos a temperatura ambiente para determinar el tamaño y la extensión del infarto. Fijar las rodajas de cerebro en el 10% neutral solución de formalina tamponada (Sigma-Aldrich) a 4 ° C hasta que la imagen. La extensión del infarto se puede cuantificar como se describe en el protocolo JoVe 955 ( <a href="http://www.jove.com/index/Details.stp?ID=955">http://www.jove.com/index/Details.stp?ID=955</a> ) 9. </li></ol> 2. Resultados representante <ol></ol> Los infartos generados por MCAO se ven en el cuerpo estriado y la corteza dorsolateral. El estriado es más sensible a la isquemia de la corteza cerebral. Treinta minutos de MCAO producirá un infarto sólo en el cuerpo estriado, mientras que más de una hora de MCAO dañar tanto el cuerpo estriado y la corteza. Después de 24 h MCAO permanente, el porcentaje total de infarto es de ~ 40 ± 5% del hemisferio y la tasa de mortalidad después de la cirugía es de alrededor del 10%. Se excluye a los ratones de más estudios, si se produce un sangrado excesivo durante la cirugía, el tiempo de funcionamiento supera los 90 minutos, los ratones no recuperarse de la anestesia en los 15 minutos, o la hemorragia se encuentra en las secciones de cerebro o en la base del círculo de Willis durante el examen post-mortem . jove_content &quot;&gt; <img src="/files/ftp_upload/2761/2761fig1.jpg" alt="Figura 1" /> Figura 1. Imágenes representativas de las secciones de cerebro TTC-manchada (nivel coronal 1-4) después de 24 h de MCAO permanente. En el tejido vivo TTC es enzimáticamente reducido por deshidrogenasas de 1,3,5-triphenylformazan (TPF), que es de color rojo, mientras que en las áreas necróticas sigue siendo blanco debido a la ausencia de actividad enzimática tales. Por lo tanto, el área de infarto se puede identificar por su color blanco debido a la falta de conversión de TTC para TPF. Nota: TTC es un tanto calor y la luz inestable para proteger a las secciones teñidas de luz y calor tanto como sea posible.

<ol>
	<li>Howard, G., Howard, V. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Distribution of stroke: hetrogeneity of stroke by age, and sex. , 3-12 (2004).</li><li>Thom, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heart+disease+and+stroke+statistics--2006+update:+a+report+from+the+American+Heart+Association+Statistics+Committee+and+Stroke+Statistics+Subcommittee.">Heart disease and stroke statistics--2006 update: a report from the American Heart Association Statistics Committee and Stroke Statistics Subcommittee.</a> Circulation. 113, e85-e151 (2006).</li><li>Mohr, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Middle cerebral artery disease. , 123-166 (2004).</li><li>Longa, E. Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reversible+middle+cerebral+artery+occlusion+without+craniectomy+in+rats.">Reversible middle cerebral artery occlusion without craniectomy in rats.</a> Stroke. 20, 84-91 (1989).</li><li>Chou, W. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neutrophil+protein+kinase+Cdelta+as+a+mediator+of+stroke-reperfusion+injury.">Neutrophil protein kinase Cdelta as a mediator of stroke-reperfusion injury.</a> J. Clin. Invest. 114, 49-56 (2004).</li><li>Hudgins, W. R., Garcia, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+electrocautery,+atmospheric+exposure,+and+surgical+retraction+on+the+permeability+of+the+blood-brain-barrier.">The effect of electrocautery, atmospheric exposure, and surgical retraction on the permeability of the blood-brain-barrier.</a> Stroke. 1, 375-380 (1970).</li><li>Carmichael, S. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rodent+models+of+focal+stroke:+size,+mechanism,+and+purpose.">Rodent models of focal stroke: size, mechanism, and purpose.</a> NeuroRx. 2, 396-409 (2005).</li><li>Durukan, A., Tatlisumak, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acute+ischemic+stroke:+overview+of+major+experimental+rodent+models,+pathophysiology,+and+therapy+of+focal+cerebral+ischemia.">Acute ischemic stroke: overview of major experimental rodent models, pathophysiology, and therapy of focal cerebral ischemia.</a> Pharmacol. Biochem. Behav. 87, 179-197 (2007).</li><li>Taniguchi, H., Andreasson, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+hypoxic-ischemic+encephalopathy+model+of+perinatal+ischemia.">The hypoxic-ischemic encephalopathy model of perinatal ischemia.</a> J Vis Exp. , (2008).</li></ol>

No tenemos ningún interés en conflicto potencial de revelar.

MCAO en ratones se utiliza comúnmente para modelo de isquemia cerebral focal en los seres humanos. El uso de ratones para los estudios de tiempos cada vez más frecuente debido a la disponibilidad de las cepas de transgénicos y knock-out. Hay algunos detalles fundamental tener en cuenta en el protocolo: <ol><li> Es esencial para mantener la temperatura del cuerpo del ratón durante la cirugía y antes de que se recupere completamente de la anestesia. La temperatura corporal tiene efectos sobre la extensión del infarto, disminuye la hipotermia y la hipertermia aumenta el tamaño del infarto. </li><li> Mientras que la exposición y el aislamiento de la CCA y la CEPA, evitar daños en el nervio vago cerca y la tráquea, lo que podría aumentar el tamaño del infarto y la viabilidad de disminuir. </li><li> Nunca introduzca la sutura monofilamento de más de 10 mm de paso de la bifurcación. Una sutura insertado demasiado lejos puede perforar la arteria cerebral anterior y el resultado de una hemorragia cerebral. A la resistencia se puede sentir cuando la sutura se avanza unos 9-10 mm más allá del punto de bifurcación. Si esto ocurre, el investigador debe detener el avance de la sutura y confirmar la distancia. </li></ol>

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mouse model of middle cerebral artery occlusion

El accidente cerebrovascular es la más común enfermedad neurológica mortal en los Estados Unidos 1. La mayoría de los accidentes cerebrovasculares (88%) son el resultado de la obstrucción de los vasos sanguíneos en el cerebro (apoplejía isquémica) 2. Como la mayoría de los accidentes cerebrovasculares isquémicos (80%) se producen en el territorio de la arteria cerebral media (ACM) 3, muchos modelos animales tiempos que se han desarrollado se han centrado en esta arteria. El modelo de monofilamento intraluminal de arteria cerebral media oclusión (MCAO) consiste en la inserción de un filamento de cirugía en la arteria carótida externa y los hilos que a la arteria carótida interna (ACI) hasta que la punta ocluye el origen de la MCA, dando lugar a un cese del flujo sanguíneo e infarto cerebral posterior en el territorio de la ACM 4. La técnica puede ser utilizada para modelar la oclusión permanente o transitoria 5. Si la sutura se retira después de un intervalo determinado (30 min, 1 h, o h 2), se logra la reperfusión (transitoria MCAO), si el filamento se deja en su lugar (24 h) el procedimiento es adecuado como un modelo de permanente MCAO . Esta técnica no requiere la craniectomía, un procedimiento neuroquirúrgico para eliminar una parte del cráneo, que puede afectar la presión intracraneal y la temperatura 6. Se ha convertido en el método más frecuentemente utilizado para imitar permanentes y transitorios de isquemia cerebral focal en ratas y ratones 7,8. Para evaluar la extensión del infarto cerebral, que mancha las secciones de cerebro con cloruro de 2,3,5-trifenil tetrazolio (TTC) para identificar el tejido cerebral isquémico 9. En este vídeo, se demuestra el método MCAO y la determinación del tamaño del infarto por tinción con TTC.

Watch this Scientific Journal Video about Mouse Model of Middle Cerebral Artery Occlusion at JoVE.com

Mouse Model of Middle Cerebral Artery Occlusion

Se demuestra en el video de un método para producir una oclusión de arteria cerebral media en ratones adultos con un monofilamento intraluminal. También mostrará cómo evaluar la extensión del infarto cerebral por el cloruro de 2,3,5-trifenil tetrazolio (TTC) tinción.

Modelo de ratón de la oclusión arteria cerebral media

Stroke is the most common fatal neurological disease in the United States 1. The majority of strokes (88%) result from blockage of blood vessels in the ...

mouse-model-of-middle-cerebral-artery-occlusion

Research

JoVE Journal

Medicine

77.5K vistas.  Ernest Gallo Clinic and Research Center, University of California, San Francisco. Se demuestra en el video de un método para producir una oclusión de arteria cerebral media en ratones adultos con un monofilamento intraluminal. También mostrará cómo evaluar la extensión del infarto cerebral por el cloruro de 2,3,5-trifenil tetrazolio (TTC) tinción.

Video: Mouse Model of Middle Cerebral Artery Occlusion

Modeling Stroke in Mice - Middle Cerebral Artery Occlusion with the Filament Model

Stroke is among the most frequent causes of death and adult disability, especially in highly developed countries. However, treatment options to date are very limited. To meet the need for novel therapeutic approaches, experimental stroke research frequently employs rodent models of focal cerebral ischaemia. Most researchers use permanent or transient occlusion of the middle cerebral artery (MCA) in mice or rats.
Proximal occlusion of the middle cerebral artery (MCA) via the intraluminal suture technique (so called filament or suture model) is probably the most frequently used model in experimental stroke research. The intraluminal MCAO model offers the advantage of inducing reproducible transient or permanent ischaemia of the MCA territory in a relatively non-invasive manner. Intraluminal approaches interrupt the blood flow of the entire territory of this artery. Filament occlusion thus arrests flow proximal to the lenticulo-striate arteries, which supply the basal ganglia. Filament occlusion of the MCA results in reproducible lesions in the cortex and striatum and can be either permanent or transient. In contrast, models inducing distal (to the branching of the lenticulo-striate arteries) MCA occlusion typically spare the striatum and primarily involve the neocortex. In addition these models do require craniectomy. In the model demonstrated in this article, a silicon coated filament is introduced into the common carotid artery and advanced along the internal carotid artery into the Circle of Willis, where it blocks the origin of the middle cerebral artery. In patients, occlusions of the middle cerebral artery are among the most common causes of ischaemic stroke. Since varying ischemic intervals can be chosen freely in this model depending on the time point of reperfusion, ischaemic lesions with varying degrees of severity can be produced. Reperfusion by removal of the occluding filament at least partially models the restoration of blood flow after spontaneous or therapeutic (tPA) lysis of a thromboembolic clot in humans.
In this video we will present the basic technique as well as the major pitfalls and confounders which may limit the predictive value of this model.

Filamentous occlusion of the Middle cerebral artery is a common model for studying ischemic stroke in mice.

Modelado de accidente cerebrovascular en ratones - Oclusión arteria cerebral media con el modelo de filamento

Stroke is among the most frequent causes of death and adult disability, especially in highly developed countries. However, treatment options to date are ...

Investigación

Medicina

Intraluminal Middle Cerebral Artery Occlusion (MCAO) Model for Ischemic Stroke with Laser Doppler Flowmetry Guidance in Mice

Stroke is the third leading cause of death and the leading cause of disability in the world, with an estimated cost of near $70 billion 
in the United States in 20091,2. The intraluminal middle cerebral artery occlusion (MCAO) model was developed by Koizumi4 in 1986 to simulate this 
impactful human pathology in the rat. A modification of the MCAO method was later presented by Longa3. Both techniques have been widely used to identify 
molecular mechanisms of brain injury resulting from ischemic stroke and potential therapeutic modalities5. This relatively noninvasive method in rats has been 
extended to use in mice to take advantage of transgenic and knockout strains6,7. To model focal cerebral ischemia, an intraluminal suture is advanced via 
the internal carotid artery to occlude the base of the MCA. Retracting the suture after a specified period of time mimics spontaneous reperfusion, but the 
suture can also be permanently retained. This video will be demonstrating the two major approaches for performing intraluminal MCAO procedure in mice in a 
stepwise fashion, as well as providing insights for potential drawbacks and pitfalls. The ischemic brain tissue will subsequently be stained by 
2,3,5-triphenyltetrazolium chloride (TTC) to evaluate the extent of cerebral infarction8.

Intraluminal Middle Cerebral Artery Occlusion MCAO Model for Ischemic Stroke with Laser Doppler Flowmetry Guidance in Mice

The intraluminal middle cerebral artery occlusion (MCAO) model is the most frequent used model among experimental ischemic stroke models. Here we will demonstrate the entire model in detail with the guide of Laser Doppler flowmetry, and its representative results.

Intraluminal la arteria cerebral media de oclusión (MCAO) Modelo para el ictus isquémico con Orientación flujometría láser Doppler en ratones

Stroke is the third leading cause of death and the leading cause of disability in the world, with an estimated cost of near $70 billion 
in the United ...

The Application Of Permanent Middle Cerebral Artery Ligation in the Mouse

Focal cerebral ischemia is among the most common type of stroke seen in patients. Due to the clinical significance there has been a prolonged effort to develop suitable animal models to study the events that unfold during ischemic insult. These techniques include transient or permanent, focal or global ischemia models using many different animal models, with the most common being rodents.
The permanent MCA ligation method which is also referred as pMCAo in the literature is used extensively as a focal ischemia model in rodents 1-6. This method was originally described for rats by Tamura et al. in 1981 7. In this protocol a craniotomy was used to access the MCA and the proximal regions were occluded by electrocoagulation. The infarcts involve mostly cortical and sometimes striatal regions depending on the location of the occlusion. This technique is now well established and used in many laboratories 8-13. Early use of this technique led to the definition and description of &#x201C;infarct core&#x201D; and &#x201C;penumbra&#x201D; 14-16, and it is often used to evaluate potential neuroprotective compounds 10, 12, 13, 17. Although the initial studies were performed in rats, permanent MCA ligation has been used successfully in mice with slight modifications 18-20 .
This model yields reproducible infarcts and increased post-survival rates. Approximately 80% of the ischemic strokes in humans happen in the MCA area 21 and thus this is a very relevant model for stroke studies. Currently, there is a paucity of effective treatments available to stroke patients, and thus there is a need for good models to test potential pharmacological compounds and evaluate physiological outcomes. This method can also be used for studying intracellular hypoxia response mechanisms in vivo. 
Here, we present the MCA ligation surgery in a C57/BL6 mouse. We describe the pre-surgical preparation, MCA ligation surgery and 2,3,5 Triphenyltetrazolium chloride (TTC) staining for quantification of infarct volumes.

Middle cerebral artery (MCA) ligation is a technique to study focal cerebral ischemia in animal models. In this method, the middle cerebral artery is exposed by craniotomy and ligated by cauterization. This method gives highly reproducible infarct volumes and increased post-operative survival rates compared to other methods available.

La aplicación de la Permanente Ligadura arteria cerebral media en el ratón

Focal cerebral ischemia is among the most common type of stroke seen in patients. Due to the clinical significance there has been a prolonged effort to ...

Endothelin-1 Induced Middle Cerebral Artery Occlusion Model for Ischemic Stroke with Laser Doppler Flowmetry Guidance in Rat

Stroke is the number one cause of disability and third leading cause of death in the world, costing an estimated $70 billion in the United States in 20091, 2. Several models of cerebral ischemia have been developed to mimic the human condition of stroke. It has been suggested that up to 80% of all strokes result from ischemic damage in the middle cerebral artery (MCA) area3. In the early 1990s, endothelin-1 (ET-1) 4 was used to induce ischemia by applying it directly adjacent to the surface of the MCA after craniotomy. Later, this model was modified 5 by using a stereotaxic injection of ET-1 adjacent to the MCA to produce focal cerebral ischemia. The main advantages of this model include the ability to perform the procedure quickly, the ability to control artery constriction by altering the dose of ET-1 delivered, no need to manipulate the extracranial vessels supplying blood to the brain as well as gradual reperfusion rates that more closely mimics the reperfusion in humans5-7. On the other hand, the ET-1 model has disadvantages that include the need for a craniotomy, as well as higher variability in stroke volume8. This variability can be reduced with the use of laser Doppler flowmetry (LDF) to verify cerebral ischemia during ET-1 infusion. Factors that affect stroke variability include precision of infusion and the batch of the ET-1 used6. Another important consideration is that although reperfusion is a common occurrence in human stroke, the duration of occlusion for ET-1 induced MCAO may not closely mimic that of human stroke where many patients have partial reperfusion over a period of hours to days following occlusion9, 10. This protocol will describe in detail the ET-1 induced MCAO model for ischemic stroke in rats. It will also draw attention to special considerations and potential drawbacks throughout the procedure.

Several animal models of cerebral ischemia have been developed to simulate the human condition of stroke. This protocol describes the endothelin-1 (ET-1) induced middle cerebral artery occlusion (MCAO) model for ischemic stroke in rats. In addition, important considerations, advantages, and shortcomings of this model are discussed.

La endotelina-1 inducida por la arteria cerebral media oclusión Modelo para el ictus isquémico con Orientación flujometría láser Doppler en la rata

Stroke is the number one cause of disability and third leading cause of death in the world, costing an estimated $70 billion in the United States in ...

Utilizing a Cranial Window to Visualize the Middle Cerebral Artery During Endothelin-1 Induced Middle Cerebral Artery Occlusion

Creation of a cranial window is a method that allows direct visualization of structures on the cortical surface of the brain1-3. This technique can be performed in many locations overlying the rat cerebrum, but is most easily carried out by creating a craniectomy over the readily accessible frontal or parietal bones. Most frequently, we have used this technique in combination with the endothelin-1 middle cerebral artery occlusion model of ischemic stroke to quantify the changes in middle cerebral artery vessel diameter that occur with injection of endothelin-1 into the brain parenchyma adjacent to the proximal MCA4, 5. In order to visualize the proximal portion of the MCA during endothelin -1 induced MCAO, we use a technique to create a cranial window through the temporal bone on the lateral aspect of the rat skull (Figure 1). Cerebral arteries can be visualized either with the dura intact or with the dura incised and retracted. Most commonly, we leave the dura intact during visualization since endothelin-1 induced MCAO involves delivery of the vasoconstricting peptide into the brain parenchyma. This bypasses the need to incise the dura directly over the visualized vessels for drug delivery. This protocol will describe how to create a cranial window to visualize cerebral arteries in a step-wise fashion, as well as how to avoid many of the potential pitfalls pertaining to this method.

This article describes a method for visualizing rat cerebral arteries through a cranial window using temporal craniectomy in order to view proximal portions of the middle cerebral artery (Figure 1). This versatile method can be combined with various techniques of drug delivery to measure cerebral artery reactivity in vivo.

Utilizando una ventana craneal para visualizar la arteria cerebral media Durante la endotelina-1 inducida por oclusión de la arteria cerebral media

Creation of a cranial window is a method that allows direct visualization of structures on the cortical surface of the brain1-3. This technique can be ...

Optimized System for Cerebral Perfusion Monitoring in the Rat Stroke Model of Intraluminal Middle Cerebral Artery Occlusion

The translational potential of pre-clinical stroke research depends on the accuracy of experimental modeling. Cerebral perfusion monitoring in animal models of acute ischemic stroke allows to confirm successful arterial occlusion and exclude subarachnoid hemorrhage. Cerebral perfusion monitoring can also be used to study intracranial collateral circulation, which is emerging as a powerful determinant of stroke outcome and a possible therapeutic target. Despite a recognized role of Laser Doppler perfusion monitoring as part of the current guidelines for experimental cerebral ischemia, a number of technical difficulties exist that limit its widespread use. One of the major issues is obtaining a secure and prolonged attachment of a deep-penetration Laser Doppler probe to the animal skull. In this video, we show our optimized system for cerebral perfusion monitoring during transient middle cerebral artery occlusion by intraluminal filament in the rat. We developed in-house a simple method to obtain a custom made holder for twin-fibre (deep-penetration) Laser Doppler probes, which allow multi-site monitoring if needed. A continuous and prolonged monitoring of cerebral perfusion could easily be obtained over the intact skull.

Cerebral perfusion monitoring has been demonstrated to improve accuracy in ischemic stroke models. Technical difficulties often limit the use of this essential tool for cerebrovascular research. In this video, an optimized system is shown to obtain a single or multi-site hemodynamic monitoring during intraluminal middle cerebral artery occlusion in rats.

Sistema optimizado para la monitorización de la perfusión cerebral en el modelo de rata de Carrera intraluminal oclusión arteria cerebral media

The translational potential of pre-clinical stroke research depends on the accuracy of experimental modeling. Cerebral perfusion monitoring in animal ...

Embolic Middle Cerebral Artery Occlusion (MCAO) for Ischemic Stroke with Homologous Blood Clots in Rats

Clinically, thrombolytic therapy with use of recombinant tissue plasminogen activator (tPA) remains the most effective treatment for acute ischemic stroke. However, the use of tPA is limited by its narrow therapeutic window and by increased risk of hemorrhagic transformation. There is an urgent need to develop suitable stroke models to study new thrombolytic agents and strategies for treatment of ischemic stroke. At present, two major types of ischemic stroke models have been developed in rats and mice: intraluminal suture MCAO and embolic MCAO. Although MCAO models via the intraluminal suture technique have been widely used in mechanism-driven stroke research, these suture models do not mimic the clinical situation and are not suitable for thrombolytic studies. Among these models, the embolic MCAO model closely mimics human ischemic stroke and is suitable for preclinical investigation of thrombolytic therapy. This embolic model was first developed in rats by Overgaard et al.1 in 1992 and further characterized by Zhang et al. in 19972. Although embolic MCAO has gained increasing attention, there are technical problems faced by many laboratories. To meet increasing needs for thrombolytic research, we present a highly reproducible model of embolic MCAO in the rat, which can develop a predictable infarct volume within the MCA territory. In brief, a modified PE-50 tube is gently advanced from the external carotid artery (ECA) into the lumen of the internal carotid artery (ICA) until the tip of the catheter reaches the origin of the MCA. Through the catheter, a single homologous blood clot is placed at the origin of the MCA. To identify the success of MCA occlusion, regional cerebral blood flow was monitored, neurological deficits and infarct volumes were measured. The techniques presented in this paper should help investigators to overcome technical problems for establishing this model for stroke research.

Embolic Middle Cerebral Artery Occlusion MCAO for Ischemic Stroke with Homologous Blood Clots in Rats

In this paper, we demonstrate a standard method for producing an embolic middle cerebral artery occlusion with homologous blood clots (fibrin-rich) in adult rat. This model closely mimics human ischemic stroke and is suitable for preclinical study of thrombolytic therapy for ischemic stroke.

Arteria embólico cerebral media oclusión (MCAO) para el ictus isquémico con homólogas coágulos de sangre en las ratas

Clinically, thrombolytic therapy with use of recombinant tissue plasminogen activator (tPA) remains the most effective treatment for acute ischemic ...

Quantification of Neurovascular Protection Following Repetitive Hypoxic Preconditioning and Transient Middle Cerebral Artery Occlusion in Mice

Experimental animal models of stroke are invaluable tools for understanding stroke pathology and developing more effective treatment strategies. A 2 week protocol for repetitive hypoxic preconditioning (RHP) induces long-term protection against central nervous system (CNS) injury in a mouse model of focal ischemic stroke. RHP consists of 9 stochastic exposures to hypoxia that vary in both duration (2 or 4 hr) and intensity (8% and 11% O2). RHP reduces infarct volumes, blood-brain barrier (BBB) disruption, and the post-stroke inflammatory response for weeks following the last exposure to hypoxia, suggesting a long-term induction of an endogenous CNS-protective phenotype. The methodology for the dual quantification of infarct volume and BBB disruption is effective in assessing neurovascular protection in mice with RHP or other putative neuroprotectants. Adult male Swiss Webster mice were preconditioned by RHP or duration-equivalent exposures to 21% O2 (i.e. room air). A 60 min transient middle cerebral artery occlusion (tMCAo) was induced 2 weeks following the last hypoxic exposure. Both the occlusion and reperfusion were confirmed by transcranial laser Doppler flowmetry. Twenty-two hr after reperfusion, Evans Blue (EB) was intravenously administered through a tail vein injection. 2 hr later, animals were sacrificed by isoflurane overdose and brain sections were stained with 2,3,5- triphenyltetrazolium chloride (TTC). Infarcts volumes were then quantified. Next, EB was extracted from the tissue over 48 hr to determine BBB disruption after tMCAo. In summary, RHP is a simple protocol that can be replicated, with minimal cost, to induce long-term endogenous neurovascular protection from stroke injury in mice, with the translational potential for other CNS-based and systemic pro-inflammatory disease states.

This protocol describes repetitive hypoxic preconditioning, or brief exposures to systemic hypoxia that reduce infarct volumes and blood-brain barrier disruption following transient middle cerebral artery occlusion in mice. It also details dual quantification of infarct volume and blood-brain barrier disruption after stroke to assess the efficacy of neurovascular protection.

Cuantificación de Protección neurovascular Siguiendo repetitivo hipóxico Precondicionamiento y transitoria cerebral media oclusión de la arteria en ratones

Experimental animal models of stroke are invaluable tools for understanding stroke pathology and developing more effective treatment strategies. A 2 week ...

Surgical Approach for Middle Cerebral Artery Occlusion and Reperfusion Induced Stroke in Mice

Stroke is a leading cause of death worldwide and continues to be one of the major causes of long-term adult disabilities. About 87% of strokes are ischemic in origin and occur in the territory of the middle cerebral artery (MCA). Currently the only Food and Drug Administration (FDA) approved drug for the treatment of this devastating disease is tissue plasminogen activator (tPA). However, tPA has a small therapeutic window for administration (3 - 6 hr), and is only effective in 4% of the patients who actually receive it. Current research focuses on understanding the pathophysiology of stroke in order to find potential therapeutic targets. Thus, reliable models are crucial, and the MCA occlusion (MCAo) model (also termed the intraluminal filament or suture model) is deemed to be the most clinically relevant surgical model of ischemic stroke, and is fairly non-invasive and easily reproducible. Typically the MCAo model is used with rodents, especially with mice due to all the genetic variations available for this species. Here we describe (and present in the video) how to successfully perform the MCAo model (with reperfusion) in mice to generate reliable and reproducible data.

In order to understand the pathophysiology of stroke, it is important to use reliable models. This paper will describe one of the most frequently used stroke models in mice, termed the middle cerebral artery occlusion (MCAo) model (also termed the intraluminal filament or suture model) with reperfusion.

Técnica quirúrgica para la oclusión de la arteria cerebral media y la reperfusión del movimiento inducidos en ratones

Stroke is a leading cause of death worldwide and continues to be one of the major causes of long-term adult disabilities. About 87% of strokes are ...

Transient Middle Cerebral Artery Occlusion Model of Neonatal Stroke in P10 Rats

A number of animal models have been used to study hypoxic-ischemic injury, traumatic injury, global hypoxia, or permanent ischemia in both the immature and mature brain. Stroke occurs commonly in the perinatal period in humans, and transient ischemia-reperfusion is the most common form of stroke in neonates. The reperfusion phase is a critical component of injury progression, which occurs over a period of days to weeks, and of the endogenous response to injury. This postnatal day 10 (p10) rat model of transient middle cerebral artery occlusion (tMCAO) creates a unilateral, non-hemorrhagic focal ischemia-reperfusion injury that can be utilized to study the mechanisms of focal injury and repair in the full-term-equivalent brain. The injury pattern that is produced by tMCAO is consistent and highly reproducible and can be confirmed with MRI or histological analyses. The severity of injury can be manipulated through changes in occlusion time and other methods that will be discussed.

Neonatal stroke is a significant cause of early brain injury requiring a translational model with consistent focal injury patterns and high reproducibility in order to enable study. This study describes the detailed surgical procedure for creating a non-hemorrhagic, unilateral focal ischemia-reperfusion injury in full-term-equivalent rodents.

Transitoria de la arteria cerebral media oclusión Modelo de accidente cerebrovascular neonatal en ratas P10

A number of animal models have been used to study hypoxic-ischemic injury, traumatic injury, global hypoxia, or permanent ischemia in both the immature ...