Special thanks to the Gidday lab for their work in developing the RHP protocol, as well as the Neuro-Models Facility (UTSW) for their assistance in the tMCAo surgeries. This work was supported by grants from the American Heart Association (AMS), The Haggerty Center for Brain Injury and Repair (UTSW; AMS), and The Spastic Paralysis Research Foundation of the Illinois-Eastern Iowa District of Kiwanis International (JMG).

The authors have nothing to disclose.

Una singola esposizione ad ipossia sistemica (ad esempio, 2 ore del 11% O 2) in topi &quot;transitoriamente&quot; protegge il cervello da tMCAo, 29 cioè la risposta epigenetico alla sfida precondizionamento ipossico è di breve durata, e il fenotipo di base viene ripristinata entro giorni. Presentazioni ripetitive dello stimolo precondizionamento ipossico estendono notevolmente la durata del fenotipo neuroprotettivo. 6 Molti studi hanno dimostrato che la frequenza, ampiezza e d...

Come la principale causa di disabilità adulta e la quarta causa di morte, ictus è una delle patologie più debilitanti di fronte alla popolazione adulta degli Stati Uniti. 1 I modelli animali di ictus permettono di indagine sperimentale di nuovi metodi per ridurre il danno ischemico e migliorare il recupero post-ictus. Una strada nuova per questo tipo di ricerca traslazionale è precondizionamento. Precondizionamento è l&#39;uso intenzionale di uno stimolo non dannosi per ridurre i danni da una successiva e più grave, lesioni. 2 Hypoxic precondizionamento ha dimostrato di produrre cambiamenti pleiotropici nel cervello che forniscono protezione contro ictus sia in vivo e in vitro . 3 Tuttavia, una singola esposizione all&#39;ipossia offre solo neuroprotezione a breve termine, inducendo a meno di 72 ore di tolleranza nei confronti dell&#39;ischemia in topi adulti. 4 anche dopo quattro settimane di 14 hr esposizioni quotidiane all&#39;ipossia ipobarica, Lin et al. found che neuroprotezione è stato sostenuto solo per una settimana. 5 precondizionamento ipossico ripetitiva (RHP) è caratterizzato da variazioni stocastiche in frequenza, la durata e l&#39;intensità delle esposizioni ipossiche. A differenza di una singola sfida precondizionamento, RHP induce un fenotipo cerebroprotective che dura fino a otto settimane nei topi. 6 RHP ridotti volumi infarto, barriera emato-encefalica (BBB) ​​rottura, infiammazione vascolare, e dei leucociti diapedesi per settimane dopo l&#39;esposizione ipossica finale . RHP particolare ha ridotto l&#39;infiammazione nel cervello ischemico attraverso la riduzione delle cellule T, monociti, macrofagi e le popolazioni, pur mantenendo popolazioni di cellule B nell&#39;emisfero ischemico. 7, infatti, RHP indotto un fenotipo immunosoppressivo nei topi prima di eventuali lesioni del sistema nervoso centrale, tra cui l&#39;ictus. Cellule B RHP-trattati isolati da RHP trattati topi sani mostravano un fenotipo antinfiammatorio unico, con una sottoregolazione sia presentazione dell&#39;antigene e la produzione di anticorpi. Ilriduzione complessiva pro-infiammatorie meccanismi immunitari adattivi rende RHP una metodologia eccellente per indurre immunosoppressione endogena non solo per le malattie infiammatorie del sistema nervoso centrale-specifici, ma anche modelli di infortunio o malattia sistemica che includono una patologia pro-infiammatoria. RHP riduce sia il volume dell&#39;infarto e BBB rottura dopo un transitorio mezzo occlusione dell&#39;arteria cerebrale (tMCAo). I modelli animali di ictus, come comunemente usato tMCAo, migliorano notevolmente la comprensione della fisiopatologia di ictus, nonché la progettazione di neurotherapeutics più efficaci. Prima sviluppato da Koizumi et al., 1986, 8 la procedura tMCAo è un metodo ampiamente utilizzato per indurre ictus nei roditori e uno dei metodi preferiti per indagare infiammazione seguente riperfusione. Poiché i metodi per tMCAo evolvono, l&#39;uso più recente di filamenti silicone rivestite ridurre ulteriormente il rischio di emorragia subaracnoidea rispetto ad altri modelli 9,10 &lt;/ Sup&gt; e migliorare l&#39;affidabilità, anche se purtroppo tMCAo produce spesso una grande variazione dei volumi di infarto. 11-13 La maggior parte di questi studi delineano regioni infarto in sezioni di cervello coronali con la colorazione 2,3,5- trifeniltetrazolio cloruro (TTC), considerato un gold standard per la quantificazione infarto, perché è un modo semplice e poco costoso per produrre vivide, risultati replicabili. TTC serve come substrato delle deidrogenasi presenti nei mitocondri. Quando fettine cerebrali sono esposti alla soluzione TTC, TTC è selettivamente preso in cellule viventi in cui il suo prodotto di riduzione non solubile, formazano, precipita ad un colore rosso intenso nei mitocondri vitali. A causa della disfunzione mitocondriale nel tessuto ischemico, questo tessuto rimane bianca, consentendo la differenziazione dei tessuti danneggiati e sani. 14 RHP riduce anche perturbazione BBB nell&#39;emisfero ischemico. 6 Pertanto, il duplice quantificazione dell&#39;integrità BBB all&#39;interno dello stesso bpiogge il volume dell&#39;infarto-based TTC determinazioni 15 potrebbe fornire informazioni utili sul pieno efficacia di protezione endogena, e potenziali relazioni causali tra interruzione BBB e infarto negli animali non trattati e trattati. L&#39;afflusso di sangue periferico attraverso un BBB perturbato, secondaria a ictus, aumenta popolazioni leucocitarie, citochine pro-infiammatorie, lo stress ossidativo, vasogenico e trasformazione emorragica nell&#39;emisfero ischemico, in ultima analisi, aumentando i tassi di infezione e mortalità nei pazienti con ictus ischemico . 16,17 Un metodo comune per misurare BBB perturbazione nei modelli animali è attraverso la quantificazione del blu di Evans (EB) perdita di colorante nel cervello. 15,18-21 EB si lega selettivamente all&#39;albumina sierica, una proteina globulare (PM = 65 kDa) che non attraversa la BBB negli animali illesi. 22 A seguito di ictus ischemico, EB infiltra il cervello, e fluorescenza a 620 nm, permettendo per la misurazione della densità ottica within parenchima feriti perfuso. 22 La densità ottica è direttamente proporzionale alla permeabilità della BBB quando EB è stato lavato fuori della vascolarizzazione corticale post mortem da transcardiac perfusione. Con la trasformazione immediata di cervelli TTC-macchiati negli animali con la somministrazione EB, sia il volume dell&#39;infarto e BBB disagi possono essere efficacemente quantificati. Va notato, tuttavia, che danno neuronale e BBB perturbazione non sono processi concomitanti nel cervello post-ictus, 23,24 così la selezione del tempo di sacrificio è una considerazione importante. Il protocollo che segue i dettagli il metodo RHP, il metodo tMCAo per indurre una occlusione arteriosa temporaneo che modelli di mezza occlusioni dell&#39;arteria cerebrale nei pazienti umani, ei metodi istologici doppi per la determinazione neurali e vascolari endpoint lesioni ictus. TTC misura morte cellulare e danni ai tessuti cumulativo, permettendo la quantificazione di un infarto vol generaleume, mentre EB prevede la quantificazione del danno emisferica BBB.

<table border="0" cellpadding="0" cellspacing="0" width="830">
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			<td height="42" style="height:42px;width:249px;">Material/ Equipment</td>
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			<td style="width:127px;">Specialty order</td>
			<td style="width:283px;">Four flowmeters are attached to 6.0 mm flexible PVC tubing which connects to the inlet port on each induction chamber with a plastic female connector. These flowmeters are bolted to a 6.5&#34; x 1&#34; x 1&#34; metal bar. This metal bar is bolted to a MI-246-P pressure gauge with a DISS outlet. This pressure gauge and flowmeter equipment can be attached to each new gas cylinder with a wrench.</td>
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			<td style="width:283px;">Other surgical microscopes may be used.&#160;</td>
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			<td height="100" style="height:100px;width:249px;">Kent Scientific Right Temperature CODA</td>
			<td style="width:171px;">Kent Scientific Corporation</td>
			<td style="width:127px;">Discontinued</td>
			<td style="width:283px;">Recommended replacement is PhysioSuite with RightTemp Temperature Monitoring and Homeothermic Control (Kent Scientific, #PS-RT).</td>
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			<td height="60" style="height:60px;width:249px;">Hovabator Incubator</td>
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			<td style="width:127px;">2362-E</td>
			<td style="width:283px;">Our model is the 2362N. 2362E is a later model and includes an electronic thermostat.&#160;</td>
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			<td height="120" style="height:120px;width:249px;">V010 Anesthesia system&#160;</td>
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			<td style="width:283px;">Includes: ten foot high-pressure oxygen hose, frame, flowmeter, oxygen flush assembly, vaporizer, breathing circuit, chamber, nosecones, waste gas evacuation tubing and two VapoGuard filters</td>
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			<td style="width:171px;">Multiple sellers&#160;</td>
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			<td style="width:127px;">Specialty order</td>
			<td style="width:283px;">Filaments are silicone coated at Washington Univeristy and provided to UTSW facilities for a fee.&#160;</td>
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			<td height="20" style="height:20px;width:249px;">Evans Blue</td>
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			<td style="width:127px;">WHA1001150</td>
			<td style="width:283px;">150 mm, circles, Grade 1&#160;</td>
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			<td style="width:283px;">2.5&#34; diameter</td>
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			<td style="width:171px;">Fisher Scientific</td>
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			<td style="width:283px;"></td>
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			<td height="80" style="height:80px;width:249px;">Water Bath</td>
			<td style="width:171px;">Multiple sellers&#160;</td>
			<td style="width:127px;">Catalog number not available&#160;</td>
			<td style="width:283px;">Scintillation tubes with TTC may be manually held under running warm water as an alternative to the water bath.</td>
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		<tr height="40">
			<td height="40" style="height:40px;width:249px;">Styrofoam board</td>
			<td style="width:171px;">Multiple sellers&#160;</td>
			<td style="width:127px;">Catalog number not available&#160;</td>
			<td style="width:283px;"></td>
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		<tr height="20">
			<td height="20" style="height:20px;width:249px;">Large Syringe Kit</td>
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		<tr height="20">
			<td height="20" style="height:20px;width:249px;">60 cc syringe</td>
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		<tr height="40">
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			<td style="width:283px;"></td>
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		<tr height="40">
			<td height="40" style="height:40px;width:249px;">0.21 mm stainless steel blades, 25 pk</td>
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			<td style="width:127px;">Catalog number not available&#160;</td>
			<td style="width:283px;">Reusable cryostat blades are an inexpensive alternative.</td>
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		<tr height="40">
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			<td style="width:171px;">Fisher Scientific</td>
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			<td style="width:171px;">Multiple sellers&#160;</td>
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			<td style="width:283px;">Other commercial scanners are suitable for this step in the protocol.</td>
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			<td height="40" style="height:40px;width:249px;">ImageJ&#160;</td>
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			<td height="20" style="height:20px;width:249px;">Analytical Balance</td>
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			<td height="40" style="height:40px;width:249px;">1.7 mL microcentrifuge tubes (Eppendorfs)</td>
			<td style="width:171px;">Denville Scientific&#160;</td>
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			<td style="width:283px;"></td>
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			<td height="20" style="height:20px;width:249px;">Formamide</td>
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</table>

quantification of neurovascular protection following repetitive hypoxic preconditioning and transient middle cerebral artery occlusion in mice

Modelli animali sperimentali di ictus sono strumenti preziosi per la comprensione ictus patologia e sviluppare strategie di cura più efficaci. Un protocollo 2 settimane per ripetitivo precondizionamento ipossico (RHP) induce una protezione a lungo termine contro il sistema nervoso (CNS) lesione centrale in un modello murino di ictus ischemico focale. RHP consiste 9 esposizioni stocastici all&#39;ipossia che variano sia in durata (2 o 4 ore) e l&#39;intensità (8% e 11% O 2). RHP riduce volumi infarto, barriera emato-encefalica (BBB) ​​rottura, e la risposta infiammatoria post-ictus per settimane dopo l&#39;ultima esposizione all&#39;ipossia, suggerendo una induzione a lungo termine di un fenotipo CNS-protettivo endogeno. La metodologia per il duplice quantificazione del volume dell&#39;infarto e BBB perturbazione è efficace nel valutare la protezione neurovascolare nei topi con RHP o altri neuroprotectants putativi. Maschio adulto topi Swiss Webster sono stati condizionati da RHP o esposizioni di durata equivalente al 21% O <sub&gt; 2 (aria ambiente). A 60 min transitoria occlusione dell&#39;arteria cerebrale media (tMCAo) è stata indotta 2 settimane dopo l&#39;ultima esposizione ipossica. Sia l&#39;occlusione e riperfusione sono stati confermati da transcranico laser Doppler flussimetria. Ventidue ore dopo riperfusione, Blu di Evans (EB) è stato per via endovenosa somministrato attraverso una iniezione coda vena. 2 ore più tardi, gli animali sono stati sacrificati per sezioni di overdose e di cervello isoflurano sono stati colorati con 2,3,5- trifeniltetrazolio cloruro (TTC). Volumi infarti sono stati poi quantificati. Avanti, EB è stato estratto dal tessuto oltre 48 ore per determinare BBB perturbazione dopo tMCAo. In sintesi, RHP è un semplice protocollo che può essere replicato, con un costo minimo, per indurre a lungo termine endogeno protezione neurovascolare da un infortunio ictus nei topi, con il potenziale traslazionale per altri stati di malattia pro-infiammatorie CNS-based e sistemici.

Questo studio ha incluso 25 topi maschi Swiss Webster che erano 10 settimane di età all&#39;inizio di randomizzazione in RHP (n = 10) o il 21% O 2 (n = 15) gruppi. Due settimane dopo l&#39;esposizione finale RHP, sono stati eseguiti interventi chirurgici, con i gruppi in cieco e controbilanciato tra i giorni. Dopo tMCAo, 1 topo morto durante il recupero post-operatorio e 1 mouse è stato escluso dallo studio perché non soddisfa il criterio di riperfusione CBF. Entrambi i mouse sono stati esclusi dal gruppo ...

Watch this Scientific Journal Video about Quantification of Neurovascular Protection Following Repetitive Hypoxic Preconditioning and Transient Middle Cerebral Artery Occlusion in Mice at JoVE.com

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

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.

Quantificazione della Protezione Neurovascular seguito ripetitivo ipossico precondizionamento e transitoria occlusione dell&#39;arteria cerebrale media nei topi

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

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13.6K Views.  University of Texas Southwestern Medical Center. 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.

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

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.

Corsa di modellazione in Mouse - Medio occlusione dell&#39;arteria cerebrale con il Modello Filament

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

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Mouse Model of Middle Cerebral Artery Occlusion

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 brain (ischemic stroke) 2. Since most ischemic strokes (~80%) occur in the territory of middle cerebral artery (MCA) 3, many animal stroke models that have been developed have focused on this artery. The intraluminal monofilament model of middle cerebral artery occlusion (MCAO) involves the insertion of a surgical filament into the external carotid artery and threading it forward into the internal carotid artery (ICA) until the tip occludes the origin of the MCA, resulting in a cessation of blood flow and subsequent brain infarction in the MCA territory 4. The technique can be used to model permanent or transient occlusion 5. If the suture is removed after a certain interval (30 min, 1 h, or 2 h), reperfusion is achieved (transient MCAO); if the filament is left in place (24 h) the procedure is suitable as a model of permanent MCAO. This technique does not require craniectomy, a neurosurgical procedure to remove a portion of skull, which may affect intracranial pressure and temperature 6. It has become the most frequently used method to mimic permanent and transient focal cerebral ischemia in rats and mice 7,8. To evaluate the extent of cerebral infarction, we stain brain slices with 2,3,5-triphenyltetrazolium chloride (TTC) to identify ischemic brain tissue 9. In this video, we demonstrate the MCAO method and the determination of infarct size by TTC staining.

We demonstrate in the video a method for producing a middle cerebral artery occlusion in adult mice using an intraluminal monofilament. We also show how to evaluate the extent of cerebral infarction by 2,3,5-triphenyltetrazolium chloride (TTC) staining.

Modello murino di Mezzo occlusione dell&#39;arteria cerebrale

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 ...

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.

Intraluminali occlusione dell&#39;arteria cerebrale media (MCAO) Modello per l&#39;ictus ischemico con la guida flussimetria laser Doppler in topi

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 ...

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.

L&#39;endotelina-1 indotta cerebrale media occlusione dell&#39;arteria modello per l&#39;ictus ischemico con guida laser flussimetria Doppler 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 ...

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.

Utilizzando una finestra craniale per visualizzare l&#39;arteria cerebrale media Durante endotelina-1 indotta da occlusione dell&#39;arteria cerebrale 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 ottimizzato per il monitoraggio perfusione cerebrale nel modello Rat Stroke of intraluminale occlusione dell&#39;arteria cerebrale media

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

Modeling Stroke in Mice: Permanent Coagulation of the Distal Middle Cerebral Artery

Stroke is the third most common cause of death and a main cause of acquired adult disability in developed countries. Only very limited therapeutical options are available for a small proportion of stroke patients in the acute phase. Current research is intensively searching for novel therapeutic strategies and is increasingly focusing on the sub-acute and chronic phase after stroke because more patients might be eligible for therapeutic interventions in a prolonged time window. These delayed mechanisms include important pathophysiological pathways such as post-stroke inflammation, angiogenesis, neuronal plasticity and regeneration. In order to analyze these mechanisms and to subsequently evaluate novel drug targets, experimental stroke models with clinical relevance, low mortality and high reproducibility are sought after. Moreover, mice are the smallest mammals in which a focal stroke lesion can be induced and for which a broad spectrum of transgenic models are available. Therefore, we describe here the mouse model of transcranial, permanent coagulation of the middle cerebral artery via electrocoagulation distal of the lenticulostriatal arteries, the so-called &#8220;coagulation model&#8221;. The resulting infarct in this model is located mainly in the cortex; the relative infarct volume in relation to brain size corresponds to the majority of human strokes. Moreover, the model fulfills the above-mentioned criteria of reproducibility and low mortality. In this video we demonstrate the surgical methods of stroke induction in the &#8220;coagulation model&#8221; and report histological and functional analysis tools.

Various murine models of middle cerebral artery occlusion (MCAO) are widely used in experimental brain research. Here, we demonstrate the model of transcranial permanent distal MCAO which produces consistent cortical infarction of a size corresponding to damage imposed by the majority of human ischemic strokes.

Corsa di modellazione in Mouse: Coagulazione permanente dell&#39;arteria cerebrale media distale

Stroke is the third most common cause of death and a main cause of acquired adult disability in developed countries. Only very limited therapeutical ...

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.

Embolic occlusione dell&#39;arteria cerebrale media (MCAO) per l&#39;ictus ischemico con omologhi coaguli di sangue nei ratti

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

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.

Approccio chirurgico per occlusione dell&#39;arteria cerebrale media e riperfusione indotta ictus nei topi

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.

Transient Medio occlusione dell&#39;arteria cerebrale Modello di Stroke neonatale nei ratti 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 ...