Vorremmo ringraziare la Fondazione Chirurgia Toracica di Ricerca e Formazione per il loro sostegno finanziario di questo progetto.

1. Preoperatoria Preparazione e Anestesia <ol><li> Assicurarsi di osservare la tecnica sterile durante tutta la procedura. Disporre tutti gli strumenti. </li><li> Accendere il letto controllo della temperatura prima dell&#39;induzione anestetica modo che possa riscaldare a temperatura appropriata (36,5 ° C). Accendere il monitor perfusione laser Doppler in modo che possa avviarsi durante l&#39;induzione. </li><li> Posizionare il mouse nella camera di induzione. <ol><li> Monitorare attentamente la frequenza respiratoria del mouse durante l&#39;induzione. </li><li> Non appena la frequenza respiratoria è rallentato visivamente, rimuovere il mouse dalla camera di induzione. </li><li> Eseguire pizzico punta a valutare l&#39;adeguatezza di anestetico. </li></ol></li><li> Con il mouse adeguatamente anestetizzato, mouse posto in posizione supina. </li><li> Inserire la faccia nel cono e fissare tutte le estremità al tavolo di riscaldamento. <ol><li> Prestare particolare attenzione per garantire che le estremità sono fissate in posizione anatomica, senza deviatisu un lato. Se il mouse viene posizionato in modo improprio, è difficile evitare interna recisione arteria toracica durante sternotomia. </li></ol></li><li> Utilizzando tagliaunghie o disponibile in commercio crema depilatoria, eliminare i peli dal torace linea mediana e inferiore sinistro superficie ventrale estremità. <ol><li> Se si utilizza crema depilatoria, evitare di lasciare la crema sul posto per più di 30 secondi, possono verificarsi ustioni da alcali. </li></ol></li><li> Titolare volatili concentrazione vaporizzatore anestetico per mantenere l&#39;anestesia adeguata. <ol><li> Frazioni vaporizzatore attesi sono compresi tra 1-5% con isoflurano con alto flusso O 2. </li><li> Volatile concentrazione vaporizzatore di anestetico deve essere titolata per mantenere l&#39;anestesia durante la stimolazione chirurgica pur mantenendo la respirazione spontanea. </li></ol></li></ol> 2. Rettale Sonda Laser Doppler Placement <ol><li> Inserire sonda rettale lubrificato nel retto del mouse. Fissare in atto per operrativo letto. </li><li> Regolare il letto riscaldamento per una temperatura rettale obiettivo di 36,5 ° C. </li><li> Fai la piccola incisione sopra arteria femorale del mouse e sezionare la pelle dal tessuto sottocutaneo. </li><li> Inserire la sonda Doppler laser su arteria femorale. </li><li> Regolare la posizione della sonda finché il monitor perfusione registra maggiore di 800 unità di perfusione. <ol><li> Sonda fermamente sicuro al suo posto. Sonde impropriamente depositati possono avere misure falsamente bassa perfusione. </li></ol></li></ol> 3. Dissezione aortica di Arch / Arteria succlavia <ol><li> Effettuare una incisione cutanea 2 centimetri al di sopra della sternale e delicatamente sezionare la pelle dal tessuto sottocutaneo. </li><li> Sezionare la ghiandola sottomandibolare libero. <ol><li> Se si verifica sanguinamento, una leggera pressione può essere applicato con un batuffolo di cotone. </li><li> Dividere la ghiandola sottomandibolare tramite linea mediana nel piano avascolare. </li></ol></li><li> Sollevare delicatamente sterno con una pinza e con il SCISSRUP fanno 1 centimetro sternotomia mediana attraverso la linea mediana dello sterno. Qualsiasi deviazione dalla linea mediana può causare emorragia interna dell&#39;arteria mammaria che sarà difficile da controllare. </li><li> Mettere 5-0 suture retrazione su ogni lato al bordo dello sterno e ritrarre sterno lateralmente garantire punti di sutura al letto di funzionamento. Evitare di posizionare suture retrazione troppo lateralmente per evitare pneumotorace. </li><li> Utilizzando smussa muscoli cinghia libera lungo trachea. Il muscolo cinghia di sinistra può essere diviso con le forbici per migliorare l&#39;esposizione. </li><li> Sezionare liberare il timo dal tessuto circostante. Continuare smussa fino a quando le grandi navi sono visualizzati. Prestare la massima attenzione per evitare l&#39;ingresso nello spazio pleurico. </li><li> Posizionare i morsetti vascolari su arco aortico e all&#39;arteria succlavia sinistra. </li><li> Verificare il flusso distale è opportunamente interrotto. Questo sarà visto come una riduzione&gt; 90% in unità di perfusione. <ol><li> Continua occlusione per desirosso per 4-8 min. </li></ol></li><li> Rimuovere il morsetto vascolare e verificare emostasi prima della chiusura del torace. </li></ol> 4. Chiusura della sternotomia e pelle <ol><li> Rimuovere la sutura svincolo sul lato sinistro del mouse. </li><li> Chiudere la sternotomia con il giusto distacco sutura. <ol><li> Una singola sutura sternale (tramite il punto di svincolo precedentemente posizionato) è adeguata per la chiusura sternale. Posizionamento di un altro punto è inutile e aumenta i rischi di pneumotorace e di emorragia. </li></ol></li><li> Chiudere la pelle con l&#39;esecuzione 5-0 punti. </li></ol> 5. Valutazione Recupero e postoperatoria <ol><li> Trasferire il mouse per gabbia di recupero. Gabbia deve essere posto su una piastra elettrica per aumentare la temperatura della camera di recupero e ridurre la perdita di calore verso l&#39;ambiente. </li><li> Seguire da vicino il mouse per i segni distress respiratorio o attività convulsiva. Somministrare analgesia secondo le linee guida dell&#39;istituzione. Euthatopi scere immediatamente se si osservano sequestro o distress respiratorio. <ol><li> CO eutanasia a 2 camere è il nostro metodo preferito. Dislocazione cervicale è un&#39;altra opzione se CO 2 non è disponibile. </li><li> Recupero totale può essere prevedibile in 1-2 ore, a seconda della lunghezza di anestetico volatile e concentrazione usata. </li></ol></li><li> Riportare il mouse per gabbia normale. Disporre il cibo e posto acqua sul pavimento della gabbia. </li><li> Valutare lo stato neurologico, ad intervalli di 12 h con Basso mouse Scale for Locomotion 8. </li></ol>

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Gli autori dichiarano interessi finanziari concorrenti.

Paraplegia secondaria di midollo spinale ischemia riperfusione è il risultato di un complesso di patologie poco conosciute 9. Mentre questo è più frequente dopo chirurgia dell&#39;aorta toraco, una varietà di altri insulti come dissezioni aortiche, traumi, fenomeni embolici, vasculite, ipotensione sistemica e 10 può causare paraplegia. Per ottenere una maggiore comprensione di questo pregiudizio e fornire obiettivi futuri per eliminare questo pregiudizio, i modelli animali sono diventati una n...

Arti inferiori paralisi continua a complicare interventi toraco-addominali. La lesione, noto come midollo spinale danno da ischemia-riperfusione (SCIR), causando paralisi in fino al 20% dei pazienti ad alto rischio 1. Aggiunte chirurgiche come la sinistra di bypass al cuore, lombari scarichi fluidi cerbrospinal, ipotermia e arresto circolatorio dell&#39;arteria intercostale reimpianto hanno ridotto l&#39;incidenza di questa complicanza 2, tuttavia, troppi pazienti continuano a essere colpiti. Lesioni Clinicamente, ischemia del midollo spinale e la riperfusione è visto come immediato o successivo paralisi dopo l&#39;intervento 3. Tuttavia, la nostra comprensione di questo pregiudizio è stato soffocato dalla mancanza di dettagli meccanicistica. Come risultato, sono disponibili per attenuare il pregiudizio conclamata alcune opzioni. Abbiamo così arruolato un animale piccolo, murino, modello di ischemia del midollo spinale, e danno da riperfusione ameglio caratterizzare la sua patogenesi. La maggior parte degli studi fino ad oggi hanno utilizzato modelli animali più grandi per caratterizzare questa lesione, vale a dire 4 ratto, coniglio 5, e maiale 6 modelli. Tuttavia, questi sono limitati dal loro costo, la complessità riproducibilità variabile, e, soprattutto, la mancanza di tecniche disponibili per la manipolazione genetica. Il più affidabile di questi modelli animali pubblicati coinvolge sottorenale bloccaggio trasversale dell&#39;aorta addominale in conigli. Tuttavia, anteriori umano neuroni spinali spesso derivano il loro apporto vascolare da rami più prossimali 7. Variabile anatomia vascolare del midollo spinale in questi modelli aggiunge alla difficoltà di transizione loro risultati in uso clinico. Questo manoscritto presenta un modello di paraplegia immediato o ritardato seguente toracica occlusione aortica che è clinicamente rilevante e facile da utilizzare. L&#39;esposizione dell&#39;arco aortico via mini sternotola mia è meno invasivo e può suscitare risultati altamente riproducibili con la morbilità e la mortalità minima. Mentre questo modello in non senza difficoltà e sfumature tecniche, questi possono essere superati con un&#39;attenta dissezione e la manipolazione dei tessuti per produrre un modello di arto posteriore paralisi che può essere facilmente implementato.

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			<td height="21" style="height:21px;width:216px;">VMS Anesthesia Machine</td>
			<td style="width:247px;">MDS Matrx</td>
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			<td style="width:167px;"></td>
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			<td height="21" style="height:21px;width:216px;">Isoflurane</td>
			<td style="width:247px;">Vet One</td>
			<td style="width:119px;">13985-528-60</td>
			<td>2.0% through nose cone&#160;</td>
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			<td height="21" style="height:21px;width:216px;">Laser Doppler Monitor</td>
			<td style="width:247px;">Moor Instruments</td>
			<td style="width:119px;">VMS-LDF1</td>
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			<td height="21" style="height:21px;width:216px;">5-0 Suture, Polyester</td>
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			<td>Forceps, needle holder</td>
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reproducable paraplegia by thoracic aortic occlusion in a murine model of spinal cord ischemia-reperfusion

Sfondo Arti inferiori paralisi continua a complicare interventi aortici. La mancanza di comprensione della patologia sottostante ha ostacolato progressi per diminuire il verificarsi questa lesione. L&#39;attuale modello dimostra riproducibile paralisi degli arti inferiori in seguito toracica occlusione aortica. Metodi Adulto topi C57BL6 sesso maschile sono stati anestetizzati con isoflurano. Attraverso un&#39;incisione cervicosternal l&#39;aorta è stato esposto. I aorta discendente e succlavia sinistra arterie toraciche sono stati identificati senza l&#39;ingresso nello spazio pleurico. Scheletrizzazione di queste arterie è stata seguita da chiusura immediata (Sham) o occlusione per 4 min (ischemia moderata) o 8 min (ischemia prolungata). La sternotomia e la pelle sono stati chiusi e il mouse è stato trasferito a letto riscaldamento per il recupero. Dopo il recupero, l&#39;analisi funzionale è stata ottenuta a intervalli di 12 ore fino a 48 ore. Risultati I topi sottoposti a chirurgia simulata non hanno mostrato deficit degli arti posteriori osservabile. I topi sottoposti a ischemia moderato per 4 min avevano deficit funzionale minimo a 12 ore seguita da progressione alla paralisi completa in 48 ore. I topi sottoposti a ischemia prolungata avevano una paralisi immediato con nessun movimento arti posteriori osservabile in qualsiasi momento nel periodo postoperatorio. Non c&#39;era intraoperatoria osservati o mortalità post operatoria. Conclusione Riproducibile inferiore paralisi degli arti immediati o differiti può essere realizzato in un modello murino. Inoltre, utilizzando una sternotomia mediana e attenta dissezione, alti tassi di sopravvivenza e la riproducibilità può essere raggiunto.

Topi subito un intervento chirurgico sham (n = 3) o occlusione aortica per 4 (n = 3) per 8 min (n = 3). Topi dopo l&#39;intervento sono stati classificati con il punteggio Basso Mouse (Figura 1). I topi sottoposti a chirurgia simulata non avevano deficit funzionali osservabili in qualsiasi momento dopo l&#39;intervento. I topi sottoposti a ischemia moderata (4 min) avevano vicino normale funzione arti posteriori a 12 ore con il declino funzionale progressivo alla paralisi completa per 48 ore. Mice in gr...

Watch this Scientific Journal Video about Reproducable Paraplegia by Thoracic Aortic Occlusion in a Murine Model of Spinal Cord Ischemia-reperfusion at JoVE.com

Reproducable Paraplegia by Thoracic Aortic Occlusion in a Murine Model of Spinal Cord Ischemia-reperfusion

La mancanza di comprensione meccanicistica del midollo spinale ischemia-riperfusione ha impedito ulteriori aggiunte per evitare paraplegia seguenti operazioni aortica ad alto rischio. Pertanto, lo sviluppo di modelli animali è imperativo. Questo manoscritto dimostra riproducibile paralisi degli arti inferiori in seguito toracica occlusione aortica in un modello murino.

Riproducibile Paraplegia da Toracica aortica occlusione in un modello murino di Spinal Cord ischemia-riperfusione

Background
Lower extremity paralysis continues to complicate aortic interventions. The lack of understanding of the underlying pathology has hindered ...

reproducable-paraplegia-thoracic-aortic-occlusion-murine-model-spinal

Research

JoVE Journal

Medicine

11.9K Views.  University of Colorado.  La mancanza di comprensione meccanicistica del midollo spinale ischemia-riperfusione ha impedito ulteriori aggiunte per evitare paraplegia seguenti operazioni aortica ad alto rischio. Pertanto, lo sviluppo di modelli animali è imperativo. Questo manoscritto dimostra riproducibile paralisi degli arti inferiori in seguito toracica occlusione aortica in un modello murino. 

Video: Reproducable Paraplegia by Thoracic Aortic Occlusion in a Murine Model of Spinal Cord Ischemia-reperfusion

Acute and Chronic Tactile Sensory Testing after Spinal Cord Injury in Rats

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory testing in rat SCI models is needed. However, until recently, no single testing approach had been validated for SCI so that standardized methods have not been implemented across labs. Additionally, available testing methods could not be implemented acutely or when severe motor impairments existed, preventing studies of the development of SCI-induced allodynia3. Here we present two validated sensory testing methods using von Frey Hair (VFH) monofilaments which quantify changes in tactile sensory thresholds after SCI4-5. One test is the well-established Up-Down test which demonstrates high sensitivity and specificity across different SCI severities when tested chronically5. The other test is a newly-developed dorsal VFH test that can be applied acutely after SCI when allodynia develops, prior to motor recovery4-5. Each VFH monofilament applies a calibrated force when touched to the skin of the hind paw until it bends. In the up-down method, alternating VFHs of higher or lower forces are used on the plantar L5 dermatome to delineate flexor withdrawal thresholds. Successively higher forces are applied until withdrawal occurs then lower force VFHs are used until withdrawal ceases. The tactile threshold reflects the force required to elicit withdrawal in 50% of the stimuli. For the new test, each VFH is applied to the dorsal L5 dermatome of the paw while the rat is supported by the examiner. The VFH stimulation occurs in ascending order of force until at least 2 of 3 applications at a given force produces paw withdrawal. Tactile sensory threshold is the lowest force to elicit withdrawal 66% of the time. Acclimation, testing and scoring procedures are described. Aberrant trials that require a retest and typical trials are defined. Animal use was approved by Ohio State University Animal Care and Use Committee.

We describe two tactile sensory testing methods for acute or chronic periods of spinal cord injury in rats. These validated procedures can detect the development and maintenance of allodynia-like sensations.

Acuta e Cronica test sensoriale tattile dopo lesione del midollo spinale in ratti

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory ...

Ricerca

Medicina

A Contusion Model of Severe Spinal Cord Injury in Rats

The translational potential of novel treatments should be investigated in severe spinal cord injury (SCI) contusion models. A detailed methodology is described to obtain a consistent model of severe SCI. Use of a stereotactic frame and computer controlled impactor allows for creation of reproducible injury. Hypothermia and urinary tract infection pose significant challenges in the post-operative period. Careful monitoring of animals with daily weight recording and bladder expression allows for early detection of post-operative complications. The functional results of this contusion model are equivalent to transection models. The contusion model can be utilized to evaluate the efficacy of both neuroprotective and neuroregenerative approaches.

A contusion model of severe spinal cord injury is described. Detailed pre-operative, operative and post-operative steps are described to obtain a consistent model.

Un modello Contusione di gravi lesioni del midollo spinale nei ratti

The translational potential of novel treatments should be investigated in severe spinal cord injury (SCI) contusion models. A detailed methodology is ...

A Murine Model of Cervical Spinal Cord Injury to Study Post-lesional Respiratory Neuroplasticity

A cervical spinal cord injury induces permanent paralysis, and often leads to respiratory distress. To date, no efficient therapeutics have been developed to improve/ameliorate the respiratory failure following high cervical spinal cord injury (SCI). Here we propose a murine pre-clinical model of high SCI at the cervical 2 (C2) metameric level to study diverse post-lesional respiratory neuroplasticity. The technique consists of a surgical partial injury at the C2 level, which will induce a hemiparalysis of the diaphragm due to a deafferentation of the phrenic motoneurons from the respiratory centers located in the brainstem. The contralateral side of the injury remains intact and allows the animal recovery. Unlike other SCIs which affect the locomotor function (at the thoracic and lumbar level), the respiratory function does not require animal motivation and the quantification of the deficit/recovery can be easily performed (diaphragm and phrenic nerve recordings, whole body ventilation). This pre-clinical C2 SCI model is a powerful, useful, and reliable pre-clinical model to study various respiratory and non-respiratory neuroplasticity events at different levels (molecular to physiology) and to test diverse putative therapeutic strategies which might improve the respiration in SCI patients.

Respiratory failure is the leading cause of death following a cervical spinal cord injury. Having a reproducible, quantifiable, and reliable pre-clinical animal model of respiratory failure induced by a partial cervical injury will help to understand the subsequent respiratory and non-respiratory neuroplasticity and allow testing putative repair strategies.

Un modello murino di cervicale lesioni del midollo spinale per studiare post-lesionale respiratoria neuroplasticità

A cervical spinal cord injury induces permanent paralysis, and often leads to respiratory distress. To date, no efficient therapeutics have been developed ...

A Murine Model of Myocardial Ischemia-reperfusion Injury through Ligation of the Left Anterior Descending Artery

Acute or chronic myocardial infarction (MI) are cardiovascular events resulting in high morbidity and mortality. Establishing the pathological mechanisms at work during MI and developing effective therapeutic approaches requires methodology to reproducibly simulate the clinical incidence and reflect the pathophysiological changes associated with MI. Here, we describe a surgical method to induce MI in mouse models that can be used for short-term ischemia-reperfusion (I/R) injury as well as permanent ligation. The major advantage of this method is to facilitate location of the left anterior descending artery (LAD) to allow for accurate ligation of this artery to induce ischemia in the left ventricle of the mouse heart. Accurate positioning of the ligature on the LAD increases reproducibility of infarct size and thus produces more reliable results. Greater precision in placement of the ligature will improve the standard surgical approaches to simulate MI in mice, thus reducing the number of experimental animals necessary for statistically relevant studies and improving our understanding of the mechanisms producing cardiac dysfunction following MI. This mouse model of MI is also useful for the preclinical testing of treatments targeting myocardial damage following MI.

We introduce a surgical method to induce experimental ischemia/reperfusion (I/R) injury to simulate myocardial infarction (MI) in mouse models that allows for more clarity in positioning of the ligation on the left anterior descending artery (LAD) to increase the reproducibility of MI experiments in mice.

Un modello murino di ischemia miocardica e riperfusione lesioni da legatura della arteria discendente anteriore sinistra

Acute or chronic myocardial infarction (MI) are cardiovascular events resulting in high morbidity and mortality. Establishing the pathological mechanisms ...

A Radio-telemetric System to Monitor Cardiovascular Function in Rats with Spinal Cord Transection and Embryonic Neural Stem Cell Grafts

High thoracic or cervical spinal cord injury (SCI) can lead to cardiovascular dysfunction. To monitor cardiovascular parameters, we implanted a catheter connected to a radio transmitter into the femoral artery of rats that underwent a T4 spinal cord transection with or without grafting of embryonic brainstem-derived neural stem cells expressing green fluorescent protein. Compared to other methods such as cannula insertion or tail-cuff, telemetry is advantageous to continuously monitor blood pressure and heart rate in freely moving animals. It is also capable of long term multiple data acquisitions. In spinal cord injured rats, basal cardiovascular data under unrestrained condition and autonomic dysreflexia in response to colorectal distension were successfully recorded. In addition, cardiovascular parameters before and after SCI can be compared in the same rat if a transmitter is implanted before a spinal cord transection. One limitation of the described telemetry procedure is that implantation in the femoral artery may influence the blood supply to the ipsilateral hindlimb.

We present a protocol for using a radio-telemetric system to record cardiovascular parameters in T4 spinal cord transected rats eight weeks after embryonic brainstem neural stem cell grafting into the lesion site. Telemetry is an advanced technique to accurately evaluate cardiovascular function in conscious freely moving spinal cord injured rats.

Un sistema radio-telemetria per monitorare la funzionalità cardiovascolare in ratti con midollo spinale e Transection embrionali staminali neurali Innesti cellulari

High thoracic or cervical spinal cord injury (SCI) can lead to cardiovascular dysfunction. To monitor cardiovascular parameters, we implanted a catheter ...

Murine Model of Intestinal Ischemia-reperfusion Injury

Intestinal ischemia is a life-threatening condition associated with a broad range of clinical conditions including atherosclerosis, thrombosis, hypotension, necrotizing enterocolitis, bowel transplantation, trauma and chronic inflammation. Intestinal ischemia-reperfusion (IR) injury is a consequence of acute mesenteric ischemia, caused by inadequate blood flow through the mesenteric vessels, resulting in intestinal damage. Reperfusion following ischemia can further exacerbate damage of the intestine. The mechanisms of IR injury are complex and poorly understood. Therefore, experimental small animal models are critical for understanding the pathophysiology of IR injury and the development of novel therapies.
Here we describe a mouse model of acute intestinal IR injury that provides reproducible injury of the small intestine without mortality. This is achieved by inducing ischemia in the region of the distal ileum by temporally occluding the peripheral and terminal collateral branches of the superior mesenteric artery for 60 min using microvascular clips. Reperfusion for 1 hr, or 2 hr after injury results in reproducible injury of the intestine examined by histological analysis. Proper position of the microvascular clips is critical for the procedure. Therefore the video clip provides a detailed visual step-by-step description of this technique. This model of intestinal IR injury can be utilized to study the cellular and molecular mechanisms of injury and regeneration.

Here we describe the detailed procedure of intestinal ischemia-reperfusion in mice which results in reproducible injury without mortality to encourage the standardization of this technique across the field. This model of intestinal ischemia-reperfusion injury can be utilized to study the cellular and molecular mechanisms of injury and regeneration.

Modello murino di ischemia-riperfusione intestinale Injury

Intestinal ischemia is a life-threatening condition associated with a broad range of clinical conditions including atherosclerosis, thrombosis, ...

Reproducible Motor Deficit Following Aortic Occlusion in a Rat Model Of Spinal Cord Ischemia

Spinal cord ischemia is a fatal complication following thoracoabdominal aortic aneurysm surgery. Researchers can investigate the strategies for preventing and treating this complication using experimental models of spinal cord ischemia. The model described here demonstrates varying degrees of paraplegia that relate to the length of occlusion following thoracic aortic occlusion in a rat spinal cord ischemia model.
A 2-Fr. balloon-tipped catheter was advanced through the femoral artery into the descending thoracic aorta until the catheter tip was placed at the left subclavian artery in anesthetized male Sprague-Dawley rats. Spinal cord ischemia was induced by inflating the catheter balloon. After a set period of occlusion (9, 10, or 11 min), the balloon was deflated. Neurologic assessment was performed using the motor deficit index at 24 h after surgery, and the spinal cord was harvested for histopathological examination.
Rats that underwent 9 min of aortic occlusion showed mild and reversible motor impairment in the hind limb. Rats subjected to 10 min of aortic occlusion presented with moderate but reversible motor impairment. Rats subjected to 11 min of aortic occlusion displayed complete and persistent paralysis. The motor neurons in the spinal cord sections were more preserved in rats subjected to shorter duration of aortic occlusion.
Researchers can achieve a reproducible hind limb motor deficit following thoracic aortic occlusion using this spinal cord ischemia model.

This study demonstrates the technique to make a minimally invasive and easily reproducible model of spinal cord ischemia in rats. Various degrees of hind limb motor deficit can be produced by controlling the aortic occlusion time.

Deficit motore riproducibile a seguito dell&#39;occlusione aortica in un modello di ratto dell&#39;ischemia del midollo spinale

Spinal cord ischemia is a fatal complication following thoracoabdominal aortic aneurysm surgery. Researchers can investigate the strategies for preventing ...

Two-vessel Occlusion Mouse Model of Cerebral Ischemia-reperfusion

In this study, a middle cerebral artery (MCA) occlusion mouse model is employed to study cerebral ischemia-reperfusion. A reproducible and reliable mouse model is useful for investigating the pathophysiology of cerebral ischemia-reperfusion and determining potential therapeutic strategies for patients with stroke. Variations in the anatomy of the circle of Willis of C57BL/6 mice affects their infarct volume after cerebral-ischemia-induced injury. Studies have indicated that distal MCA occlusion (MCAO) can overcome this problem and result in a stable infarct size. In this study, we establish a two-vessel occlusion mouse model of cerebral ischemia-reperfusion through the interruption of the blood flow to the right MCA. We distally ligate the right MCA and right common carotid artery (CCA) and restore blood flow after a certain period of ischemia. This ischemia-reperfusion injury induces an infarct of stable size and a behavioral deficit. Peripheral immune cells infiltrate the ischemic brain within the 24 h infiltration period. Additionally, the neuronal loss in the cortical area is less for a longer reperfusion duration. Therefore, this two-vessel occlusion model is suitable for investigating the immune response and neuronal recovery during the reperfusion period after cerebral ischemia.

A mouse model of cerebral ischemia-reperfusion is established to investigate the pathophysiology of stroke. We distally ligate the right middle cerebral artery and right common carotid artery and restore blood flow after 10 or 40 min of ischemia.

Occlusione del vaso due Mouse modello di Ischemia-riperfusione cerebrale

In this study, a middle cerebral artery (MCA) occlusion mouse model is employed to study cerebral ischemia-reperfusion. A reproducible and reliable mouse ...

Evaluation of Coronary Flow Reserve After Myocardial Ischemia Reperfusion in Rats

Coronary artery disease is the leading cause of death worldwide. After an acute myocardial infarction, early and successful myocardial intervention via recanalization of the coronary artery is the most effective strategy for reducing the size of ischemic myocardium. The coronary microvasculature cannot be visualized and imaged&#160;in vivo, but there are several invasive and noninvasive techniques that can be used to assess parameters which depend directly on coronary microvascular function. The endothelial function after ischemia reperfusion can be assessed also at the level of the coronary circulation via the coronary flow reserve (CFR).&#160;In this study, peak velocity of left anterior descending (LAD) coronary arteries was measured in rats in vivo via Transthoracic Doppler Echocardiography during resting and stress challenge (induced by Dobutamine). A normal heart can increase its coronary blood flow up to four times above the resting values during stress induction. Following ischemia reperfusion, we found a significantly diminished CFR, which can be used as a marker of coronary microvascular dysfunction. CFR has opened a window on the importance of microvascular dysfunction and has been shown to predict cardiovascular risk independent of whether the severe obstructive disease is present.

Coronary flow reserve (CFR), is defined as the ratio of maximal coronary blood flow to the resting coronary blood flow. We present a protocol for evaluating CFR in rats via ultrasound, which offers the opportunity to predict cardiovascular risk factors in the absence of obstructive coronary disease.

Valutazione della riserva del flusso coronario dopo la miaocardia Ischemia Reperfusione nei ratti

Coronary artery disease is the leading cause of death worldwide. After an acute myocardial infarction, early and successful myocardial intervention via ...

Murine Surgical Model of Topical Elastase Induced Descending Thoracic Aortic Aneurysm

According to the Center for Disease Control, aortic aneurysms (AAs) were considered a leading cause of death in all races and both sexes from 1999-2016. An aneurysm forms as a result of progressive weakening and eventual dilation of the aorta, which can rupture or tear once it reaches a critical diameter. Aneurysms of the descending aorta in the chest, called descending thoracic aortic aneurysms (dTAA), make up a large proportion of aneurysm cases in the United States. Uncontained dTAA rupture is almost universally lethal, and elective repair has a high rate of morbidity and mortality. The purpose of our model is to study dTAA specifically, to elucidate the pathophysiology of dTAA and to search for molecular targets to halt the growth or reduce the size of dTAA. By having a murine model to study thoracic pathology precisely, targeted therapies can be developed to specifically test dTAA. The method is based on the placement of porcine pancreatic elastase (PPE) directly on the outer murine aortic wall after surgical exposure. This creates a destructive and inflammatory reaction, which weakens the aortic wall and allows for aneurysm formation over weeks to months. Though murine models possess limitations, our dTAA model produces robust aneurysms of predictable size. Furthermore, this model can be used to test genetic and pharmaceutical targets which may arrest dTAA growth or prevent rupture. In human patients, interventions such as these could help avoid aneurysm rupture, and difficult surgical intervention.

We describe a surgical protocol to consistently induce robust descending thoracic aortic aneurysms in mice. The procedure involves left thoracotomy, thoracic aorta exposure, and placement of a sponge soaked in porcine pancreatic elastase on the aortic wall.

Modello chirurgico murine dell'elastasi topica indotta decrescente all'aneurtica toracica

According to the Center for Disease Control, aortic aneurysms (AAs) were considered a leading cause of death in all races and both sexes from 1999-2016. ...