Name: electrolytic inferior vena cava model (eim) of venous thrombosis
Uploaded: 2011-07-12T13:00:00
Duration: 6 min 3 s
Description: Watch this Scientific Journal Video about Electrolytic Inferior Vena Cava Model EIM of Venous Thrombosis at JoVE.com

Soutenu par le NIH 1P01HL089407-01A1 (Lawrence, PI), des animaux de base A, NIH 1 K01 HL080962-01A2 (Myers, PI).

1. Procédures d&#39;anesthésie de la souris <ol><li> Les animaux sont retirés de leur cage et placé dans une chambre d&#39;induction anesthésique pré-opératoire pour l&#39;induction de gaz à 2% d&#39;isoflurane et 100% d&#39;oxygène à un débit de 0,5 litres par minute (vaporisateur contrôlée). </li><li> Les souris sont sous sédation dans la chambre de l&#39;induction anesthésique, retiré de la chambre et l&#39;abdomen ventral est rasée avec une tondeuse électrique, ou maintenu dans la chambre si une épilation des cheveux est utilisé (1 min). </li><li> Alors qu&#39;il était encore sous sédation, ils sont pesés, les yeux sont lubrifiés avec de la pommade ophtalmique stérile et, ensuite placé dans décubitus dorsal sur un dispositif de chauffage d&#39;eau chaude circulant sous anesthésie générale avec un cône de nez à l&#39;aide d&#39;isoflurane et de l&#39;oxygène. A ce point du taux d&#39;oxygène est réduit à 0,2 litres par minute. </li><li> L&#39;abdomen est pulvérisé avec une solution de chlorhexidine (diacétate de chlorhexidine est rapidement bacterialcidal et persistante) et essuyé avec une gaze stérile à trois reprises ou jusqu&#39;à ce que le site chirurgical est propre. </li></ol> 2. Souris micro-chirurgicales et les procédures de récupération <ol><li> Une incision médiane ventrale (2 cm) est faite avec des ciseaux iris à travers la peau et la paroi abdominale exposer l&#39;abdomen. Un 2x2 salines stériles trempées dans de la gaze est utilisée pour refléter les intestins à gauche de l&#39;animal. Un dispositif de retenue de la souris est mis en place, permettant la visualisation de la veine cave inférieure (VCI). </li><li> À ce stade, l&#39;isoflurane est réduite à un niveau d&#39;entretien de 2% et le taux d&#39;oxygène reste à 0,2 litres par minute pour le reste de la procédure chirurgicale. </li><li> Dissection est facilitée à l&#39;aide d&#39;un écouvillon applicateur stérile et extra délicats iris pince moitié tissus courbes. Des précautions doivent être prises dans la manipulation des tissus de souris car elles sont extrêmement fragiles. </li><li> Toutes les branches latérales IVC, des veines rénales à la bifurcation iliaque, sont ligués avec 7-0 points de suture Prolène non réactif. Retour branches resté brevet. </li><li> Dans le modèle d&#39;électrolyse IVC (EIM), un acier inoxydable 25G aiguille, attaché à un fil de cuivre recouvert d&#39;argent (KY-30-1-GRN, Electrospec, Dover, New Jersey) est insérée dans l&#39;exposé IVC caudale, (figure 1) et placés contre la paroi antérieure (anode). </li><li> Un autre fil est implanté sous la peau complétant le circuit (la cathode). </li><li> Un courant de 250 μAmps plus de 15 minutes a été appliquée en utilisant un stimulateur de l&#39;herbe S48 onde carrée et une unité de courant constant (Technologies herbe, un Astro-Med, Inc, West Warwick, RI). Les résultats directs actuels dans la formation de produits toxiques de l&#39;électrolyse qui érodent la surface endothéliale de la VCI promouvoir un environnement thrombogène et ultérieures formation de thrombus. </li><li> Après 15 minutes, l&#39;aiguille est retirée et un coton-tige est tenue délicatement en contact avec la zone pour prévenir les saignements </li><li> Chez les animaux de simulacre, l&#39;aiguille est placée dans la VCI et ensuite retiré, sans application du courant. </li><li> Le site est fermé laparotomie dans un mode bi-couche. Notre laboratoire utilise 5-0 Vicryl, une suture synthétique, dans un motif continu de fermer la paroi abdominale. Colle de peau adhésif est utilisé pour fermer la peau. Il n&#39;y a pas sutures externes pour l&#39;enlèvement. </li><li> Les souris sont ensuite récupérés dans une cage de souris individuelle, observé de près en post-opératoire (45 minutes à 2 heures) sous une lampe chauffante (distance minimale de 24 pouces loin de la cage), puis retournèrent à leurs unités de logement d&#39;origine. Médicaments contre la douleur et les agents anti-inflammatoires peuvent être utilisés si elle n&#39;interfère pas avec l&#39;objectif de l&#39;étude. Justification scientifique à retenir médicaments contre la douleur, vétérinaire, et l&#39;approbation ICUCA sont nécessaires. Notre laboratoire a montré que la buprénorphine ,0.05-0 0,1 mg / kg SQ est un excellent analgésique pré-et post-opératoire pour les souris. En outre, lidocaïne au 4mg/kg (0,4 ml / kg d&#39;une solution à 1%) peuvent être infusés dans le site d&#39;incision lors analgésiques systémiques peuvent brouiller les résultats expérimentaux. </li><li> En général, nous ne expérience post-opératoire des effets néfastes dus à la TVP. Toutefois, néfastes post-opératoire effets peuvent inclure la mort spontanée d&#39;anesthésie, les pertes sanguines chirurgicales, et une parésie partielle due à un traumatisme nerveux. Les animaux qui sont lents à récupérer peuvent être alimentés de ragondin gel ou humides ont chow placés sur le plancher de la cage afin de faciliter la récupération de l&#39;animal. Les animaux atteints de rompre les complications post-opératoires doivent être euthanasiés. </li><li> Au point le temps imparti, l&#39;euthanasie est réalisée avec humanité conformément aux recommandations énoncées par l&#39;American Veterinary Medical Association Directives sur l&#39;euthanasie pour les rongeurs. </li></ol> 3. Les résultats représentatifs L&#39;EIM est un modèle qui forme un thrombus dans la présence d&#39;un flux sanguin continu. Les chiffres suivants montrent les paramètres étudiés dans ce nouveau modèle. <img src="/files/ftp_upload/2737/2737fig1.jpg" alt="Figure 1" /> Figure 1 Zone definesthe anatomiques où un 25G en acier inoxydableaiguille, attaché à un fil de cuivre recouvert d&#39;argent (KY-30-1-GRN, Electrospec, Dover, New Jersey) est inséré. Notez que d&#39;un noeud lymphatique est pratiquement présent et contribue à un point de repère pour trouver la caudale IVC. <img src="/files/ftp_upload/2737/2737fig2.jpg" alt="Figure 2" /> Figure 2: poids du thrombus deux jours après l&#39;EIM dans les différentes souches. Comme prévu, le poids du thrombus était plus faible dans le PAI-1 souris KO et plus grand dans hypercoagulabilité souris delta CT (^ CT). <img src="/files/ftp_upload/2737/2737fig3.jpg" alt="Figure 3" /> Figure 3: la P-sélectine soluble, un fabricant de thrombose veineuse profonde, a été mesurée dans différentes souches. Les niveaux les plus bas ont été trouvés dans le PAI-1 souris KO alors que les niveaux les plus élevés ont été trouvés dans hypercoagulabilité souris CT delta. <img src="/files/ftp_upload/2737/2737fig4.jpg" alt="Figure 4" /> Figure 4 Corrélation entre le poids du thrombus et solubles de P-sélectine a été trouvé dans des souches différentes. Fait à noter, dans le groupe qui a généré le plus court de taille du thrombus, la P-sélectine soluble détectée était le plus bas (PAI-1 souris KO). Dans le groupe qui a généré la plus grande taille du thrombus, la P-sélectine soluble détectée était la plus élevée (hypercoagulabilité delta du CT). <img src="/files/ftp_upload/2737/2737fig5.jpg" alt="Figure 5" /> Figure 5: Afin de démontrer la présence de la circulation sanguine, une échographie a été réalisée chez des souris subissant MIE. La figure 5 montre l&#39;échographie réalisée dans une souris à 2 jours après l&#39;EIM. Puis l&#39;échantillon a été la récolte. Notez que la forme du thrombus suggèrent la formation de thrombus dans la présence d&#39;un flux

<ol>
	<li>Diaz, J. A., Hawley, A. E., Alvarado, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thrombogenesis+with+continuous+blood+flow+in+the+inferior+vena+cava.+A+novel+mouse+model.">Thrombogenesis with continuous blood flow in the inferior vena cava. A novel mouse model.</a> Thromb Haemost. 104, 366-375 (2010).</li><li>Eitzman, D. T., Westrick, R. J., Nabel, E. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasminogen+activator+inhibitor-1+and+vitronectin+promote+vascular+thrombosis+in+mice.">Plasminogen activator inhibitor-1 and vitronectin promote vascular thrombosis in mice.</a> Blood. 95, 577-580 (2000).</li><li>Myers, D., Farris, D., Hawley, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selectins+influence+thrombosis+in+a+mouse+model+of+experimental+deep+venous+thrombosis.">Selectins influence thrombosis in a mouse model of experimental deep venous thrombosis.</a> J Surg Res. 108, 212-221 (2002).</li><li>Myers, D. D., Hawley, A. E., Farris, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=P-selectin+and+leukocyte+microparticles+are+associated+with+venous+thrombogenesis.">P-selectin and leukocyte microparticles are associated with venous thrombogenesis.</a> J Vasc Surg. 38, 1075-1089 (2003).</li><li>Pierangeli, S. S., Barker, J. H., Stikovac, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+human+IgG+antiphospholipid+antibodies+on+an+in+vivo+thrombosis+model+in+mice.">Effect of human IgG antiphospholipid antibodies on an in vivo thrombosis model in mice.</a> Thromb Haemost. 71, 670-674 (1994).</li><li>Pierangeli, S. S., Liu, X. W., Barker, 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=Induction+of+thrombosis+in+a+mouse+model+by+IgG,+IgM+and+IgA+immunoglobulins+from+patients+with+the+antiphospholipid+syndrome.">Induction of thrombosis in a mouse model by IgG, IgM and IgA immunoglobulins from patients with the antiphospholipid syndrome.</a> Thromb Haemost. 74, 1361-1367 (1995).</li></ol>

La souris est un excellent outil de recherche pour les expériences in vivo. Ainsi, le développement de modèles de souris qui imitent de près les maladies ou états pathologiques sont nécessaires. Plusieurs modèles de thrombose veineuse souris ont été utilisés pour étudier TVP, y compris: photochimiques (2), la stase (3-4) et les traumatismes mécaniques (5-6). Cependant, aucun de ces modèles utilisent un stimulus interne endothéliales pour produire de thrombus dans la présence d&#39;un débit sanguin continu. L&#39;EIM, à l&#39;aide d&#39;électrolyse de relance au sein de l&#39;IVC, favorise thrombogénèse veineuse par l&#39;activation endothéliale, en présence de flux sanguin (1). Il est techniquement simple, facilement reproductible et a un taux de survie élevé (99%). Malgré le fait que le courant électrique est utilisé pour créer l&#39;électrolyse, la chaleur n&#39;est pas produite (1). Le modèle simule l&#39;EIM TVP cliniques, et sert donc comme un outil précieux pour étudier les mécanismes intrinsèques de la formation de thrombus et de la résolution. Le modèle EIM est également utile pour l&#39;avancement de nouvelles approches thérapeutiques contre la maladie d&#39;une thrombose.

<table border="1"><tbody><tr><th> Nom du réactif </th><th> Société </th><th> Numéro de catalogue </th><th> Commentaires (optionnel) </th></tr><tr><td> DMEM </td><td> Invitrogen </td><td> ABCD1234 </td><td></td></tr></tbody></table>

electrolytic inferior vena cava model (eim) of venous thrombosis

Les modèles animaux jouent un rôle essentiel dans la thrombose veineuse profonde (TVP) de recherche afin d&#39;étudier la formation de thrombus, la résolution du thrombus et de tester le potentiel des composés thérapeutiques (1). De nouveaux composés pour être utilisé dans le traitement et la prévention de la TVP sont en cours d&#39;élaboration. La livraison des composés antagonistes potentiels thérapeutiques pour une thrombose veineuse affectés a été problématique. Dans le contexte des applications thérapeutiques, un modèle qui utilise partielle stase et génère constamment thrombus dans une veine majeure a été récemment créé. La veine cave inférieure électrolytique modèle (EIM) est un modèle de souris de TVP qui permet la formation de thrombus dans la présence d&#39;un flux sanguin continu. Ce modèle permet d&#39;agents thérapeutiques à être en contact avec le thrombus de façon dynamique, et est plus sensible que d&#39;autres modèles de thrombose veineuse profonde (1). En outre, ce modèle de thrombose simule des situations cliniques de la formation de thrombus et est idéal pour étudier l&#39;activation des cellules endothéliales veineuses, la migration des leucocytes, thrombogénèse veineux, et de tester les applications thérapeutiques (1). Le modèle MIE est techniquement simple, facilement reproductible, crée cohérente tailles thrombus et permet un large échantillon (c.-à thrombus et paroi de la veine) qui est nécessaire aux fins d&#39;analyse.

Watch this Scientific Journal Video about Electrolytic Inferior Vena Cava Model EIM of Venous Thrombosis at JoVE.com

Electrolytic Inferior Vena Cava Model EIM of Venous Thrombosis

L&#39;induction d&#39;électrolyse de l&#39;activation endothéliale à la surface interne de la veine cave inférieure des résultats dans la formation de thrombus veineux de type due à l&#39;activation endothéliale et de sang partielle stase, deux composantes de la triade de Virchow.

Électrolytique veine cave inférieure Modèle (EIM) de la thrombose veineuse

Animal models serve a vital role in deep venous thrombosis (DVT) research in order to study thrombus formation, thrombus resolution and to test potential ...

electrolytic-inferior-vena-cava-model-eim-of-venous-thrombosis

Research

JoVE Journal

Medicine

Electrolytic Inferior Vena Cava Model (EIM) of Venous Thrombosis

Mouse Complete Stasis Model of Inferior Vena Cava Thrombosis

Venous thromboembolism (VTE) includes both deep vein thrombosis (DVT) and pulmonary embolism (PE). In the United States (U.S.), the high morbidity and mortality rates make VTE a serious health concern 1-2. After heart disease and stroke, VTE is the third most common vascular disease 3. In the U.S. alone, there is an estimated 900,000 people affected each year, with 300,000 deaths occurring annually 3. A reliable in vivo animal model to study the mechanisms of this disease is necessary.
The advantages of using the mouse complete stasis model of inferior vena cava thrombosis are several. The mouse model allows for the administration of very small volumes of limited availability test agents, reducing costs dramatically. Most promising is the potential for mice with gene knockouts that allow specific inflammatory and coagulation factor functions to be delineated. Current molecular assays allow for the quantitation of vein wall, thrombus, whole blood, and plasma for assays. However, a major concern involving this model is the operative size constraints and the friability of the vessels. Also, due to the small IVC sample weight (mean 0.005 grams) it is necessary to increase animal numbers for accurate statistical analysis for tissue, thrombus, and blood assays such as real-time polymerase chain reaction (RT-PCR), western blot, enzyme-linked immunosorbent (ELISA), zymography, vein wall and thrombus cellular analysis, and whole blood and plasma assays 4-8.
The major disadvantage with the stasis model is that the lack of blood flow inhibits the maximal effect of administered systemic therapeutic agents on the thrombus and vein wall.

The mouse complete stasis model of inferior vena cava thrombosis yields quantifiable amounts of vein wall tissue and thrombus. It has proven useful for evaluating interactions between the vein wall and the occlusive thrombus and in assessing the progression from acute to chronic inflammation.

Modèle de souris complète stase de la veine cave inférieure thrombose

Venous thromboembolism (VTE) includes both deep vein thrombosis (DVT) and pulmonary embolism (PE).  In the United States (U.S.), the high morbidity and ...

Recherche

Médecine

Implantation of Inferior Vena Cava Interposition Graft in Mouse Model

Biodegradable scaffolds seeded with bone marrow mononuclear cells (BMCs) are often used for reconstructive surgery to treat congenital cardiac anomalies. The long-term clinical results showed excellent patency rates, however, with significant incidence of stenosis. To investigate the cellular and molecular mechanisms of vascular neotissue formation and prevent stenosis development in tissue engineered vascular grafts (TEVGs), we developed a mouse model of the graft with approximately 1 mm internal diameter. First, the TEVGs were assembled from biodegradable tubular scaffolds fabricated from a polyglycolic acid nonwoven felt mesh coated with &#949;-caprolactone and L-lactide copolymer. The scaffolds were then placed in a lyophilizer, vacuumed for 24 hr, and stored in a desiccator until cell seeding. Second, bone marrow was collected from donor mice and mononuclear cells were isolated by density gradient centrifugation. Third, approximately one million cells were seeded on a scaffold and incubated O/N. Finally, the seeded scaffolds were then implanted as infrarenal vena cava interposition grafts in C57BL/6 mice. The implanted grafts demonstrated excellent patency (&#62;90%) without evidence of thromboembolic complications or aneurysmal formation. This murine model will aid us in understanding and quantifying the cellular and molecular mechanisms of neotissue formation in the TEVG.

To improve our knowledge of cellular and molecular neotissue formation, a murine model of the TEVG was recently developed. The grafts were implanted as infrarenal vena cava interposition grafts in C57BL/6 mice. This model achieves similar results to those achieved in our clinical investigation, but over a far shortened time-course.

Implantation de veine cave inférieure interposition de greffe en modèle de souris

Biodegradable scaffolds seeded with bone marrow mononuclear cells (BMCs) are often used for reconstructive surgery to treat congenital cardiac anomalies. ...

Ferric Chloride-induced Thrombosis Mouse Model on Carotid Artery and Mesentery Vessel

Severe thrombosis and its ischemic consequences such as myocardial infarction, pulmonary embolism and stroke are major worldwide health issues. The ferric chloride injury is now a well-established technique to rapidly and accurately induce the formation of thrombi in exposed veins or artery of small and large diameter. This model has played a key role in the study of the pathophysiology of thrombosis, in the discovery and validation of novel antithrombotic drugs and in the understanding of the mechanism of action of these new agents. Here, the implementation of this technique on a mesenteric vessel and carotid artery in mice is presented. The method describes how to label circulating leukocytes and platelets with a fluorescent dye and to observe, by intravital microscopy on the exposed mesentery, their accumulation at the injured vessel wall which leads to the formation of a thrombus. On the carotid artery, the occlusion caused by the clot formation is measured by monitoring the blood flow with a Doppler probe.

The FeCl3 induced thrombosis model in mice is described herein. A method to monitor thrombus growth by intravital microscopy observation on a mesenteric vessel and by blood flow measurement in the carotid artery is presented.

Chlorure ferrique induite souris thrombose type sur l&#39;artère carotide et Mesentery navire

Severe thrombosis and its ischemic consequences such as myocardial infarction, pulmonary embolism and stroke are major worldwide health issues. The ferric ...

Patch Angioplasty in the Rat Aorta or Inferior Vena Cava

Pericardial patches are commonly used in vascular surgery to close vessels. To facilitate studies of the neointimal hyperplasia that forms on the patch, we developed a rat model of patch angioplasty that can be used in either a vein or an artery, creating a patch venoplasty or a patch arterioplasty, respectively. Technical aspects of this model are discussed. The infra-renal IVC or aorta are dissected and then clamped proximally and distally. A 3 mm venotomy or arteriotomy is performed in the infrarenal inferior vena cava or aorta of 6 to 8 week-old Wistar rats. A bovine pericardial patch (3 mm x 1.5 mm x 0.6 mm) is then used to close the site using a 10-0 nylon suture. Compared to arterial patches, venous patches show increased neointimal thickness on postoperative day 7. This novel model of pericardial patch angioplasty can be used to examine neointimal hyperplasia on vascular biomaterials, as well as to compare the differences between the arterial and venous environments.

We have established a model of pericardial patch angioplasty that can be used in either small-diameter veins or arteries. This model can be used to compare venous and arterial neointimal hyperplasia formation.

Patch Angioplastie dans le Aorte Rat ou Veine cave inférieure

Pericardial patches are commonly used in vascular surgery to close vessels. To facilitate studies of the neointimal hyperplasia that forms on the patch, ...

A Rat Model of Orthotopic Liver Transplantation Using a Novel Magnetic Anastomosis Technique for Suprahepatic Vena Cava Reconstruction

The rat model of orthotopic liver transplantation (OLT) is essential for transplant research. It is a very sophisticated animal model and requires a steep learning curve. The introduction of the cuff technique for anastomosis of the portal vein (PV) and infrahepatic vena cava (IHVC) has significantly simplified the transplant procedure in rats. However, due to the short anterior wall of the recipients' suprahepatic vena cava (SHVC), the cuff technique is very difficult to use for the reconstruction of the SHVC. Most researchers in this field still use the hand-suture technique for SHVC reconstruction, which makes it the bottleneck step in rat orthotopic liver transplantation. The magnetic anastomosis technique (i.e., magnamosis) is a method of connecting two vessels using the attractive force between two magnets. Our recent study has shown that the magnetic anastomosis technique is superior to the hand-suture technique for SHVC reconstruction in rats. In this article, we show a step-by-step protocol for SHVC reconstruction in rats using the novel magnetic anastomosis technique. In this model, the reconstruction of the PV and IHVC was performed by the standard cuff technique, while the reconstruction of the bile duct (BD) was performed by a stent technique. The hepatic re-arterialization was not performed. The magnetic anastomosis technique made SHVC reconstruction much easier and significantly shortened the anphepatic phase. After a reasonable learning curve, even researchers without advanced microsurgical skills can produce reliable and reproducible results using this rat model of OLT.

The reconstruction of the suprahepatic vena cava (SHVC) remains a difficult step in rat orthotopic liver transplantation. In this article, we show a step-by-step protocol for SHVC reconstruction in rats using a novel magnetic anastomosis technique.

Un modèle de Rat de la Orthotopic Transplantation hépatique en utilisant une Technique nouvelle anastomose magnétique pour la Reconstruction de veine sus-hépatique

The rat model of orthotopic liver transplantation (OLT) is essential for transplant research. It is a very sophisticated animal model and requires a steep ...

Ferric Chloride-induced Canine Carotid Artery Thrombosis: A Large Animal Model of Vascular Injury

Occlusive arterial thrombosis leading to cerebral ischemic stroke and myocardial infarction contributes to ~13 million deaths every year globally. Here, we have translated a vascular injury model from a small animal into a large animal (canine), with slight modifications that can be used for pre-clinical screening of prophylactic and thrombolytic agents. In addition to the surgical methods, the modified protocol describes the step-by-step methods to assess carotid artery canalization by angiography, detailed instructions to process both the brain and carotid artery for histological analysis to verify carotid canalization and cerebral hemorrhage, and specific parameters to complete an assessment of downstream thromboembolic events by utilizing magnetic resonance imaging (MRI). In addition, specific procedural changes from the previously well-established small animal model necessary to translate into a large animal (canine) vascular injury are discussed.

Here, we present the modifications necessary to a well characterized and commonly used small animal ferric chloride-induced (FeCl3) carotid artery injury model for use in a large animal vascular injury model. The resulting model can be utilized for pre-clinical trial assessment of both prophylactic and thrombolytic pharmacological and mechanical interventions.

Thrombose de l’artère carotide Canine induite par le chlorure ferrique : Un grand modèle Animal de lésion vasculaire

Occlusive arterial thrombosis leading to cerebral ischemic stroke and myocardial infarction contributes to ~13 million deaths every year globally. Here, ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

Mesure de la contractilité isométrique de l’artère mésentérique de souris à l’aide de fil myographie

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...

Murine Model of Central Venous Stenosis using Aortocaval Fistula with an Outflow Stenosis

Central venous stenosis is an important entity contributing to arteriovenous fistula (AVF) failure. A murine AVF model was modified to create a partial ligation of the inferior vena cava (IVC) in the outflow of the fistula, mimicking central venous stenosis. Technical aspects of this model are introduced. The aorta and IVC are exposed, following an abdominal incision. The infra-renal aorta and IVC are dissected for proximal clamping, and the distal aorta is exposed for puncture. The IVC at the midpoint between the left renal vein and the aortic bifurcation is carefully dissected to place an 8-0 suture beneath the IVC. After clamping the aorta and IVC, an AVF is created by puncturing the infra-renal aorta through both walls into the IVC with a 25 G needle, followed by ligating a 22 G intra-venous (IV) catheter and IVC together. The catheter is then removed, creating a reproducible venous stenosis without occlusion. The aorta and IVC are unclamped after confirming primary hemostasis. This novel model of central vein stenosis is easy to perform, reproducible, and will facilitate studies on AVF failure.

An aortocaval fistula was created by puncturing the murine infra-renal aorta through both walls into the inferior vena cava and was followed by creation of a stenosis in its outflow via partial ligation of the inferior vena cava. This reproducible model can be used to study central venous stenosis.

Modèle murine de la sténose veineuse centrale utilisant la fistule d'Aortocaval avec une stenose sortante

Central venous stenosis is an important entity contributing to arteriovenous fistula (AVF) failure. A murine AVF model was modified to create a partial ...

Image Acquisition Method for the Sonographic Assessment of the Inferior Vena Cava

Over the past several decades, clinicians have incorporated several applications of diagnostic point-of-care ultrasound (POCUS) into medical decision-making. Among the applications of POCUS, imaging the inferior vena cava (IVC) is practiced by a wide variety of specialties, such as nephrology, emergency medicine, internal medicine, critical care, anesthesiology, pulmonology, and cardiology. Although each specialty uses IVC data in slightly different ways, most medical specialties, at minimum, attempt to use IVC data to make predictions about intravascular volume status. While the relationship between IVC sonographic data and intravascular volume status is complex and highly context-dependent, all clinicians should collect the sonographic data in standardized ways to ensure repeatability. This paper describes standardized IVC image acquisition including patient positioning, transducer selection, probe placement, image optimization, and the pitfalls and limitations of IVC sonographic imaging.&#160;This paper also describes the commonly performed anterior IVC long-axis view and three other views of the IVC that can each provide helpful diagnostic information when the anterior long-axis view is difficult to obtain or interpret.

Point-of-care ultrasound evaluation of the inferior vena cava (IVC) is commonly utilized to identify, among other things, the volume status. Imaging should be performed systematically to ensure repeatability. This manuscript reviews the methods and pitfalls of sonographic IVC examination.

Méthode d’acquisition d’images pour l’évaluation échographique de la veine cave inférieure

Over the past several decades, clinicians have incorporated several applications of diagnostic point-of-care ultrasound (POCUS) into medical ...

Point-Of-Care Ultrasound Screening for Proximal Lower Extremity Deep Venous Thrombosis

Acute lower extremity deep venous thrombosis (DVT) is a serious vascular disorder that requires accurate and early diagnosis to prevent life-threatening sequelae. While whole leg compression ultrasound with color and spectral Doppler is commonly performed in radiology and vascular labs, point-of-care ultrasound (POCUS) is becoming more common in the acute care setting. Providers appropriately trained in focused POCUS can perform a rapid bedside examination with high sensitivity and specificity in critically ill patients. This paper describes a simplified yet validated approach to POCUS by describing a three-zone protocol for lower extremity DVT POCUS image acquisition. The protocol explains the steps in obtaining vascular images at six compression points in the lower extremity. Beginning at the level of the proximal thigh and moving distally to the popliteal space, the protocol guides the user through each of the compression points in a stepwise manner: from the common femoral vein to the femoral and deep femoral vein bifurcation, and, finally, to the popliteal vein. Further, a visual aid is provided that may assist providers during real-time image acquisition. The goal in presenting this protocol is to help make proximal lower extremity DVT exams more accessible and efficient for POCUS users at the patient&#39;s bedside.

Traditionally, lower extremity deep venous thrombosis (DVT) is diagnosed by radiology-performed venous duplex ultrasound. Providers appropriately trained in focused point-of-care ultrasound (POCUS) can perform a rapid bedside examination with high sensitivity and specificity in critically ill patients. We describe the scanning technique for focused POCUS DVT lower extremity examination.

Dépistage échographique au point de service de la thrombose veineuse profonde proximale des membres inférieurs

Acute lower extremity deep venous thrombosis (DVT) is a serious vascular disorder that requires accurate and early diagnosis to prevent life-threatening ...