Este trabalho foi financiado em parte pelos Institutos Nacionais de Saúde Grants R56-HL095498, R01-HL-095498 (para AD), R01-HL128406, o mérito revisão Award I01-BX002336 do Departamento de Assuntos de Veteranos Biomedical Research Laboratory Estados Unidos e Programa de desenvolvimento (a AD), um Departamento de Yale de Cirurgia prêmio Ohse (a AD), um Sarnoff Cardiovascular Foundation Fellowship (a JMS), e através dos recursos ea utilização de instalações no Connecticut Healthcare System Veterans Affairs (West Haven, CT ). retalhos de pericárdio bovino foram generosamente fornecidos pela LeMaitre Vascular Inc. (Burlington, MA).

deve ser obtida a aprovação pela Comissão de adequada Institucional animal cuidado e uso, indicando que o seu protocolo segue as orientações do comitê de ética de pesquisa animal da sua instituição. 1. A anestesia e procedimentos pré-operatórios <ol><li> Anestesiar ratos Wistar macho, pesando cerca de 200 g, com isoflurano vaporizado 3% e 1 L / min de oxigénio administrado em uma câmara de indução acrílico. </li><li> Confirmar anestesia adequada através de uma falta de reação a um dedo do pé e cauda pitada. Coloque pomada sobre os olhos para evitar a secura, enquanto os animais estão sob anestesia. Posicione o supino cada rato na placa de operação de plástico e colocar uma máscara de silicone para entregar vaporizado 2-3% de isoflurano por inalação contínua. Não deixe um animal sem supervisão até que tenha recuperado a consciência suficiente para manter decúbito esternal. </li><li> Enquanto o uso de luvas estéreis, remover os pêlos do abdômen ventral usando um removedor de pêlos. Buprenorphine, por via subcutânea ou por via intraperitoneal, é frequentemente dada neste ponto. </li></ol> 2. Procedimentos Operativos <ol><li> venoplastia remendo <ol><li> Antes da cirurgia, cortar a placa de pericárdio bovino utilizando uma microtesoura a um tamanho de 3 mm x 1,5 mm x 0,6 mm. Embeber o penso em 10 ml de soro fisiológico esterilizado durante 5 minutos numa placa de cultura de células. </li><li> Prepare o local da incisão com um anti-séptico tópico de acordo com seu protocolo institucional e aplicar um campo cirúrgico. Use luvas e instrumentos esterilizados para manter uma técnica asséptica durante toda a cirurgia. A anestesia local pode ser injectado no local da incisão na pele planeado. </li><li> Utilizando um bisturi, fazer uma incisão abdominal na linha média que se estende desde o nível da xifóide até imediatamente acima do púbis. </li><li> Insira um afastador e eviscerar todas as entranhas da cavidade abdominal para o lado direito. Enrole as entranhas em gaze embebida em soro fisiológico. </li><li> Expor o iveia cava nfrarenal (IVC). O local da implantação remendo é de aproximadamente 2 mm abaixo do nível da origem das veias renais; dissecar o IVC gratuito neste site. Ligadura e dividir todas as veias lombares e tributárias a este nível com 6-0 nylon. </li><li> Coloque dois grampos de microcirurgia em ambos proximal e distal infarenal IVC. Executar uma venotomia com uma agulha G 25 por punção da parede anterior do IVC, em seguida, estendê-lo para cerca de 3 mm, utilizando uma tesoura (Figura 1A). </li><li> Feche a venotomia com o patch usando correr ou interrompidos 10-0 suturas de nylon (Figura 1B). </li><li> Completar o fechamento venoplastia. Retire o grampo distal primeiro a ventilar o patch e em seguida, remover o grampo proximal para restaurar o fluxo de sangue para o IVC. </li><li> Confirmar hemostasia através da observação durante 30 s sem compressão. Retornar as entranhas à sua posição natural. Fechar o abdómen com uma sutura contínua de acordo com protocolos aprovados animais. </li></ol></li><li> arterioplastia remendo <ol><li> Antes da cirurgia, cortar a placa de pericárdio bovino utilizando uma microtesoura a um tamanho de 3 mm x 1,5 mm x 0,6 mm. Sature em soro fisiológico esterilizado. </li><li> Prepare o local da incisão com um anti-séptico tópico e aplicar um campo cirúrgico. Use luvas e instrumentos esterilizados para manter uma técnica asséptica durante toda a cirurgia. </li><li> Utilizando um bisturi, fazer uma incisão abdominal na linha média que se estende desde o nível da xifóide até imediatamente acima do púbis. </li><li> Insira um afastador e eviscerar todas as entranhas da cavidade abdominal para o lado direito. Enrole as entranhas em gaze embebida em soro fisiológico. </li><li> Expor a aorta. O local da implantação remendo é de aproximadamente 2 mm abaixo do nível da origem das artérias renais; dissecar a aorta gratuito neste site. Ligadura e dividir todas as artérias lombares, a este nível com 6-0 nylon. </li><li> Grampo da aorta infra-renal. Use uma agulha G 25 para executar uma arteriotomia por puncturing a parede anterior da aorta e, em seguida, estendê-lo para cerca de 3 tesoura mm usando (Figura 1C). </li><li> Fechar a arteriotomia com o remendo utilizando suturas de nylon 10-0 execução (Figura 1D). Completar o fechamento arterioplastia. Retire o grampo distal primeiro a ventilar o patch e em seguida, remover o grampo proximal para restaurar o fluxo de sangue para a aorta. </li><li> Confirmar hemostasia através da observação durante 30 s sem compressão. Retornar as entranhas à sua posição natural. Fechar o abdómen com uma sutura contínua de acordo com protocolos aprovados animais. </li></ol></li></ol> Procedimentos 3. pós-operatórias <ol><li> Após o encerramento do abdômen, interromper a anestesia. Aplicar cuidados pós-operatórios, incluindo analgesia e cuidados de feridas, de acordo com as instruções recomendadas pelo Comitê de Cuidado e Uso Institucional Animal. </li><li> Para analgesia, usar buprenorfina a 0,1 mg / kg por via intramuscular não menos do que a cada 12 h durante 24 h sigaing os procedimentos cirúrgicos. Verifique o estado do animal todos os dias na sala de animal, assegurando a recuperação adequada do período peri-operatório, bem como o tratamento adequado da dor pós-cirúrgica. Não devolva um animal que foi submetido a uma cirurgia para a companhia de outros animais até que ele se recuperou totalmente. </li></ol><style type="text/css">p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px Helvetica}
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<ol>
	<li>Muto, A., Nishibe, T., Dardik, H., Dardik, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patches+for+carotid+artery+endarterectomy:+current+materials+and+prospects.">Patches for carotid artery endarterectomy: current materials and prospects.</a> J Vasc Surg. 50 (1), 206-213 (2009).</li><li>Li, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+usage+and+future+directions+for+the+bovine+pericardial+patch.">Current usage and future directions for the bovine pericardial patch.</a> Ann Vasc Surg. 25 (4), 561-568 (2011).</li><li>Biasi, G. M., Sternjakob, S., Mingazzini, P. M., Ferrari, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nine-year+experience+of+bovine+pericardium+patch+angioplasty+during+carotid+endarterectomy.">Nine-year experience of bovine pericardium patch angioplasty during carotid endarterectomy.</a> J Vasc Surg. 36 (2), 271-277 (2002).</li><li>Papakostas, J. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+the+vascu-guard+bovine+pericardium+patch+for+arteriotomy+closure+in+carotid+endarterectomy.+Early+and+long-term+results.">Use of the vascu-guard bovine pericardium patch for arteriotomy closure in carotid endarterectomy. Early and long-term results.</a> Ann Vasc Surg. 28 (5), 1213-1218 (2014).</li><li>Ohwada, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glutaraldehyde-fixed+heterologous+pericardium+for+vena+cava+grafting+following+hepatectomy.">Glutaraldehyde-fixed heterologous pericardium for vena cava grafting following hepatectomy.</a> Hepatogastroenterology. 46 (26), 855-858 (1999).</li><li>Mori, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Standard+hepatic+vein+reconstruction+with+patch+plasty+using+the+native+portal+vein+in+adult+living+donor+liver+transplantation.">Standard hepatic vein reconstruction with patch plasty using the native portal vein in adult living donor liver transplantation.</a> Liver Transpl. 18 (5), 602-607 (2012).</li><li>Bai, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pericardial+patch+venoplasty+heals+via+attraction+of+venous+progenitor+cells.">Pericardial patch venoplasty heals via attraction of venous progenitor cells.</a> Physiological Reports. 4 (12), (2016).</li><li>Li, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pericardial+patch+angioplasty+heals+via+an+Ephrin-B2+and+CD34+positive+cell+mediated+mechanism.">Pericardial patch angioplasty heals via an Ephrin-B2 and CD34 positive cell mediated mechanism.</a> PLoS One. 7 (6), 38844 (2012).</li><li>Bai, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pretreatment+of+pericardial+patches+with+antibiotics+does+not+alter+patch+healing+in+vivo.">Pretreatment of pericardial patches with antibiotics does not alter patch healing in vivo.</a> J Vasc Surg. 63 (4), 1063-1073 (2016).</li><li>Muto, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Eph-B4+prevents+venous+adaptive+remodeling+in+the+adult+arterial+environment.">Eph-B4 prevents venous adaptive remodeling in the adult arterial environment.</a> J Exp Med. 208 (3), 561-575 (2011).</li></ol>

The authors have nothing to disclose.

Descreve-se um modelo de angioplastia no rato que pode ser utilizado tanto em veias ou artérias, criando um remendo ou venoplastia arterioplastia remendo, respectivamente. Usando este modelo de pericárdio, que mostrou hiperplasia neointimal agressivo e estável no rato VCI venoplastia em comparação com o arterioplastia da aorta (Figura 2) 7, 8. Vários aspectos técnicos são notáveis. No arterioplastia da aorta, é importante que as suturas são apertadas e adequado em número e / ou espaçamento para evitar a fuga de sangue no aumento da pressão arterial do meio. No venoplastia IVC, é importante executar todas as manobras operativas, com especial cuidado e delicadeza, como a parede IVC é extremamente fina e frágil. Além disso, lombar e pequeno afluente veias em torno do local do implante deve ser cuidadosamente dissecados e ligados a prevenir o sangramento. Em ambos arterial e procedimentos venosas, o grampo distal é removido primeiro a ventilar o ar luminal e para evitar uma embolia pulmonar. A braçadeira proximal é então removido para restaurar o fluxo sanguíneo distai. Por último, quando a perfuração da aorta ou da parede da VCI, não perfurar a parede posterior; Se a parede posterior é perfurada, uma sutura 10-0 deve ser usada para fechar o orifício. Uma desvantagem da angioplastia remendo na aorta é o desenvolvimento de pseudo-aneurismas em momentos posteriores (por exemplo, pós-operatório dia 30). No entanto, foram raramente observados quaisquer pseudoaneurismas nos dias pós-operatórios 7 e 14, o que sugere a utilidade deste modelo durante as primeiras 2 semanas após o procedimento para estudar a formação da neoíntima em ambos os venosa ou arterial o ambiente 7, 9. Pequenos animais patch de angioplastia tem várias vantagens em relação aos modelos interposição de enxerto. Em primeiro lugar, a corça navio de acolhimentos não precisa ser seccionado, já que apenas uma incisão da parede anterior é feita; Isto reduz o tempo cirúrgico e minimiza o risco de hemorragia. Em segundo lugar, o enxerto de interposição requer duas anastomoses, aumentando o tempo operatório e risco de complicações, bem como estendendo-se a curva de aprendizagem. Remendo angioplastia requer apenas uma única anastomose, reduzindo o tempo de operação e o risco de complicações. Em terceiro lugar, remendo angioplastia intrinsecamente reduz o risco de estenose no local da anastomose, potencialmente permitindo um aumento do tempo de observação pós-operatória 10. Em conclusão, nós descrevemos um método para realizar angioplastia que utiliza placas de pericárdio para fechar os vasos de pequeno diâmetro; o procedimento é igualmente aplicável a ambas as veias e artérias. Pericárdio venoplastia remendo mostra a formação neointimal mais agressivo em relação ao modelo arterioplastia às vezes pós-operatório imediato. Este resultado sugere a utilidade deste modelo iN determinar as diferenças nas interacções entre a venosa e os ambientes arteriais com biomateriais implantáveis. Além disso, diferentes tipos de composições de remendo podem ser examinados para testar a resposta a esses materiais diferentes.

Cirurgiões vasculares comumente vasos sanguíneos estreitos com retalhos de pericárdio, seja bovina ou suína, para reduzir o risco de reestenose 1, 2. Em cirurgia arterial, pericárdico angioplastia reduz a taxa de restenose em comparação com um primário de fecho 3, 4. Venoplastia patch também é realizada de forma semelhante para fechar veias, embora com menor frequência quando comparados aos procedimentos arteriais 5, 6. Patches geralmente desenvolvem hiperplasia neointimal em suas superfícies luminais; No entanto, o mecanismo de formação da neointima permanece pouco clara, especialmente em comparação das diferenças na formação neointimal entre o arteriais e venosas ambientes. Nós já mostraram que pericárdio atrair células progenitoras, tanto no arterial e os ambientes venosas e que angioplastia venosa mostra mais umaa formação da neointima ggressive, em comparação com as amostras arteriais 7, 8. Neste estudo, descrevemos o modelo de rato de angioplastia pericárdio que é comum para fechar ambas as veias e artérias e que podem ser usadas para estudar a formação da neointima; este método é um modelo de pequenos animais de uma técnica cirúrgica utilizada em pacientes humanos. O modelo do rato tem um diâmetro maior do que o modelo de ratinho, facilitando aspectos técnicos da cirurgia e melhorar a curva de aprendizagem para o modelo.

<table border="0" cellpadding="0" cellspacing="0" width="523">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Bovine pericardial patch</td>
			<td colspan="2" style="width:307px;">LeMaitre Vascular</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Vascular clamp</td>
			<td>Roboz Surgical Instrument Co.</td>
			<td>RS-5424</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Clamp applying forceps</td>
			<td>Roboz Surgical Instrument Co</td>
			<td>RS-5410</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">10-0 Prolene suture</td>
			<td>Arosurgical Co.</td>
			<td>T05A10N10-13</td>
		</tr>
	</tbody>
</table>

patch angioplasty in the rat aorta or inferior vena cava

retalhos de pericárdio são comumente usados ​​em cirurgia vascular para fechar vasos. Para facilitar os estudos da hiperplasia neointimal que se forma sobre o patch, foi desenvolvido um modelo de rato de angioplastia que pode ser usado em qualquer uma veia ou uma artéria, criando um venoplastia patch ou um arterioplastia remendo, respectivamente. são discutidos aspectos técnicos deste modelo. O VCI e aorta infra-renal são dissecados e depois preso proximal e distal. Um venotomia 3 mm ou arteriotomia é realizada na veia cava inferior infra-renal da aorta ou de 6 a ratos Wistar 8 semanas de idade. A placa de pericárdio bovino (3 mm x 1,5 mm x 0,6 mm) é então usado para fechar o site usando uma sutura 10-0 nylon. Em comparação com manchas arteriais, venosas manchas mostram aumento da espessura da neointima no dia pós-operatório 7. Este novo modelo de angioplastia pericárdio pode ser usado para examinar a hiperplasia neointimal em biomateriais vasculares, bem como para comparar as diferenças entre a arterial e venosaambientes.

Após a angioplastia, não houve trombose venosa, quer em (n = 42) ou arterial grupos patch (n = 24). Sobrevivência no dia 7 foi de 100% em ambos os grupos, quer com um venosa ou patch arterial. As manchas foram colhidas no dia 7 e coradas com hematoxilina e eosina, e a espessura da neointima foi comparado como descrito anteriormente 7. Por causa da diferença morfológica distinta entre o adesivo e a neoíntima, é muito fácil para discriminar a neoíntima. No penso venosa, houve uma camada distinta da neoíntima espessa no lado luminal do emplastro, com mais células acumuladas no neoíntima (Figura 2A, 2C); no remendo arterial, houve uma camada de neo-íntima muito mais fino, com apenas algumas células ligadas para o lado luminal do remendo (Figura 2B, 2D). Os wa neoï¿½tima<html> é significativamente mais espessa no patch venosa em comparação com o patch da artéria (Figura 2E). Resultados semelhantes foram obtidos no dia 14 (dados não mostrados). Estes resultados mostram que o modelo remendo venoplastia é superior em relação a outros modelos para adquirir uma espessura da neointima num curto período de tempo. <img alt="figura 1" src="/files/ftp_upload/55253/55253fig1.jpg" /> Figura 1: Rat Pericárdica patch Angioplastia. (A) fotografia Representante mostrando a venotomia IVC. (B) fotografia Representante mostrando o IVC após a colocação do patch. (C) fotografia Representante mostrando a arteriotomia aórtica. (D) fotografia representativa que mostra a aorta após a colocação do patch. Um, aorta; IVC, veia cava inferior; P, pericárdio; *, Íntima posterior da VCI e aorta; marcações de régua são 1 mm.3fig1large.jpg &quot;target =&quot; _ blank &quot;&gt; Clique aqui para ver uma versão maior desta figura. <img alt="Figura 2" src="/files/ftp_upload/55253/55253fig2.jpg" /> Figura 2: Agressivo hiperplasia neointimal na correcção de venoplastia comparação com remendo Arterioplastia no dia 7. (A) Representante fotografia de baixo consumo que mostra a venoplastia patch no dia 7, que foi corada com H &amp; E. (B) Representante fotografia de baixo consumo que mostra a angioplastia no dia 7, que foi corado com H &amp; E. (C) Representante fotografia de alta potência que mostra a formação neointimal na venoplastia patch. (D) Representante fotografia de alta potência que mostra a formação neointimal na arterioplastia patch. Barra de escala = 0,5 mm; alta potência = 100 mm. P, remendo; L, VCI e aorta lúmen; N, neoíntima. Showi gráfico (E) Barng aumento da espessura da neointima no venoplastia comparação com arterioplastia. A barra de erro denota o SEM; * P = 0,0015, teste t; n = 4. <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55253/55253fig2large.jpg" target="_blank">Por favor clique aqui para ver uma versão maior desta figura.</a>

Watch this Scientific Journal Video about Patch Angioplasty in the Rat Aorta or Inferior Vena Cava at JoVE.com

Patch Angioplasty in the Rat Aorta or Inferior Vena Cava

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.

Remendar Angioplastia na Rat aorta ou veia cava inferior

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

patch-angioplasty-in-the-rat-aorta-or-inferior-vena-cava

Nanyang Technological University

Research

JoVE Journal

Medicine

10.5K visualizações.  Yale University. 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.

Vídeo: Patch Angioplasty in the Rat Aorta or Inferior Vena Cava

Hyperinsulinemic-Euglycemic Clamp in the Conscious Rat

Type 2 diabetes (T2D) is rapidly rising in prevalence. Characterized by either inadequate insulin production or the inability to utilize insulin produced, T2D results in elevated blood glucose levels. The "gold-standard" in assessing insulin sensitivity is a hyperinsulinemic-euglycemic clamp or insulin clamp. In this procedure, insulin is infused at a constant rate resulting in a drop in blood glucose. To maintain blood glucose at a constant level, exogenous glucose (D50) is infused into the venous circulation. The amount of glucose infused to maintain homeostasis is indicative of insulin sensitivity. Here, we show the basic clamp procedure in the chronically catheterized, unrestrained, conscious rat. This model allows blood to be collected with minimal stress to the animal. Following the induction of anesthesia, a midline incision is made and the left common carotid artery and right jugular vein are catheterized. Inserted catheters are flushed with heparinized saline, then exteriorized and secured. Animals are allowed to recover for 4-5 days prior to experiments, with weight gain monitored daily. Only those animals who regain weight to pre-surgery levels are used for experiments. On the day of the experiment, rats are fasted and connected to pumps containing insulin and D50. Baseline glucose is assessed from the arterial line and used a benchmark throughout the experiment (euglycemia). Following this, insulin is infused at a constant rate into the venous circulation. To match the drop in blood glucose, D50 is infused. If the rate of D50 infusion is greater than the rate of uptake, a rise in glucose will occur. Similarly, if the rate is insufficient to match whole body glucose uptake, a drop will occur. Titration of glucose continues until stable glucose readings are achieved. Glucose levels and glucose infusion rates during this stable period are recorded and reported. Results provide an index of whole body insulin sensitivity. The technique can be refined to meet specific experimental requirements. It is further enhanced by the use of radioactive tracers that can determine tissue specific insulin-stimulated glucose uptake as well as whole body glucose turnover.

The hyperinsulinemic-euglycemic clamp is the "gold standard" for the assessment of insulin action. Insulin is infused at a constant rate stimulating glucose uptake. The amount of exogenous glucose infused to counter this drop is indicative of insulin sensitivity. Here the procedure is performed on a conscious, unrestrained rat.

Hiperinsulinêmico euglicêmico-Clamp in the Rat Consciente

Type 2 diabetes (T2D) is rapidly rising in prevalence. Characterized by either inadequate insulin production or the inability to utilize insulin produced, ...

Medicina

Electrolytic Inferior Vena Cava Model (EIM) of Venous Thrombosis

Animal models serve a vital role in deep venous thrombosis (DVT) research in order to study thrombus formation, thrombus resolution and to test potential therapeutic compounds (1). New compounds to be utilized in the treatment and prevention of DVT are currently being developed. The delivery of potential therapeutic antagonist compounds to an affected thrombosed vein has been problematic. In the context of therapeutic applications, a model that uses partial stasis and consistently generates thrombi within a major vein has been recently established. The Electrolytic Inferior vena cava Model (EIM) is mouse model of DVT that permits thrombus formation in the presence of continuous blood flow. This model allows therapeutic agents to be in contact with the thrombus in a dynamic fashion, and is more sensitive than other models of DVT (1). In addition, this thrombosis model closely simulates clinical situations of thrombus formation and is ideal to study venous endothelial cell activation, leukocyte migration, venous thrombogenesis, and to test therapeutic applications (1). The EIM model is technically simple, easily reproducible, creates consistent thrombi sizes and allows for a large sample (i.e. thrombus and vein wall) which is required for analytical purposes.

Electrolytic Inferior Vena Cava Model EIM of Venous Thrombosis

The electrolytic induction of endothelial activation to the internal surface of the Inferior Vena Cava results in venous type thrombus formation due to endothelial activation and partial blood stasis, two components of Virchow's triad.

Eletrolítico Veia Cava Inferior Model (EIM) de trombose venosa

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

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.

Modelo do mouse completa de Stasis Inferior Trombose da veia cava

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

Angiogenesis in the Ischemic Rat Lung

The adult lung is perfused by both the systemic bronchial artery and the entire venous return flowing through the pulmonary arteries. In most lung pathologies, it is the smaller systemic vasculature that responds to a need for enhanced lung perfusion and shows robust neovascularization. Pulmonary vascular ischemia induced by pulmonary artery obstruction has been shown to result in rapid systemic arterial angiogenesis in man as well as in several animal models. Although the histologic assessment of the time course of bronchial artery proliferation in rats was carefully described by Weibel 1, mechanisms responsible for this organized growth of new vessels are not clear. We provide surgical details of inducing left pulmonary artery ischemia in the rat that leads to bronchial neovascularization. Quantification of the extent of angiogenesis presents an additional challenge due to the presence of the two vascular beds within the lung. Methods to determine functional angiogenesis based on labeled microsphere injections are provided.

The lung is perfused by both the systemic bronchial artery and pulmonary arteries. In most lung pathologies, it is the smaller systemic vasculature that shows robust neovascularization. Cessation of pulmonary blood flow promotes brisk bronchial angiogenesis. We provide surgical details of inducing left pulmonary artery ischemia that promotes bronchial neovascularization.

Angiogênese no pulmão de rato Isquêmica

The  adult lung is perfused by both the systemic bronchial artery and the entire  venous return flowing through the pulmonary arteries. In most lung ...

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.

Implantação de Veia Cava Inferior interposição de enxerto no Rato Modelo

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

Scleral Cross-linking Using Riboflavin and Ultraviolet-A Radiation for Prevention of Axial Myopia in a Rabbit Model

Myopic individuals, especially those with severe myopia, are at higher-than-normal risk of cataract, glaucoma, retinal detachment and chorioretinal abnormalities. In addition, pathological myopia is a common irreversible cause of visual impairment and blindness1-3. Our study demonstrates the effect of scleral crosslinking using riboflavin and ultraviolet-A radiation on the development of axial myopia in a rabbit model. The axial length of the eyeball was measured by A-scan ultrasound in New Zealand white rabbits aged 13 days (male and female). The eye then underwent 360&#176; conjunctival peritomy with scleral crosslinking, followed by tarsorrhaphy. Axial elongation was induced in 13 day-old New Zealand rabbits by suturing their right eye eyelids (tarsorrhaphy). The eyes were divided into quadrants, and every quadrant had two scleral irradiation zones, each with an area of 0.2 cm&#178; and a radius of 4 mm. Crosslinking was performed by dropping 0.1% dextran-free riboflavin-5-phosphate onto the irradiation zones 20 sec before ultraviolet-A irradiation and every 20 sec during the 200 sec irradiation time. UVA radiation (370 nm) was applied perpendicular to the sclera at 57 mW/cm&#178; (total UVA light dose, 57 J/cm&#178;). Tarsorrhaphies were removed on day 55, followed by repeated axial length measurements. This study demonstrates that scleral crosslinking with riboflavin and ultraviolet-A radiation effectively prevents occlusion-induced axial elongation in a rabbit model.

We demonstrate the effect of scleral crosslinking with riboflavin and UVA on an axial elongation rabbit eye. Axial elongation was induced in 13 day-old New Zealand rabbits (male and female) by suturing their right eye eyelids (tarsorrhaphy).

Escleral reticulação Usando ultravioleta e riboflavina-A radiação de Prevenção de Axial Miopia em um modelo de coelho

Myopic individuals, especially those with severe myopia, are at higher-than-normal risk of cataract, glaucoma, retinal detachment and chorioretinal ...

A Model of Cardiac Remodeling Through Constriction of the Abdominal Aorta in Rats

Heart failure is one of the leading causes of death worldwide. It is a complex clinical syndromethat includes fatigue, dyspnea, exercise intolerance, and fluid retention. Changes in myocardial structure, electrical conduction, and energy metabolism develop with heart failure, leading to contractile dysfunction, increased risk of arrhythmias, and sudden death. Hypertensive heart disease is one of the key contributing factors of cardiac remodeling associated with heart failure. The most commonly-used animal model mimicking hypertensive heart disease is created via surgical interventions, such as by narrowing the aorta. Abdominal aortic constriction is a useful experimental technique to induce a pressure overload, which leads to heart failure. The surgery can be easily performed, without the need for chest opening or mechanical ventilation. Abdominal aortic constriction-induced cardiac pathology progresses gradually, making this model relevant to clinical hypertensive heart failure. Cardiac injury and remodeling can be observed 10 weeks after the surgery. The method described here provides a simple and effective approach to produce a hypertensive heart disease animal model that is suitable for studying disease mechanisms and for testing novel therapeutics.

A rat model of abdominal aortic constriction that induces cardiac hypertrophy and remodeling is described. An efficient, highly-reproducible, and minimally-invasive method is used to provide a simple yet useful platform for research in myocardial hypertrophy and dysfunction.

Um Modelo de Cardiologia remodela Através constrição da Aorta Abdominal em Ratos

Heart failure is one of the leading causes of death worldwide. It is a complex clinical syndromethat includes fatigue, dyspnea, exercise intolerance, and ...

Balloon-based Injury to Induce Myointimal Hyperplasia in the Mouse Abdominal Aorta

The use of animal models is essential for a better understanding of MH, one major cause for arterial stenosis.In this article, we demonstrate a murine balloon denudation model, which is comparable with established vessel injury models in large animals. The aorta denudation model with balloon catheters mimics the clinical setting and leads to comparable pathobiological and physiological changes. Briefly, after performing a horizontal incision in the aorta abdominalis, a balloon catheter will be inserted into the vessel, inflated, and introduced retrogradely. Inflation of the balloon will lead to intima injury and overdistension of the vessel. After removing the catheter, the aortic incision will be closed with single stiches. The model shown in this article is reproducible, easy to perform, and can be established quickly and reliably. It is especially suitable for evaluating expensive experimental therapeutic agents, which can be applied in an economical fashion. By using different knockout-mouse strains, the impact of different genes on MH development can be assessed.

This article demonstrates a murine model to study the development of myointimal hyperplasia (MH) after aortic balloon injury.

Lesão baseada no balão para induzir a hiperplasia Myointimal da Aorta Abdominal de Mouse

The use of animal models is essential for a better understanding of MH, one major cause for arterial stenosis.In this article, we demonstrate a murine ...

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.

Um modelo do rato de ortotópico transplante hepático, usando uma técnica de anastomose magnético romance para reconstrução de veia Cava Suprahepatic

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

Ultrasound Imaging of the Thoracic and Abdominal Aorta in Mice to Determine Aneurysm Dimensions

Contemporary high-resolution ultrasound instruments have sufficient resolution to facilitate the measurement of mouse aortas. These instruments have been widely used to measure aortic dimensions in mouse models of aortic aneurysms. Aortic aneurysms are defined as permanent dilations of the aorta, which occur most frequently in the ascending and abdominal regions. Sequential measurements of aortic dimensions by ultrasound are the principal approach for assessing the development and progression of aortic aneurysms in vivo. Although many reported studies used ultrasound imaging to measure aortic diameters as a primary endpoint, there are confounding factors, such as probe position and cardiac cycle, that may impact the accuracy of data acquisition, analysis, and interpretation. The purpose of this protocol is to provide a practical guide on the use of ultrasound to measure the aortic diameter in a reliable and reproducible manner. This protocol introduces the preparation of mice and instruments, the acquisition of appropriate ultrasound images, and data analysis.

Ultrasound imaging has become a common modality to determine the luminal dimensions of thoracic and abdominal aortic aneurysms in mice. This protocol describes the procedure to acquire reliable and reproducible two-dimensional ultrasound images of the ascending and abdominal aorta in mice.

Ecografia da Aorta torácica e Abdominal em ratos para determinar as dimensões de aneurisma

Contemporary high-resolution ultrasound instruments have sufficient resolution to facilitate the measurement of mouse aortas. These instruments have been ...