Os autores gostariam de agradecer a John Marston para especialista em animais de criação e Marco A. Dr. Passini para assistência técnica nas fases iniciais deste projeto. Este trabalho foi financiado por subvenções dos Institutos Nacionais da Saúde para CLL (R01NS41584; R01HD054413).

1. Injeção intracerebroventricular <ol><li> O primeiro passo é a preparação das soluções estoque de injeção; estas soluções são vetor viral, o DNA do plasmídeo, drogas, e deve ser injetado sob condições estéreis. </li><li> Misture um título desejado do vetor viral (total mL 5-7) com 0,05% w / v azul de tripano em PBS para a visualização do local da injeção. </li><li> Solução de DNA plasmidial (5 total de l mL) contém D-(+)-glicose a 20% (w / v) (1 mL), azul de tripano (0,05%) PBS (1 mL), plasmídeo (~ 5 ~ g / L ~ ) (2 ~ L), e 2,5 kDa linear PEI homopolímero (150 mm) (1 ~ L). </li><li> Imobilizar o PND dois recém-nascidos através de crio-anestesia por 1-2 minutos. </li><li> A agulha usada para esta injeção é uma micro-litros micropipeta de vidro calibrado esterilizados que é anexado a uma seringa de 3 mL 3ml Hamilton através de um tubo longo. </li><li> Quebre a ponta da agulha (com espátula) para ajustar para 2 milímetros de penetração no crânio. Coloque a agulha na diagonal no tubo de microcentrífuga contendo a solução de injeção. Carregue a solução de injeção na agulha puxando cuidadosamente o êmbolo da seringa. </li><li> Após a absorção da solução, desassociar a seringa do tubo; puxar o êmbolo até mais longe e, em seguida, anexar a agulha novamente. </li><li> Segure a agulha na mão direita entre o polegar eo dedo indicador e coloque a seringa entre os dedos médio e anelar com o êmbolo tocar a palma da mão direita. </li><li> Segure o rato imobilizado firmemente pela pele atrás da cabeça usando a mão esquerda e coloque em uma luz de fibra ótica para iluminar estruturas anatômicas relevantes que podem ser usados ​​como um guia. </li><li> Inserir a agulha 2 mm de profundidade, perpendicular à superfície do crânio, em um local de aproximadamente 0,25 mm lateral à sutura sagital e 0,50-0,75 milímetros rostral à sutura coronária neonatal (Figura 1A). Em seguida, empurre o êmbolo usando a palma da mão direita de forma muito lenta e cuidadosamente. Monitor para vasos rompidos ou inchaço facial. </li><li> Remova a agulha de 15 segundos após a interrupção do movimento de êmbolo para evitar o refluxo. </li><li> Para recuperar, manter os ratos por 5-10 minutos em um recipiente aquecido até que o movimento ea capacidade de resposta geral é restaurado. </li></ol> 2. Injeção intravenosa através da veia temporal / facial <ol><li> A solução a ser injetada deve ser preparado e suplementadas com corante verde em filtrada diluição 1:100 e injetado em condições estéreis. </li><li> Anexar um plástico pequeno luer para o fim de uma seringa de vidro de 100 mL Hamilton. Ao luer, anexar a 33 gauge agulha hipodérmica 0,25 polegadas. Assegurar que todas as partes estão bem conectados. </li><li> Carregar a seringa com o volume a ser injetado, garantindo que não há ar na seringa como a injeção de ar para dentro do navio é letal. Muitas vezes, é útil para pipeta o volume a ser injetado até um pedaço de parafilme. Isto permite a visualização clara de absorção da solução para a seringa. </li><li> A Visão Transilluminator Wee é usado para visualizar facilmente a veia temporal superficial, ou veia facial, no recém-nascido (Figura 2A). Antes da injecção, segura o recém-nascido para o transiluminador com fita cirúrgica. Gaze deve ser colocado entre o recém-nascido e da fita para evitar que a fita de danificar a pele do animal. Seguro do animal para o transiluminador de lado, garantindo que a fita não impede a respiração. Pescoço do neonato deve ser suavemente girado de modo que a veia facial é facilmente visível eo nariz deve ser gravado para estabilizar a cabeça. </li><li> Usando uma lupa headband 2.25X, para facilitar a visualização, insira lentamente a agulha na veia. A veia é muito superficial para que a agulha deve permanecer visível sob a pele. </li><li> Infundir lentamente o volume de solução na veia. O corante verde permite a fácil visualização da injeção. </li><li> Aguarde 15 segundos antes de remover a agulha como há uma defasagem entre o deprimente totalmente êmbolo da seringa e da expulsão da solução restante devido ao furo de agulha extremamente estreito. </li><li> Depois de remover a agulha, use uma gaze para aplicar pressão no local da injeção até que a hemorragia cessa. </li><li> Monitorar o recém-nascido para os sinais de aflição. Após uma injecção adequada, sem angústia manifesta devem ser observadas. O recém-nascido deve ser dado a cerca de 5 minutos para se recuperar antes de ser devolvido para a jaula. </li><li> Lave a unidade de agulha / seringa com PBS entre injeções de sangue na agulha rapidamente entupi-lo devido a furo pequeno. </li></ol> 3. Resultados representativos: ICV injecção: O cérebro pode ser colhida em diferentes pontos do tempo pós-injeção e visualizados para demonstrar técnica de injeção de sucesso. Se o corante não é adicionado à solução injectável, será difícil para verificar a precisão do emprojecção. Injeção adequada de um dos ventrículos vai permitir a distribuição do azul tripan no lado do cérebro injetados cerca de 10-15 minutos após a injecção (Figura 1B). A distribuição uniforme de azul de tripano em ambos os hemisférios direito e esquerdo cerebral e os bulbos olfativos serão visíveis cerca de 60 minutos após a injeção (Figura 1C). Isto é devido à conectividade dos ventrículos cerebrais que irá permitir a difusão do corante azul para o ventrículo adjacente. Injeções precisas também pode ser visualizado pela dispersão do corante azul no canal central da coluna rostral aproximadamente dentro de 12 horas pós-injeção (Figura 1D). Injeções imprecisos podem ser distinguidos pela ausência de cor azul em hemisférios cerebrais. Neste caso, a profundidade da agulha não foi suficiente ea solução de injeção, provavelmente, distribuído sob a pele. Uma possibilidade alternativa é que a agulha penetrou muito profundamente no cérebro, assim, passando para além do ventrículo ea solução é esvaziado sob os ventrículos cerebrais. IV injeção: injeção veia precisa e eficiente temporal / facial podem ser visualizados imediatamente após a injeção. Como a solução é injetada, o corante verde permite a visualização da solução que entram e que flui através da veia facial (Figura 2A). Além disso, a cor da pele alterada do mouse será observado após a injecção. Cor normal do neonato rosa é convertido em verde, devido à presença de corante alimentar verde na solução de injeção (Figura 2B). A extensão da mudança de cor verde observado no recém-nascido é dependente da concentração de corante utilizado. Para visualização simples de injeção e durante um período de prática, uma diluição de 1:50 é recomendado. No entanto, o tom de pele dramaticamente alterada muitas vezes resulta em que o filhote ser rejeitado pela mãe e, portanto, a remoção do corante ou uma concentração significativamente reduzidos deve ser considerada durante os procedimentos experimentais. Uma injeção imprecisas irá resultar no acúmulo de corante verde sob a pele no local da injeção. Injeção incompleta, que ocorre quando a abertura da agulha não está totalmente inserido dentro da veia, é visto quando alguma solução fluxos na veia e alguns se acumula sob a pele. Se isso for constatado, a agulha deve ser inserida mais para o navio. <img src="/files/ftp_upload/2968/2968fig1.jpg" alt="Figura 1"/> Figura 1. Demonstração de injeções ICV sucesso em PDN2 camundongos. A esquemática) de locais de injecção utilizado em injeções ICV para os ventrículos. B) Cérebro de ICV Pup injetado com azul de tripano em PBS em ventrículo esquerdo, foto tirada 15 minutos após a injeção. C ) Cérebro do ICV Pup injetado com azul de tripano em PBS no ventrículo esquerdo, foto tirada 60 minutos após a injeção. D) Rostral centrais canal espinhal é mostrado na ICV filhote injetado com azul de tripano em PBS no ventrículo esquerdo, foto tirada 12 horas após a injeção. <img src="/files/ftp_upload/2968/2968fig2.jpg" alt="Figura 2"/> Figura 2. Demonstração de injeções de sucesso na IV PDN2 camundongos. A esquemática) da veia facial utilizado para injeções IV. B) IV injetado Pup com corante verde em PBS em comparação com não-injetada ninhada, Foto tirada imediatamente após a injeção.

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Pesquisa utilizando modelos de ratos da doença muitas vezes exige a administração de medicamentos ou outras substâncias para recém-nascidos. Neste vídeo, demonstramos o passo-a-passo os procedimentos que envolvem dois tipos de estratégias de injeção que pode ser usado para atingir o SNC: 1) injeção direta no sistema nervoso central utilizando injeção intracerebroventricular (ICV), ou 2) injeção IV visando a / temporal veia facial. O timing destas injeções é de grande importância. Desde que as injeçõ...

<table border="1"><tbody><tr><th> Nome do reagente </th><th> Companhia </th><th> Número de catálogo </th><th> Comentários (opcional) </th></tr><tr><td> Verde Alimentos Dye </td><td> McCormick </td><td> n / a </td><td> Deve ser filtrado </td></tr><tr><td> Hamilton Seringa de vidro (100 mL) </td><td> Sigma Aldrick </td><td> 20702 </td><td></td></tr><tr><td> Tópico LuerMxF Estilo Nylon Branco </td><td> Peças pequenas, Inc. </td><td> VPLF-LC78-1-25 </td><td></td></tr><tr><td> Agulhas hipodérmicas calibre fino </td><td> Popper </td><td> 7111 </td><td> Tamanho: 33 (SWG) x ¼ &quot;(6,35 MM) </td></tr><tr><td> Transilluminator Visão Wee </td><td> Respironics </td><td> 1017920 </td><td></td></tr><tr><td> 2.25X Headband Lupa </td><td> MagEyes </td><td> Modelo No. 5 </td><td> Selecione a ampliação para atender as preferências individuais </td></tr></tbody></table>

delivery of therapeutic agents through intracerebroventricular (icv) and intravenous (iv) injection in mice

Apesar do papel protetor que barreira hematoencefálica desempenha na proteção do cérebro, que limita o acesso ao sistema nervoso central (SNC), que na maioria das vezes resulta em falha da terapêutica potencial projetado para 1,2 doenças neurodegenerativas. Doenças neurodegenerativas como a Atrofia Muscular Espinhal (SMA), em que os neurônios motores inferiores são afetados, pode beneficiar muito com a introdução de agentes terapêuticos para o CNS. O objetivo deste vídeo é demonstrar dois paradigmas de injecção diferentes para entregar materiais terapêuticos em ratos neonatal logo após o nascimento. Um desses métodos é injetar diretamente cerebral ventrículos laterais (intracerebroventricular) que resulta na entrega de materiais para o sistema nervoso central através do fluido cerebrospinal 3,4. O segundo método é uma injeção de veia temporal (intravenosa) que podem introduzir terapêutica diferente para o sistema circulatório, levando a administração sistêmica incluindo os 5 CNS. Transdução generalizada do SNC é possível se um vetor viral adequada e sorotipo viral é utilizado. Visualização e utilização da veia temporal para injeção é viável até dia pós-natal 6. No entanto, se o material entregue é objetivo de atingir o sistema nervoso central, essas injeções deve ocorrer enquanto a barreira hematoencefálica é mais permeável devido a seu status imaturos, de preferência antes do dia pós-natal 2. A barreira cérebro-sangue totalmente desenvolvido limita bastante a eficácia da administração intravenosa. Ambos os sistemas de entrega são simples e eficaz uma vez que a aptidão cirúrgica seja alcançado. Eles não requerem qualquer dispositivo cirúrgica extensa e pode ser realizada por uma única pessoa. No entanto, estas técnicas não são sem desafios. A pequena dimensão do pós-parto dia 2 filhotes e os subseqüentes áreas-alvo pequenas podem fazer as injeções de difícil execução e, inicialmente, um desafio para replicar.

Watch this Scientific Journal Video about Delivery of Therapeutic Agents Through Intracerebroventricular ICV and Intravenous IV Injection in Mice at JoVE.com

Delivery of Therapeutic Agents Through Intracerebroventricular ICV and Intravenous IV Injection in Mice

Este artigo demonstra dois métodos muito diferentes de injecção: 1) para o cérebro (intracerebroventricular) e 2) sistêmica (intravenosa) para introduzir a agentes terapêuticos para o sistema nervoso central de camundongos recém-nascidos.

Entrega de agentes terapêuticos Através intracerebroventricular (ICV) e injecção intravenosa (IV) em ratos

Despite the protective role that blood brain barrier plays in shielding the brain, it limits the access to the central nervous system (CNS) which most ...

delivery-therapeutic-agents-through-intracerebroventricular-icv

Research

JoVE Journal

Medicine

Delivery of Therapeutic Agents Through Intracerebroventricular (ICV) and Intravenous (IV) Injection in Mice

58.7K visualizações.  University of Missouri. Este artigo demonstra dois métodos muito diferentes de injecção: 1) para o cérebro (intracerebroventricular) e 2) sistêmica (intravenosa) para introduzir a agentes terapêuticos para o sistema nervoso central de camundongos recém-nascidos.

Vídeo: Delivery of Therapeutic Agents Through Intracerebroventricular ICV and Intravenous IV Injection in Mice

Orthotopic Xenografting of Human Luciferase-Tagged Malignant Peripheral Nerve Sheath Tumor Cells for in vivo Testing of Candidate Therapeutic Agents

Although in vitro screens are essential for the initial identification of candidate therapeutic agents, a rigorous assessment of the drug's ability to inhibit tumor growth must be performed in a suitable animal model. The type of animal model that is best for this purpose is a topic of intense discussion. Some evidence indicates that preclinical trials examining drug effects on tumors arising in transgenic mice are more predictive of clinical outcome1and so candidate therapeutic agents are often tested in these models. Unfortunately, transgenic models are not available for many tumor types. Further, transgenic models often have other limitations such as concerns as to how well the mouse tumor models its human counterpart, incomplete penetrance of the tumor phenotype and an inability to predict when tumors will develop.
Consequently, many investigators use xenograft models (human tumor cells grafted into immunodeficient mice) for preclinical trials if appropriate transgenic tumor models are not available. Even if transgenic models are available, they are often partnered with xenograft models as the latter facilitate rapid determination of therapeutic ranges. Further, this partnership allows a comparison of the effectiveness of the agent in transgenic tumors and genuine human tumor cells. Historically, xenografting has often been performed by injecting tumor cells subcutaneously (ectopic xenografts). This technique is rapid and reproducible, relatively inexpensive and allows continuous quantitation of tumor growth during the therapeutic period2. However, the subcutaneous space is not the normal microenvironment for most neoplasms and so results obtained with ectopic xenografting can be misleading due to factors such as an absence of organ-specific expression of host tissue and tumor genes. It has thus been strongly recommended that ectopic grafting studies be replaced or complemented by studies in which human tumor cells are grafted into their tissue of origin (orthotopic xenografting)2. Unfortunately, implementation of this recommendation is often thwarted by the fact that orthotopic xenografting methodologies have not yet been developed for many tumor types.
Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive sarcomas that occur sporadically or in association with neurofibromatosis type 13and most commonly arise in the sciatic nerve4. Here we describe a technically straightforward method in which firefly luciferase-tagged human MPNST cells are orthopically xenografted into the sciatic nerve of immunodeficient mice. Our approach to assessing the success of the grafting procedure in individual animals and subsequent non-biased randomization into study groups is also discussed.

Orthotopic Xenografting of Human Luciferase-Tagged Malignant Peripheral Nerve Sheath Tumor Cells for in vivo Testing of Candidate Therapeutic Agents

A method for reliably grafting luciferase-tagged human malignant peripheral nerve sheath tumor cells into the sciatic nerve of immunodeficient mice is described. The use of bioluminescence imaging to demonstrate proper establishment of tumor grafts and criteria for random segregation of animals into study groups are also discussed.

Ortotópico do xeno-Human-luciferase Tagged maligna dos nervos periféricos Células Tumorais Bainha para In vivo Teste de Agentes Terapêuticos candidatos

Although in vitro screens are essential for the initial identification of candidate therapeutic agents, a rigorous assessment of the drug's ability to ...

Medicina

Slow-release Drug Delivery through Elvax 40W to the Rat Retina: Implications for the Treatment of Chronic Conditions

Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these diseases. Chronic retinal diseases such as retinal oedema or neovascularization usually require multiple intraocular injections to effectively treat the condition. However, the risks associated with these injections increase with repeated delivery of the drug. Therefore, alternative delivery methods need to be established in order to minimize the risks of reinjection. Several other investigations have developed methods to deliver drugs over extended time, through materials capable of releasing chemicals slowly into the eye. In this investigation, we outline the use of Elvax 40W, a copolymer resin, to act as a vehicle for drug delivery to the adult rat retina. The resin is made and loaded with the drug. The drug-resin complex is then implanted into the vitreous cavity, where it will slowly release the drug over time. This method was tested using 2-amino-4-phosphonobutyrate (APB), a glutamate analogue that blocks the light response of the retina. It was demonstrated that the APB was slowly released from the resin, and was able to block the retinal response by 7 days after implantation. This indicates that slow-release drug delivery using this copolymer resin is effective for treating the retina, and could be used therapeutically with further testing.

This paper details how Elvax 40W can be used as a slow-release method for drug delivery to the adult rat retina. The protocol for preparing, loading, and delivering the drug-resin complex to the eye is described.

De liberação lenta Drug Delivery através Elvax 40W para o Rat Retina: implicações para o tratamento de condições crônicas

Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these ...

Ultrasound-guided Transthoracic Intramyocardial Injection in Mice

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. Experiments involving myocardial injection are currently performed by direct surgical access through a thoracotomy. While convenient when performed at the time of another experimental manipulation such as coronary artery ligation, the need for an invasive procedure for intramyocardial delivery limits potential experimental designs. With ever improving ultrasound resolution and advanced noninvasive imaging modalities, it is now feasible to routinely perform ultrasound-guided, percutaneous intramyocardial injection. This modality efficiently and reliably delivers agents to a targeted region of myocardium. Advantages of this technique include the avoidance of surgical morbidity, the facility to target regions of myocardium selectively under ultrasound guidance, and the opportunity to deliver injectate to the myocardium at multiple, predetermined time intervals. With practiced technique, complications from intramyocardial injection are rare, and mice quickly return to normal activity on recovery from anesthetic. Following the steps outlined in this protocol, the operator with basic echocardiography experience can quickly become competent in this versatile, minimally invasive technique.

Echocardiography-guided percutaneous intramyocardial injection represents an efficient, reliable, and targetable modality for the delivery of gene transfer agents or cells into the murine heart. Following the steps outlined in this protocol, the operator can quickly become competent in this versatile, minimally invasive technique.

Guiada por ultra-som transtorácica intramiocárdico Injection em Ratos

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. ...

Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine

To date, many pharmacological agents used to treat or prevent arrhythmias in open-heart cases create undesired systemic side effects. For example, antiarrhythmic drugs administered intravenously can produce drops in systemic pressure in the already compromised cardiac patient. While performing open-heart procedures, surgeons will often either create a small port or form a pericardial cradle to create suitable fields for operation. This access yields opportunities for target pharmacological delivery (antiarrhythmic or ischemic preconditioning agents) directly to the myocardial tissue without undesired side effects.
We have developed a swine model for testing pharmacological agents for target delivery within the pericardial fluid. While fully anesthetized, each animal was instrumented with a Swan-Ganz catheter as well as left and right ventricle pressure catheters, and pacing leads were placed in the right atrial appendage and the right ventricle. A medial sternotomy was then performed and a pericardial access cradle was created; a plunge pacing lead was placed in the left atrial appendage and a bipolar pacing lead was placed in the left ventricle. Utilizing a programmer and a cardiac mapping system, the refractory period of the atrioventricular node (AVN), atria and ventricles was determined. In addition, atrial fibrillation (AF) induction was produced utilizing a Grass stimulator and time in AF was observed. These measurements were performed prior to treatment, as well as 30 min&#160;and 60 min&#160;after pericardial treatment. Additional time points were added for selected studies. The heart was then cardiopleged and reanimated in a four chamber working mode. Pressure measurements and function were recorded for 1 hr after reanimation. This treatment strategy model allowed us to observe the effects of pharmacological agents that may decrease the incidence of cardiac arrhythmias and/or ischemic damage, during and after open-heart surgery.

We have developed a swine model for the target delivery of pharmacological agents within the pericardial space/fluid. Using this approach, the relative benefits of administered agents on induced atrial fibrillation, relative refractory periods and/or ischemic protection can be investigated.

Testando a eficácia de agentes farmacológicos em um Delivery Model Pericárdica alvo na Suína

To date, many pharmacological agents used to treat or prevent arrhythmias in open-heart cases create undesired systemic side effects. For example, ...

Disposable Dosators for Pulmonary Insufflation of Therapeutic Agents to Small Animals

Development of new therapeutic products requires efficacy testing in an animal model. The pulmonary route of administration can be utilized to deliver drugs locally and systemically. Evaluation of dry powder aerosols necessitates an efficient dispersion mechanism to maintain high concentrations in an exposure chamber or for direct endotracheal administration. While solutions exist to expose animals by passive inhalation to dry powder aerosols, most require masses of powder in large excess of the dose delivered. This precludes conducting early feasibility studies as insufficient drug is available at the research or early development stage to support the dose delivery requirements for conventional aerosol delivery systems. When designing an aerosol drug product, aerodynamic performance can relate directly to delivery efficiency and efficacy. Dispersion of powder into an aerosol requires energy input sufficient to overcome interparticulate forces, and particle engineering approaches can substantially improve aerosol performance. We have developed a dispersion system (dosator) which can aerosolize engineered dry powder aerosols efficiently for the purpose of direct pulmonary insufflation, dispersion into an exposure system or generation for analytical purposes.

During development of drugs for pulmonary delivery, it is necessary to evaluate pharmacokinetics and efficacy in an animal model. We present a method to build a disposable aerosol dispersion system from of-the-shelf components that can be used to administer intrapulmonary dry powder aerosol to rodents.

Doseadores descartável para Pulmonar insuflação de agentes terapêuticos para Pequenos Animais

Development of new therapeutic products requires efficacy testing in an animal model. The pulmonary route of administration can be utilized to deliver ...

Intranasal Delivery of Therapeutic Stem Cells to Glioblastoma in a Mouse Model

The intrinsic tropism towards brain malignancies renders stem cells as promising carriers of therapeutic agents against malignant tumors. The delivery of therapeutic stem cells via the intranasal route is a recently discovered alternative strategy, with strong potential for clinical translation, due to its non-invasive nature compared to intracranial implantation or delivery via systemic routes. The lack of blood brain barrier further strengthens the therapeutic potential of stem cells undergoing intranasal brain entry. This article summarizes the essential techniques utilized in our studies and outlines the basic principles of intranasal strategy for stem cell delivery using a mouse model of intracranial glioma xenografts. We demonstrate the optimized procedures that generate consistent and reproducible results with specific predetermined experimental parameters and offer guidelines for streamlined work flow that ensure efficient execution and reliable experimental outcome. The article is designed to serve as a baseline for further experimental customization based on hypothesis, stem cell types, or tumor specifics.

Stem cells are promising therapeutic carriers to treat brain tumors due to their intrinsic tumor tropism. Non-invasive intranasal stem cell delivery bypasses the blood brain barrier and demonstrates strong potential for clinical translation. This article summarizes the basic principles of intranasal stem cell delivery in a mouse model of glioma.

Entrega intranasal de células-tronco terapêuticas para Glioblastoma em um modelo de mouse

The intrinsic tropism towards brain malignancies renders stem cells as promising carriers of therapeutic agents against malignant tumors. The delivery of ...

A Rat Carotid Artery Pressure-Controlled Segmental Balloon Injury with Periadventitial Therapeutic Application

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the luminal surface area in arteries thereby reducing adequate blood flow to organs and distal tissues. Clinically, revascularization procedures such as balloon angioplasty with or without stent placement aim to restore blood flow. Although these procedures reestablish blood flow by reducing plaque burden, they damage the vessel wall, which initiates the arterial healing response. The prolonged healing response causes arterial restenosis, or re-narrowing, ultimately limiting the long-term success of these revascularization procedures. Therefore, preclinical animal models are integral for analyzing the pathophysiological mechanisms driving restenosis, and provide the opportunity to test novel therapeutic strategies. Murine models are cheaper and easier to operate on than large animal models. Balloon or wire injury are the two commonly accepted injury modalities used in murine models. Balloon injury models in particular mimic the clinical angioplasty procedure and cause adequate damage to the artery for the development of restenosis. Herein we describe the surgical details for performing and histologically analyzing the modified, pressure-controlled rat carotid artery balloon injury model. Additionally, this protocol highlights how local periadventitial application of therapeutics can be used to inhibit neointimal hyperplasia. Lastly, we present light sheet fluorescence microscopy as a novel approach for imaging and visualizing the arterial injury in three-dimensions.

The rat carotid artery balloon injury mimics the clinical angioplasty procedure performed to restore blood flow in atherosclerotic vessels. This model induces the arterial injury response by distending the arterial wall, and denuding the intimal layer of endothelial cells, ultimately causing remodeling and an intimal hyperplastic response.

Uma lesão de balão segmental controlada por pressão da artéria de rato com aplicação terapêutica periadventicional

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the ...

Intratracheal Administration of Dry Powder Formulation in Mice

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper introduces a noninvasive method of intratracheal delivery of dry powder formulation in mice. A dry powder loading device that consists of a 200 &#181;L gel loading pipette tip connected to an 1 mL syringe via a three-way stopcock is presented. A small amount of dry powder (1-2 mg) is loaded into the pipette tip and dispersed by 0.6 mL of air in the syringe. Because pipette tips are disposable and inexpensive, different dry powder formulations can be loaded into different tips in advance. Various formulations can be evaluated in the same animal experiment without device cleaning and dose refilling, thereby saving time and eliminating the risk of cross-contamination from residual powder. The extent of powder dispersion can be inspected by the amount of powder remaining in the pipette tip. A protocol of intubation in mouse with a custom-made light source and a guiding cannula is included. Proper intubation is one of the key factors that influences the intratracheal delivery of dry powder formulation to the deep lung region of the mouse.

Dry powder formulations for inhalation have great potential in treating respiratory diseases. Before entering human studies, it is necessary to evaluate the efficacy of the dry powder formulation in preclinical studies. A simple and noninvasive method of the administration of dry powder in mice through the intratracheal route is presented.

Administração Intratraqueal de Formulação de Pó Seco em Camundongos

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper ...

Decocção de Liujunzi: um tratamento eficaz para a prevenção de UC-CRC

Establishment of Coloproctitis Cancer Model in Mice and Evaluation of Therapeutic Effect of Chinese Medicine

Colorectal cancer (CRC) is a common malignancy of the digestive system and has become the third most common malignancy worldwide and the second leading cause of malignancy-related death. Ulcerative coloproctitis (UC) is a precancerous lesion, and UC-associated CRC (UC-CRC) is the most common subtype of CRC. Therefore, a reasonable UC-CRC model is the cornerstone and guarantee of new drug development. Traditional Chinese medicine (TCM) has been widely used in the treatment of UC-CRC due to its good efficacy. As a classic tonic prescription of TCM, Liujunzi decoction (LJZD) has been widely used in the treatment of UC-CRC. In this study, a UC-CRC model was established by combining azomethane and dextran sulfate sodium, and the LJZD was administered. The data confirmed that LJZD can effectively inhibit cancer transition in UC-CRC by using mouse body weight, colorectal length, pathological and inflammatory factors, colorectal barrier function, and cancer markers. This protocol provides a system for evaluating the efficacy of TCM in the prevention and treatment of UC-CRC.

Autor em destaque: Decocção de Liujunzi como tratamento tradicional chinês para câncer de coloproctite

This protocol provides a mouse model of ulcerative coloproctitis-associated colorectal cancer induced by azomethane combined with dextran sulfate sodium. The model was used to evaluate the efficacy of traditional Chinese medicine compounds in the prevention and treatment of colorectal cancer.

Estabelecimento do Modelo de Câncer de Coloproctite em Camundongos e Avaliação do Efeito Terapêutico da Medicina Chinesa

Colorectal cancer (CRC) is a common malignancy of the digestive system and has become the third most common malignancy worldwide and the second leading ...