Gli autori ringraziano Christiane Pahrmann per la sua assistenza tecnica e istologia performanti.

<html> Topi BALB / c per un peso minimo di 20 g in età da 8 a 12 settimane sono acquistati da Charles River (Sandhofer Weg 7, D-97633 Sulzfeld). I topi sono alloggiati in condizioni convenzionali, alimentati pellet del mouse standard e acqua ad libitum. Anestetizzare mouse con isoflurano (2%) con una camera di induzione. <ol><li> Radere la zona del collo e il lato sinistro della gabbia toracica e disinfettare con l&#39;80% di etanolo. </li><li> Posizionare il mouse sul dorso e posto una maschera sul suo naso e la bocca per mantenere l&#39;anestesia. </li><li> Verificare i riflessi pizzicare la coda e le zampe posteriori per essere sicuri che il mouse è sufficiente anesthesized. </li><li> In vista microscopico eseguire una incisione mediana che separa la cervicale, i muscoli della pelle e tessuto che copre la trachea. </li><li> Quando la trachea è esposto tagliare un piccolo foro nel tessuto tra due anelli cartuccia di sotto della glottide per inserire il tubo endotracheale (Figura 1). Inserire il tubo endotracheale tenendo la parte craniale della trachea utilizzando micro forecepts chirurgico. Controllare il movimento del torace per essere sicuri che entrambi i polmoni sono ben ventilato. </li><li> La frequenza respiratoria (RR) dovrebbero essere circa 110 al minuto, con una pressione inspiratoria di 17 a 18 centimetri H 2 O. Girare il mouse con cura, situata sul lato destro, verso il lato sinistro. Eseguire una toracotomia leftsided tra il 3 e il 4 ° costola, e sezionare il tessuto muscolare e con attenzione, usando un Cauter per prevenire le emorragie. </li><li> Aprire il torace con attenzione, una volta che il torace è aperto, trovare il cuore, senza toccare il polmone con oggetti appuntiti. Ora rimuovere la parte del sacco pericardico che copre il cuore. </li><li> Il LAD si trova tra l&#39;arteria polmonare e l&#39;atrio sinistro. Utilizzare un Prolene 8-0 sutura (Ethicon, Norderstedt) per legare la LAD prossimale con una sutura singola (Figura 2). </li><li> Posizionare un drenaggio toracico (28G, catetere venale), tra il 4 e il 5 ° costola. </li><li> Chiudere l&#39;incisione del torace in strati, con 6-0 punti di sutura Prolene esecuzione (Ethicon, Norderstedt, Germania) per adattare le costole e suture Prolene 4-0 in esecuzione (Ethicon, Norderstedt, Germania) per chiudere la pelle. </li><li> Scolate il torace con l&#39;aiuto di una siringa da 2 ml con cura (Figura 3). Posizionare il mouse sul dorso. Ora prendete il tubo endotracheale e adeguare le anelli tracheali con una sola cartuccia punto singolo con 7-0 punti di sutura Prolene (Ethicon, Norderstedt, Germania). </li><li> Posizionare la maschera del mouse e chiudere la pelle con Prolene 4-0 esecuzione suture (Ethicon, Norderstedt, Germania). </li></ol> Validazione Ci sono diverse possibilità di confermare il successo della LAD-legatura. Il test della troponina può essere eseguito 6 a 18 ore dopo l&#39;intervento chirurgico, usando soltanto 150 litri di sangue, senza la necessità di eutanasia degli animali. Il sangue viene applicata a un kit personalizzato di test della troponina (T TROP sensibili, Roche, Mannheim) (Figura 4). Troponina è una proteina regolatrice della filamenti di actina della cellula muscolare, ci sono isotipi differenti nei tre tipi di muscolo. La cTnI e cTnT isotipi si trovano nel cuore e sono uscito nel danno tissutale. Il test standardizzato per la troponina T (cTnT) si basa su due specifici anticorpi monoclonali cuore, uno trappole della troponina nel campione di sangue, il secondo è un indicatore. La zona infartuata può essere identificato macroscopicamente dopo 3 giorni (Figura 5). TTC (2,3,5-trifeniltetrazolio cloruro) colorazione dei tessuti misure di viabilità per valutare dimensioni dell&#39;infarto. Evans colorante blu (1,5%, 1,0 ml) in tampone fosfato salino (PBS) viene iniettato nella cavità ventricolare sinistra per misurare l&#39;area del miocardio ischemico. Il mouse è eutanasia e il cuore viene raccolto e sezionato in fette. Le fette di tessuto sono incubati in 1% di soluzione di TTC PBS, pH 7,4 a 37 ° C per 20 min. I tessuti sono fissati nel 10% PBS-formalina tamponata durante la notte a 2-8 ° C. TTC viene somministrato ex vivo per la tintura blu di Evans-negativi aree (Figura 6). Per istologia il mouse deve essere eutanasia e il cuore deve essere integrato per ulteriori elaborazioni. Dopo l&#39;esecuzione di sezioni di paraffina, le diapositive sono macchiati con H &amp; E (ematossilina e eosina) o tricromica di visualizzare tessuto fibrotico (Figura 7). <img src="/files/ftp_upload/1438/1438fig1.jpg" alt="Figura 1" /> Figura 1: tubo tracheale. 1A: Esposto trachea, dopo ventrale incisione cervicale. 1B: Trachea è aperto due anelli di cartilagine caudale alla laringe. 1C: tubo tracheale viene inserito nella trachea. <img src="/files/ftp_upload/1438/1438fig2.jpg" alt="Figura 2" /> Figura 2: Il cuore è esposto attraverso una toracotomia sinistra lato, il ragazzo è legato. t &quot;&gt; <img src="/files/ftp_upload/1438/1438fig3.jpg" alt="Figura 3" /> Figura 3: Dopo il torace è chiuso, uno scarico pleura viene eseguita. Il mouse è ancora sotto anestesia. <img src="/files/ftp_upload/1438/1438fig4.jpg" alt="Figura 4" /> Figura 4: Due linee appaiono dopo pochi minuti quando il test della troponina positivo. <img src="/files/ftp_upload/1438/1438fig5.jpg" alt="Figura 5" /> Figura 5: mostra il cuore espiantato. 5A: vista macroscopico del cuore con l&#39;area ischemica con un colore sbiadito biancastro. 5B: Sezione del cuore infartuato, l&#39;area ischemica mostra in alto a destra.

<ol>
	<li>Atkins, B. Z., Hueman, M. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+cardiomyoplasty+improves+diastolic+properties+of+injured+Heart.">Cellular cardiomyoplasty improves diastolic properties of injured Heart.</a> J Surg Res. 85 (2), 234-242 (1999).</li><li>Jaquet, K., KT, K. r. a. u. s. e. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduction+of+myocardial+scar+size+after+implantation+of+mesenchymal+stem+cells+in+rats:+what+is+the+mechanism.">Reduction of myocardial scar size after implantation of mesenchymal stem cells in rats: what is the mechanism.</a> Stem Cells Dev. 14 (3), 299-309 (2005).</li><li>Joung, B., Kim, I. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bone+marrow+mononuclear+stem+cells+transplanted+in+rat+infarct+myocardium+improved+the+electrical+conduction+without+evidence+of+proarrhythmic+effects.">Bone marrow mononuclear stem cells transplanted in rat infarct myocardium improved the electrical conduction without evidence of proarrhythmic effects.</a> Yonsei Med J. 48 (5), 754-764 (2007).</li></ol>

Finanziamento Il presente studio è stato sostenuto dalla Clinica Universitaria di Amburgo (MK, Donna Abilitazione Grant), DFG (SS, SCHR992/3-1), ISHLT (TD, Research Award 2009). Dichiarazione Tutti gli animali hanno ricevuto assistenza umana in conformità ai principi di cura degli animali da laboratorio, gli esperimenti sugli animali sono stati eseguiti secondo le linee guida e regolamenti stabiliti dalla Società Nazionale per la ricerca medica e la Guida per la cura e l&#39;uso di animali da laboratorio pubblicato dalla National Institutes of Health (National Institutes of Health pubblicazione 85-23, revisione 1985). Tutti gli animali sono stati ottenuti da Charles River Laboratories (Sulzfeld, Germania) e sono stati mantenuti in strutture di cura degli animali della Clinica Universitaria di Amburgo Eppendorf. Gli animali hanno ricevuto standard di cibo e acqua ad libitum.

In sintesi, questo video visualizza la LAD-legatura modello passo-passo e identifica LAD-legature nei topi, come gli interventi chirurgici facilmente realizzabile.

lad-ligation: a murine model of myocardial infarction

Modelli di ricerca di infarto e ischemia miocardica sono essenziali per studiare i processi acuti e cronici pathobiological e fisiopatologici in ischemia miocardica e di sviluppare e ottimizzare il trattamento futuro. Due diversi metodi di creazione di ischemia miocardica sono svolte nei roditori da laboratorio. Il primo metodo è quello di creare crio infarto, una tecnica veloce ma impreciso, dove viene applicato un crio-pen sulla superficie del cuore (1-3). Usando questo metodo lo scienziato non può garantire che la crio-cicatrice porta a ischemia, anche una vasta ferita del miocardio è creata che mostra gli effetti collaterali fisiopatologici che non sono legati a infarto del miocardio. Il secondo metodo è la legatura permanente della discendente anteriore sinistra (LAD). Qui il LAD è legatura con un punto singolo, formando una ischemia che può essere visto quasi immediatamente. Chiudendo il LAD, non ulteriormente il flusso di sangue è consentito in quell&#39;area, mentre il tessuto circostante miocardico non è quasi colpito. Questa procedura chirurgica imita gli aspetti pathobiological e fisiopatologici che si verificano in infarto legate ischemia miocardica. Il metodo introdotto in questo video dimostra la procedura chirurgica di un modello di infarto del mouse legando il LAD. Questo modello è conveniente per gli studi pathobiological e fisiopatologiche e sui immunobiologici infarto cardiaco. La tecnica illustrata assicura un&#39;elevata precisione e correla bene con sezioni istologiche.

Watch this Scientific Journal Video about LAD-Ligation: A Murine Model of Myocardial Infarction at JoVE.com

LAD-Ligation: A Murine Model of Myocardial Infarction

Questo video illustra come utilizzare un modello veloce e affidabile per lo studio dei processi fisiopatologici pathobiological e di ischemia miocardica.

LAD-Legatura: un modello murino di infarto miocardico

Research models of infarction and myocardial ischemia are essential to investigate the acute and chronic pathobiological and pathophysiological processes ...

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Universidad de Cartagena UDEC

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44.4K Views.  University Heart Center Hamburg. Questo video illustra come utilizzare un modello veloce e affidabile per lo studio dei processi fisiopatologici pathobiological e di ischemia miocardica.

Video: LAD-Ligation: A Murine Model of Myocardial Infarction

Acute Myocardial Infarction in Rats

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular diseases. Animal models that mimic human cardiac disease, such as myocardial infarction (MI) and ischemia-reperfusion (IR) that induces heart failure as well as pressure-overload (transverse aortic constriction) that induces cardiac hypertrophy and heart failure (Goldman and Tarnavski), are useful models to study cardiovascular disease. In particular, myocardial ischemia (MI) is a leading cause for cardiovascular morbidity and mortality despite controlling certain risk factors such as arteriosclerosis and treatments via surgical intervention (Thygesen). Furthermore, an acute loss of the myocardium following myocardial ischemia (MI) results in increased loading conditions that induces ventricular remodeling of the infarcted border zone and the remote non-infarcted myocardium. Myocyte apoptosis, necrosis and the resultant increased hemodynamic load activate multiple biochemical intracellular signaling that initiates LV dilatation, hypertrophy, ventricular shape distortion, and collagen scar formation. This pathological remodeling and failure to normalize the increased wall stresses results in progressive dilatation, recruitment of the border zone myocardium into the scar, and eventually deterioration in myocardial contractile function (i.e. heart failure). The progression of LV dysfunction and heart failure in rats is similar to that observed in patients who sustain a large myocardial infarction, survive and subsequently develops heart failure (Goldman). The acute myocardial infarction (AMI) model in rats has been used to mimic human cardiovascular disease; specifically used to study cardiac signaling mechanisms associated with heart failure as well as to assess the contribution of therapeutic strategies for the treatment of heart failure. The method described in this report is the rat model of acute myocardial infarction (AMI). This model is also referred to as an acute ischemic cardiomyopathy or ischemia followed by reperfusion (IR); which is induced by an acute 30-minute period of ischemia by ligation of the left anterior descending artery (LAD) followed by reperfusion of the tissue by releasing the LAD ligation (Vasilyev and McConnell). This protocol will focus on assessment of the infarct size and the area-at-risk (AAR) by Evan's blue dye and triphenyl tetrazolium chloride (TTC) following 4-hours of reperfusion; additional comments toward the evaluation of cardiac function and remodeling by modifying the duration of reperfusion, is also presented. Overall, this AMI rat animal model is useful for studying the consequence of a myocardial infarction on cardiac pathophysiological and physiological function.

The rat model of acute myocardial infarction (AMI) is useful to study the consequence of a MI on cardiac pathophysiological and physiological function.

Infarto acuto del miocardio in topi

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular ...

Ricerca

Medicina

Coronary Artery Ligation and Intramyocardial Injection in a Murine Model of Infarction

Mouse models are a valuable tool for studying acute injury and chronic remodeling of the myocardium in vivo. With the advent of genetic modifications to the whole organism or the myocardium and an array of biological and/or synthetic materials, there is great potential for any combination of these to assuage the extent of acute ischemic injury and impede the onset of heart failure pursuant to myocardial remodeling. 
Here we present the methods and materials used to reliably perform this microsurgery and the modifications involved for temporary (with reperfusion) or permanent coronary artery occlusion studies as well as intramyocardial injections. The effects on the heart that can be seen during the procedure and at the termination of the experiment in addition to histological evaluation will verify efficacy. 
Briefly, surgical preparation involves anesthetizing the mice, removing the fur on the chest, and then disinfecting the surgical area. Intratracheal intubation is achieved by transesophageal illumination using a fiber optic light. The tubing is then connected to a ventilator. An incision made on the chest exposes the pectoral muscles which will be cut to view the ribs. For ischemia/reperfusion studies, a 1 cm piece of PE tubing placed over the heart is used to tie the ligature to so that occlusion/reperfusion can be customized. For intramyocardial injections, a Hamilton syringe with sterile 30gauge beveled needle is used. When the myocardial manipulations are complete, the rib cage, the pectoral muscles, and the skin are closed sequentially. Line block analgesia is effected by 0.25% marcaine in sterile saline which is applied to muscle layer prior to closure of the skin. The mice are given a subcutaneous injection of saline and placed in a warming chamber until they are sternally recumbent. They are then returned to the vivarium and housed under standard conditions until the time of tissue collection. At the time of sacrifice, the mice are anesthetized, the heart is arrested in diastole with KCl or BDM, rinsed with saline, and immersed in fixative. Subsequently, routine procedures for processing, embedding, sectioning, and histological staining are performed. 
Nonsurgical intubation of a mouse and the microsurgical manipulations described make this a technically challenging model to learn and achieve reproducibility. These procedures, combined with the difficulty in performing consistent manipulations of the ligature for timed occlusion(s) and reperfusion or intramyocardial injections, can also affect the survival rate so optimization and consistency are critical.

Numerous genetic manipulations and/or intramyocardial injections of genes, proteins, cells, and/or biomaterials are superimposed upon the dimension of time in studies of acute ischemia/ reperfusion injury and chronic remodeling in mice. This video illustrates the microsurgical procedures for ischemia/reperfusion, permanent coronary artery ligation, and intramyocardial injection studies.

Legatura dell&#39;arteria coronarica e di iniezione intramiocardico in un modello murino di infarto

Mouse models are a valuable tool for studying acute injury and chronic remodeling of the myocardium in vivo.  With the advent of genetic modifications to ...

Modified Technique for Coronary Artery Ligation in Mice

Myocardial infarction (MI) is one of the most important causes of mortality in humans1-3. In order to improve morbidity and mortality in patients with MI we need better knowledge about pathophysiology of myocardial ischemia. This knowledge may be valuable to define new therapeutic targets for innovative cardiovascular therapies4. Experimental MI model in mice is an increasingly popular small-animal model in preclinical research in which MI is induced by means of permanent or temporary ligation of left coronary artery (LCA)5. In this video, we describe the step-by-step method of how to induce experimental MI in mice.
The animal is first anesthetized with 2% isoflurane. The unconscious mouse is then intubated and connected to a ventilator for artificial ventilation. The left chest is shaved and 1.5 cm incision along mid-axillary line is made in the skin. The left pectoralis major muscle is bluntly dissociated until the ribs are exposed. The muscle layers are pulled aside and fixed with an eyelid-retractor. After these preparations, left thoracotomy is performed between the third and fourth ribs in order to visualize the anterior surface of the heart and left lung. The proximal segment of LCA artery is then ligated with a 7-0 ethilon suture which typically induces an infarct size ~40% of left ventricle. At the end, the chest is closed and the animals receive postoperative analgesia (Temgesic, 0.3 mg/50 ml, ip). The animals are kept in a warm cage until spontaneous recovery.

The surgical procedure used to induce experimental myocardial infarction in mice begins with left thoracotomy between the third and the fourth ribs in order to visualize the anterior surface of the heart and left lung. The left coronary artery is ligated, the chest is closed and the mouse is allowed to recover spontaneously.

Tecnica modificata di legatura dell&#39;arteria coronarica in Mouse

Myocardial infarction (MI) is one of the most important causes of mortality in humans1-3. In order to improve morbidity and mortality in patients with MI ...

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

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

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

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

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

Permanent Ligation of the Left Anterior Descending Coronary Artery in Mice: A Model of Post-myocardial Infarction Remodelling and Heart Failure

Heart failure is a syndrome in which the heart fails to pump blood at a rate commensurate with cellular oxygen requirements at rest or during stress. It is characterized by fluid retention, shortness of breath, and fatigue, in particular on exertion. Heart failure is a growing public health problem, the leading cause of hospitalization, and a major cause of mortality. Ischemic heart disease is the main cause of heart failure.
Ventricular remodelling refers to changes in structure, size, and shape of the left ventricle. This architectural remodelling of the left ventricle is induced by injury (e.g., myocardial infarction), by pressure overload (e.g., systemic arterial hypertension or aortic stenosis), or by volume overload. Since ventricular remodelling affects wall stress, it has a profound impact on cardiac function and on the development of heart failure. A model of permanent ligation of the left anterior descending coronary artery in mice is used to investigate ventricular remodelling and cardiac function post-myocardial infarction. This model is fundamentally different in terms of objectives and pathophysiological relevance compared to the model of transient ligation of the left anterior descending coronary artery. In this latter model of ischemia/reperfusion injury, the initial extent of the infarct may be modulated by factors that affect myocardial salvage following reperfusion. In contrast, the infarct area at 24 hr after permanent ligation of the left anterior descending coronary artery is fixed. Cardiac function in this model will be affected by 1) the process of infarct expansion, infarct healing, and scar formation; and 2) the concomitant development of left ventricular dilatation, cardiac hypertrophy, and ventricular remodelling.
Besides the model of permanent ligation of the left anterior descending coronary artery, the technique of invasive hemodynamic measurements in mice is presented in detail.

Heart failure is the leading cause of hospitalization and a major cause of mortality. A model of permanent ligation of the left anterior descending coronary artery in mice is applied to investigate ventricular remodelling and cardiac dysfunction post-myocardial infarction. The technique of invasive hemodynamic measurements in mice is presented.

Legatura permanente dell&#39;arteria discendente anteriore sinistra coronarica nei topi: un modello di post-infarto rimodellante miocardico e insufficienza cardiaca

Heart failure is a syndrome in which the heart fails to pump blood at a rate commensurate with cellular oxygen requirements at rest or during stress. It ...

Murine Left Anterior Descending (LAD) Coronary Artery Ligation: An Improved and Simplified Model for Myocardial Infarction

Ischemic heart disease (IHD), or acute coronary syndrome (ACS), is one of the leading causes of death in the United States. IHD is characterized by reduced blood supply to the heart, resulting in the loss of oxygen to and the ensuing necrosis of the heart muscle. The MI model has gained popularity for its use as a short-term ischemia-reperfusion model and a long-term permanent ligation model. Below, we describe a reliable method for the permanent ligation of the LAD. With mouse genetic engineering technology becoming more advanced, and with an increasing availability of quality murine surgical instruments, the mouse has become a popular model for MI surgeries. Our surgical model incorporates the use of an easily reversible anesthetic for the rapid recovery of the mouse; a minimally invasive endotracheal intubation without involving a tracheotomy; and a thoracentesis through the original thoracotomy site without creating an additional incision in the chest, as is done in some other methods, to effectively remove excess blood and air from the chest cavity. This method is comparatively less invasive than other methods, which dramatically reduces surgical and post-surgical complications and mortality and improves reproducibility.

Murine Left Anterior Descending LAD Coronary Artery Ligation: An Improved and Simplified Model for Myocardial Infarction

We provide a reliable method for left anterior descending artery (LAD) ligation in a mouse model. This method is comparatively less invasive than other methods, involving endotracheal intubation, a left-sided thoracotomy approach, and thoracentesis. This method can be used as a model for both acute and chronic myocardial infarction (MI).

Murino discendente anteriore sinistra (LAD) Coronary legatura dell&#39;arteria: una migliore e semplificata del modello di infarto miocardico

Ischemic heart disease (IHD), or acute coronary syndrome (ACS), is one of the leading causes of death in the United States. IHD is characterized by ...

Murine Myocardial Infarction Model using Permanent Ligation of Left Anterior Descending Coronary Artery

Myocardial infarction (MI) and acute coronary diseases are among the most prominent causes of death in population with western lifestyle. The murine models of MI with permanent ligation of left-anterior descending (LAD) coronary artery closely mimics MI in humans. Murine models benefit from the extensive genetic engineering available nowadays. Here we propose a reproducible murine surgical model of myocardial infarction by permanent LAD coronary ligation. Our technique comprises anesthesia with ketamine/xylazine that can be rapidly reversed by administration of an antagonist, intubation without tracheotomy for mechanical-assisted ventilation, ventilation with application of extrinsic positive end-expiratory pressure (PEEP) to avoid alveolar collapse, a thoracotomy method limiting to the minimum surgical lesions made to skeletal muscles, and lung inflation without thoracentesis. This method is sparsely invasive, reproducible and reduces post-surgery mortality and complications.

Herein we describe a surgical procedure showing how to achieve permanent ligation of the left-anterior descending coronary artery in mice. This model is of high relevance to investigate the pathophysiology of myocardial infarction and the concomitant biological processes.

Modello di infarto miocardico Murine utilizzando la legatura permanente dell'arteria coronaria discendente anteriore sinistra

Myocardial infarction (MI) and acute coronary diseases are among the most prominent causes of death in population with western lifestyle. The murine ...

A New Model of Heart Failure Post-Myocardial Infarction in the Rat

Ligation of the left anterior descending (LAD) coronary artery has been widely used to establish the rat model of heart failure (HF) post myocardial infarction (MI). However, the disadvantages of this model include high mortality rate after ligation and larger variations both in the infarct size and the degree of impaired cardiac function. In addition, a ventilator or exteriorization of the heart is indispensable for the previous models, which complicates the procedure during the ligation. In this study, we developed a reliable and reproducible model without the ventilator or exteriorization of the heart by ligating the LAD coronary artery. Four weeks after the procedure, we found that the serum concentrations of CK-MB, NT-proBNP, and Renin, which were used to assist diagnoses of MI and HF, were significantly higher in the MI group compared to the sham group. In contrast, the value of left ventricle ejection fraction (LVEF) in the MI group was obviously less than in the sham group. Furthermore, the infarct size and cardiac fibrosis area were individually confirmed and quantitatively analyzed by TTC staining and Masson's trichrome staining. Smaller variations were found in either infarct size or fibrosis area in the MI group, which helped to develop a reliable and reproducible model of HF post-MI. This new model of HF post-MI in the rat is vital for studying the potential mechanisms of MI and HF. This new method can be used to develop the new drug for treatment of MI and HF in rats by using pharmacological strategies.

We successfully developed a reliable and reproducible model of heart failure post-myocardial infarction in the rat without ventilation or exteriorization of the heart. This simplifies the procedure and benefits the further studies about the potential mechanisms behind the heart failure.

Ligation of the left anterior descending (LAD) coronary artery has been widely used to establish the rat model of heart failure (HF) post myocardial ...

Induction of Myocardial Infarction and Myocardial Ischemia-Reperfusion Injury in Mice

Acute myocardial infarction is a common cardiovascular disease with high mortality. Myocardial reperfusion injury can counteract the beneficial effects of heart reflow and induce secondary myocardial injury. A simple and reproducible model of myocardial infarction and myocardial ischemia-reperfusion injury is a good tool for researchers. Here, a customizable method to create a myocardial infarction (MI) model and MIRI by precision ligation of the left anterior descending coronary artery (LAD) through micromanipulation is described. Accurate and reproducible ligature positioning of the LAD helps obtain consistent results for heart injury. ST-segment changes can help to identify model accuracy. The serum level of cardiac troponin T (cTnT) is used to assess the myocardial injury, cardiac ultrasound is employed to evaluate the myocardial systolic function, and Evans-Blue/triphenyl tetrazolium chloride staining is used to measure infarct size. In general, this protocol reduces procedure duration, ensures controllable infarct size, and improves mouse survival.

Here we describe a simple and reproducible method that can induce myocardial infarction or myocardial ischemia-reperfusion injury in mice by precision ligation of the left anterior descending coronary artery through micromanipulation.

Induzione di infarto miocardico e danno da ischemia-riperfusione miocardica nei topi

Acute myocardial infarction is a common cardiovascular disease with high mortality. Myocardial reperfusion injury can counteract the beneficial effects of ...

Left Coronary Artery Ligation: A Surgical Murine Model of Myocardial Infarction

Ischemic heart disease and subsequent myocardial infarction (MI) is one of the leading causes of mortality in the United States and around the world. In order to explore the pathophysiological changes after myocardial infarction and design future treatments, research models of MI are required. Permanent ligation of the left coronary artery (LCA) in mice is a popular model to investigate cardiac function and ventricular remodeling post MI. Here we describe a less invasive, reliable, and reproducible surgical murine MI model by permanent ligation of the LCA. Our surgical model comprises of an easily reversible general anesthesia, endotracheal intubation that does not require a tracheotomy, and a thoracotomy. Electrocardiography and troponin measurement should be performed to ensure MI. Echocardiography at day 28 after MI will discern heart function and heart failure parameters. The degree of cardiac fibrosis can be evaluated by Masson's trichrome staining and cardiac MRI. This MI model is useful for studying the pathophysiological and immunological alterations after MI.

Presented here is a surgical procedure for permanent ligation of the left coronary artery in mice. This model can be used to investigate the pathophysiology and associated inflammatory response after myocardial infarction.

Legatura coronaria sinistra: un modello chirurgico murino di infarto miocardico

Ischemic heart disease and subsequent myocardial infarction (MI) is one of the leading causes of mortality in the United States and around the world. In ...

LAD-Legatura: un modello murino di infarto miocardico

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Capitoli in questo video

Infarto acuto del miocardio in topi

Legatura dell'arteria coronarica e di iniezione intramiocardico in un modello murino di infarto

Tecnica modificata di legatura dell'arteria coronarica in Mouse

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

Legatura permanente dell'arteria discendente anteriore sinistra coronarica nei topi: un modello di post-infarto rimodellante miocardico e insufficienza cardiaca

Murino discendente anteriore sinistra (LAD) Coronary legatura dell'arteria: una migliore e semplificata del modello di infarto miocardico

Modello di infarto miocardico Murine utilizzando la legatura permanente dell'arteria coronaria discendente anteriore sinistra

A New Model of Heart Failure Post-Myocardial Infarction in the Rat

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