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	<li>Kloner, R. a., Jennings, R. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Consequences+of+Brief+Ischemia:+Stunning,+Preconditioning,+and+Their+Clinical+Implications:+Part+1.">Consequences of Brief Ischemia: Stunning, Preconditioning, and Their Clinical Implications: Part 1.</a> Circulation. 104 (24), 2981-2989 (2001).</li><li>Mentzer, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Myocardial+protection+in+heart+surgery.">Myocardial protection in heart surgery.</a> J Cardiovasc Pharmacol Ther. 16 (3-4), 290-297 (2011).</li><li>Chambers, D. J., Fallouh, H. 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J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+isolated+perfused+heart+characteristics+and+cautions.">Mouse isolated perfused heart characteristics and cautions.</a> Clin Exp Pharmacol Physiol. 30 (11), 867-878 (2003).</li><li>Miller, A., Wright, G. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fabrication+of+Murine+Ventricular+Balloons+for+the+Langendorff+Heart+Preparation.">Fabrication of Murine Ventricular Balloons for the Langendorff Heart Preparation.</a> J Biotecnol Biomater. 1 (101), 1-4 (2011).</li><li>Curtis, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterisation,+utilisation+and+clinical+relevance+of+isolated+perfused+heart+models+of+ischaemia-induced+ventricular+fibrillation.">Characterisation, utilisation and clinical relevance of isolated perfused heart models of ischaemia-induced ventricular fibrillation.</a> Cardiovasc Res. 39 (1), 194-215 (1998).</li><li>Clements, R. T., Feng, J., Cordeiro, B., Bianchi, C., Sellke, F. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=p38+MAPK-dependent+small+HSP27+and+&#945;B-crystallin+phosphorylation+in+regulation+of+myocardial+function+following+cardioplegic+arrest.">p38 MAPK-dependent small HSP27 and &#945;B-crystallin phosphorylation in regulation of myocardial function following cardioplegic arrest.</a> American journal of physiology. Heart and circulatory physiology. 300 (5), H1669-H1677 (2011).</li><li>Clements, R. T., Cordeiro, B., Feng, J., Bianchi, C., Sellke, F. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rottlerin+increases+cardiac+contractile+performance+and+coronary+perfusion+through+BKCa+++channel+activation+after+cold+cardioplegic+arrest+in+isolated+hearts.">Rottlerin increases cardiac contractile performance and coronary perfusion through BKCa++ channel activation after cold cardioplegic arrest in isolated hearts.</a> Circulation. 124 (11 Suppl), S55-S61 (2011).</li></ol>

The authors have nothing to disclose.

שיטות פרטי פרוטוקול הקודמת להעריך מדהים משנית שריר לב לאיסכמיה הגלובלית הקשורים מעצר cardioplegic. בידיים שלנו פרוטוקול זה מייצר ירידה של 40% בקירוב ~ בתפקוד לב (LVDP, +/- DP / DT) עם שינויים מינימאליים בקצב לב בנקודת הזמן שלאחר reperfusion-30 דק &#39;. כלב reperfused ומחמם מחדש את כל הפרמטרים של ?...

שריר לב מדהים מוגדר כפעילות הפיכה מופחתת התכווצות למרות שיקום של זרימת דם נאותה לאחר תקופה קצרה של איסכמיה או תקופות ממושכות של עלבונות איסכמי עם 1,2,3,4,5 הלבבי. השיטה הוצגה משמשת במיוחד למודל עלבונות איסכמי רלוונטיים קליני אשר יכול לגרום לליקויים הפיכים בתפקוד התכווצות (כלומר, עלבונות איסכמי הקשורים לניתוח לב ניצול מעצר cardioplegic, תקופות קצרות של איסכמיה, תעוקת חזה, וכו &#39;). בניגוד למחקרים חמורים איסכמיה (אוטם שריר לב, נמק) פרוטוקול זה פותח כדי להעריך התאוששות שריר לב פונקציונלית ולבבי ללא פגיעה ברקמות, שיפוץ, ומוות של תאים. רוב הנייר דן פרוטוקול מעצר cardioplegic סטנדרטי עם אלמנטים דומים לניתוח לב באמצעות היפותרמיה ומשלוח cardioplegia לסירוגין. prot שריר לבשיקוף ברוב ניתוחי לב מסתמך על cardioplegia ומעקף לב-ריאה. למרות cardioplegia פתרונות (CP) ואסטרטגיות להשתנות במידה רבה (דם, גְבִישָׁן, וכו &#39;קר, חם) האלמנטים הנפוצים ביותר הם) היפרקלמיה 1 ו / או אסטרטגיות אחרות למעצר הלב בירוויח, וכך להגביל את ניצול אנרגיה כתוצאה מהתכווצות שריר לב, ו -2) היפותרמיה כדי להאט את חילוף החומרים ומסייעות לשמור על ATP ועתודות אנרגיה אחרות בזמן שנעצרה. פתרונות cardioplegia נוכחיים לספק הגנה ללב מפני עלבונות איסכמי שאחרת היה להוכיח קטלני. עם זאת, אסטרטגיות על הלב במהלך עלבונות איסכמי כירורגית אינן מושלמים, ולפציעתם איסכמי קלה כתוצאה עלולה לגרום לבעיות בתפקוד התכווצות לב הפיכה למרות זרימת דם מספקת (שריר לב מדהים), חמצת, נזק cardiomyocyte, והשפעות של כלי דם הכליליים כוללים זלוף המופחת וvasospasm. נבדל פרוטוקול זהממודלי איסכמיה לב מבודדים סטנדרטיים הערכת אוטם שריר לב ואיסכמיה קשה בכך שהוא מעריך עלבונות איסכמי מתונים יותר אשר יכול לגרום לתפקוד לב הלקוי הבא איסכמיה הקצרה או עלבונות איסכמי הקשורים מעצר cardioplegic. (לסקירה על טכניקות זלוף Langendorff ואני / לימודי R לראות 6-8). להנחיות כלליות וניתוח מעמיק של פרמטרים ניסוי קשורים מבודד לב perfused עכבר לראות אל t דואר סאתרלנד. 2,003 9 הטכניקה המוצגת כאן מפרטת את הציוד הדרוש, חומרים כימיים, צעדים, אסטרטגיות וטיפים כדי לגרום באופן מהימן מדהים בלב עכבר. שינויים קלים יש צורך ליישם את הטכנולוגיה על חולדות. בקצרה לבבות עכבר בודד הם Langendorff perfused לכ 30 דקות עם חיץ קרבס-Henseleit פיסיולוגי (KHB), ואחריו דום לב מוגן קר באמצעות משלוח של hypotherm hyperkalemicפתרון cardioplegia IC. בעקבות מעצר, התאוששות תפקודית לב להשגחה במהלך החימום מחדש וreperfusion של הלב עם KHB. שינויים במידת ההתאוששות של תפקוד התכווצות לב ניתן להעריך להעריך סוכנים על הלב ואסטרטגיות לבביות שונות.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr >
			<td >Cardioplegia Solution (St Thomas II)</td>
			<td ></td>
			<td ></td>
			<td >Symbol / Concentrations (mM)</td>
		</tr>
		<tr >
			<td >Sodium Chloride</td>
			<td ></td>
			<td ></td>
			<td>NaCl; 110</td>
		</tr>
		<tr >
			<td >Potassium chloride</td>
			<td ></td>
			<td ></td>
			<td>KCl; 16</td>
		</tr>
		<tr >
			<td >Calcium Chloride</td>
			<td ></td>
			<td ></td>
			<td>CaCL2; 1.5</td>
		</tr>
		<tr >
			<td >Magnesium Chloride</td>
			<td ></td>
			<td ></td>
			<td>MgCL2; 16</td>
		</tr>
		<tr >
			<td >Sodium Bicarbonate</td>
			<td ></td>
			<td ></td>
			<td>NaHCO3; 10</td>
		</tr>
		<tr >
			<td >Krebs-Heinslet Buffer</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Sodium Chloride</td>
			<td ></td>
			<td ></td>
			<td>NaCl; 118</td>
		</tr>
		<tr >
			<td >Potassium Chloride</td>
			<td ></td>
			<td ></td>
			<td>KCl; 4.8</td>
		</tr>
		<tr >
			<td >Magnesium Sulfate</td>
			<td ></td>
			<td ></td>
			<td>MgSO4; 1.7</td>
		</tr>
		<tr >
			<td >Sodium Bicarbonate</td>
			<td ></td>
			<td ></td>
			<td>NaHCO3; 24.9</td>
		</tr>
		<tr >
			<td >Potassium Phosphate (monobasic)</td>
			<td ></td>
			<td ></td>
			<td>KH2PO4; 1.2</td>
		</tr>
		<tr >
			<td >Calcium Chloride</td>
			<td ></td>
			<td ></td>
			<td>CaCL2; 1.4</td>
		</tr>
		<tr >
			<td >Sodium Pyruvate</td>
			<td ></td>
			<td ></td>
			<td>Na pyruvate; 2</td>
		</tr>
		<tr >
			<td >Glucose</td>
			<td ></td>
			<td ></td>
			<td>C6H12O6; 6</td>
		</tr>
		<tr >
			<td >Balloon reagents</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Corn Syrup</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Spaghetti</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Silicon Dispersion Gel</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >styrofoam block</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >lab oven/incubator ( 50C)</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Langendorff Perfusion equipment</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Isolated perfused heart sytem (IH-SR (Hugo-Sachs) or equivalent)</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Data acquisition system (DSI, ADinstruments or equivalent)</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Heated water circulator</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Cooling water circulator</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Perfusion pump capable of 2-30 ml/min</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Inline perfusion filters - 1 um glass fiber</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Pressure sensors and amplifiers for LVP and perfusion pressure</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Small graduated cylinder (~10 mL)</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Small temperature probe and thermometer (Werner or equivalent)</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >perfusion resevoir (1L)</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >cardioplegia resevoir (~200 mL)</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >gas bubbler</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >95/5 O2/CO2 mix</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Surgical tools and reagents</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Metzenbaum and Potz surgical scissors</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >two Dumont size 5 forceps</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >ketamine</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >xylazine</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >heparin</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >small clamp with soft sides to hold aorta (i.e. terminal clamp with taped ends)</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Silk 2-0 and 4-0 sutures</td>
			<td ></td>
			<td ></td>
			<td></td>
		</tr>
	</tbody>
</table>

murine isolated heart model of myocardial stunning associated with cardioplegic arrest

הפרוטוקול הבא הוא שימוש להעריך תפקוד לב לקוי או עלבונות איסכמי מתונים הבאים מדהים שריר לב. הטכניקה שימושית לדוגמנות פגיעת איסכמית קשורה עם תופעה רלוונטית קליני רב, כולל ניתוחי לב עם מעצר cardioplegic ומעקף לב-ריאה, CABG מחוץ למשאבה, השתלה, תעוקת חזה, איסכמיה קצרה, וכו &#39;. הפרוטוקול מציג שיטה כללית למודל מעצר היפותרמיה hyperkalemic cardioplegic וreperfusion בלב מכרסמים המתמקדים במדידה של תפקוד שריר לב התכווצות. בקיצור, לב עכבר perfused במצב Langendorff, instrumented עם בלון תוך חדרי, ופרמטרים תפקודיים לב בתחילת המחקר נרשמים. בעקבות ייצוב, הלב הוא אז נושא לתדרך עירוי של פתרון cardioplegia היפותרמיה על הלב ליזום מעצר הדיאסטולי. Cardioplegia מועבר לסירוגין מעל 2 שעות. הלב אז reperfused וwarmeד לטמפרטורות והתאוששות של תפקוד שריר לב normothermic מנוטר. שימוש בתוצאות פרוטוקול זה בפונקצית התכווצות אמינה מדוכאת לב ללא נזק לרקמות שריר לב ברוטו במכרסמים.

איור 1 מציג תוצאות טיפוסיות מניסוי עכבר אחד. LVP (קו אדום), DP / DT (קו ירוק), וטמפרטורה (קו סגול) נרשמו continusouly על ~ 3 שעות. מכתבים מצביעים - מדידת בסיס, B, C, D, E - משלוח של פתרון cardioplegia, ו - תחילת reperfusion, G, H, I, J - מדידה של זרימת cornary במהלך reperfusion. הערה, LVDP המדוכא וDP / DT על reperfusion ל?...

Watch this Scientific Journal Video about Murine Isolated Heart Model of Myocardial Stunning Associated with Cardioplegic Arrest at JoVE.com

Murine Isolated Heart Model of Myocardial Stunning Associated with Cardioplegic Arrest

The goal of this protocol to assess myocardial stunning following ischemic cardioplegic arrest in rodents.

דגם לב מבודד עכברי של Associated מקסימה שריר הלב עם מעצר Cardioplegic

The following protocol is of use to evaluate impaired cardiac function or myocardial stunning following moderate ischemic insults. The technique is useful ...

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11.6K Views.  Brown University. The goal of this protocol to assess myocardial stunning following ischemic cardioplegic arrest in rodents.

Video: Murine Isolated Heart Model of Myocardial Stunning Associated with Cardioplegic Arrest

A Murine Closed-chest Model of Myocardial Ischemia and Reperfusion

Surgical trauma by thoracotomy in open-chest models of coronary ligation induces an immune response which modifies different mechanisms involved in ischemia and reperfusion. Immune response includes cytokine expression and release or secretion of endogenous ligands of innate immune receptors. Activation of innate immunity can potentially modulate infarct size. We have modified an existing murine closed-chest model using hanging weights which could be useful for studying myocardial pre- and postconditioning and the role of innate immunity in myocardial ischemia and reperfusion. This model allows animals to recover from surgical trauma before onset of myocardial ischemia.
Volatile anesthetics have been intensely studied and their preconditioning effect for the ischemic heart is well known. However, this protective effect precludes its use in open chest models of coronary artery ligation. Thus, another advantage could be the use of the well controllable volatile anesthetics for instrumentation in a chronic closed-chest model, since their preconditioning effect lasts up to 72 hours. Chronic heart diseases with intermittent ischemia and multiple hit models are other possible applications of this model.
For the chronic closed-chest model, intubated and ventilated mice undergo a lateral blunt thoracotomy via the 4th intercostal space. Following identification of the left anterior descending a ligature is passed underneath the vessel and both suture ends are threaded through an occluder. Then, both suture ends are passed through the chest wall, knotted to form a loop and left in the subcutaneous tissue. After chest closure and recovery for 5 days, mice are anesthetized again, chest skin is reopened and hanging weights are hooked up to the loop under ECG control.
At the end of the ischemia/reperfusion protocol, hearts can be stained with TTC for infarct size assessment or undergo perfusion fixation to allow morphometric studies in addition to histology and immunohistochemistry.

Surgical trauma induces an inflammatory response. Cytokines and endogenous ligands are known to modulate myocardial infarct size following ischemia and reperfusion. We present a modified closed-chest model of murine ischemia and reperfusion using hanging weights to minimize effects of thoracotomy.

דגם Murine סגור החזה של איסכמיה של שריר הלב reperfusion

Surgical trauma by thoracotomy in open-chest models of coronary ligation induces an immune response which modifies different mechanisms involved in ...

Murine Model of Wound Healing

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. Impaired wound healing, which occurs in diabetic patients for example, can lead to severe unfavorable outcomes such as amputation. There is, therefore, an increasing impetus to develop novel agents that promote wound repair. The testing of these has been limited to large animal models such as swine, which are often impractical. Mice represent the ideal preclinical model, as they are economical and amenable to genetic manipulation, which allows for mechanistic investigation. However, wound healing in a mouse is fundamentally different to that of humans as it primarily occurs via contraction. Our murine model overcomes this by incorporating a splint around the wound. By splinting the wound, the repair process is then dependent on epithelialization, cellular proliferation and angiogenesis, which closely mirror the biological processes of human wound healing. Whilst requiring consistency and care, this murine model does not involve complicated surgical techniques and allows for the robust testing of promising agents that may, for example, promote angiogenesis or inhibit inflammation. Furthermore, each mouse acts as its own control as two wounds are prepared, enabling the application of both the test compound and the vehicle control on the same animal. In conclusion, we demonstrate a practical, easy-to-learn, and robust model of wound healing, which is comparable to that of humans.

A murine model of cutaneous wound healing that can be used to assess therapeutic compounds in physiological and pathophysiological settings.

מודל עכברי של ריפוי פצע

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. ...

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.

דגם של שריר הלב איסכמיה reperfusion הפגיעה Murine באמצעות קשירת של העורק השמאלי קדמי יורד

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

3D Whole-heart Myocardial Tissue Analysis

Cardiac regenerative therapies aim to protect and repair the injured heart in patients with ischemic heart disease. By injecting stem cells or other biologicals that enhance angio- or vasculogenesis into the infarct border zone (IBZ), tissue perfusion is improved, and the myocardium can be protected from further damage. For maximum therapeutic effect, it is hypothesized that the regenerative substance is best delivered to the IBZ. This requires accurate injections and has led to the development of new injection techniques. To validate these new techniques, we have designed a validation protocol based on myocardial tissue analysis. This protocol includes whole-heart myocardial tissue processing that enables detailed two-dimensional (2D) and three-dimensional (3D) analysis of the cardiac anatomy and intramyocardial injections. In a pig, myocardial infarction was created by a 90-min occlusion of the left anterior descending coronary artery. Four weeks later, a mixture of a hydrogel with superparamagnetic iron oxide particles (SPIOs) and fluorescent beads was injected in the IBZ using a minimally-invasive endocardial approach. 1 h after the injection procedure, the pig was euthanized, and the heart was excised and embedded in agarose (agar). After the solidification of the agar, magnetic resonance imaging (MRI), slicing of the heart, and fluorescence imaging were performed. After image post-processing, 3D analysis was performed to assess the IBZ targeting accuracy. This protocol provides a structured and reproducible method for the assessment of the targeting accuracy of intramyocardial injections into the IBZ. The protocol can be easily used when the processing of scar tissue and/or validation of the injection accuracy of the whole heart is desired.

This protocol describes a novel method for the 3D comparison of whole-heart myocardial tissue with MRI. This is designed for the accurate assessment of intramyocardial injections in the infarct border zone of a chronic porcine model of myocardial infarction.

כל 3D-לב בדיקת רקמות שריר הלב

Cardiac regenerative therapies aim to protect and repair the injured heart in patients with ischemic heart disease. By injecting stem cells or other ...

The Inverted Heart Model for Interstitial Transudate Collection from the Isolated Rat Heart

The present protocol describes a unique approach that enables the collection of cardiac transudate (CT) from the isolated, saline-perfused rat heart. After isolation and retrograde perfusion of the heart according to the Langendorff technique, the heart is inverted into an upside-down position and is mechanically stabilized by a balloon catheter inserted into the left ventricle. Then, a thin latex cap &#8211; previously cast to match the average size of the rat heart &#8211; is placed over the epicardial surface. The outlet of the latex cap is connected to silicon tubing, with the distal opening 10 cm below the base level of the heart, creating slight suction. CT continuously produced on the epicardial surface is collected in ice-cooled vials for further analysis. The rate of CT formation ranged from 17 to 147 &#181;L/min (n = 14) in control and infarcted hearts, which represents 0.1-1% of the coronary venous effluent perfusate. Proteomic analysis and high performance liquid chromatography (HPLC) revealed that the collected CT contains a wide spectrum of proteins and purinergic metabolites.

This protocol describes a method to collect cardiac interstitial fluid from the isolated, perfused rat heart. To physically separate interstitial transudate from coronary venous effluent perfusate, the Langendorff perfused heart is inverted, and the transudate (interstitial fluid) formed on the cardiac surface is collected using a soft latex cap.

מודל הלב הפוכה עבור אוסף transstate Interstitial מן הלב עכברוש מבודד

The present protocol describes a unique approach that enables the collection of cardiac transudate (CT) from the isolated, saline-perfused rat heart. ...

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.

מודל אוטם שריר הלב באמצעות הארכה קבועה של עורק שמאלי קדמי כלילי יורד

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

A Cryoinjury Model to Study Myocardial Infarction in the Mouse

The use of animal models is essential for developing new therapeutic strategies for acute coronary syndrome and its complications. In this article, we demonstrate a murine cryoinjury infarct model that generates precise infarct sizes with high reproducibility and replicability. In brief, after intubation and sternotomy of the animal, the heart is lifted from the thorax. The probe of a handheld liquid nitrogen delivery system is applied onto the myocardial wall to induce cryoinjury. Impaired ventricular function and electrical conduction can be monitored with echocardiography or optical mapping. Transmural myocardial remodeling of the infarcted area is characterized by collagen deposition and loss of cardiomyocytes. Compared to other models (e.g., LAD-ligation), this model utilizes a handheld liquid nitrogen delivery system to generate more uniform infarct sizes.

This article demonstrates a model to study cardiac remodeling after myocardial cryoinjury in mice.

מודל לפציעה בהקפאה לחקור אוטם שריר הלב בעכבר

The use of animal models is essential for developing new therapeutic strategies for acute coronary syndrome and its complications. In this article, we ...

Establishing a Swine Model of Post-myocardial Infarction Heart Failure for Stem Cell Treatment

Although advances have been achieved in the treatment of heart failure (HF) following myocardial infarction (MI), HF following MI remains one of the major causes of mortality and morbidity around the world. Cell-based therapies for cardiac repair and improvement of left ventricular function after MI have attracted considerable attention. Accordingly, the safety and efficacy of these cell transplantations should be tested in a preclinical large animal model of HF prior to clinical use. Pigs are widely used for cardiovascular disease research due to their similarity to humans in terms of heart size and coronary anatomy. Therefore, we sought to present an effective protocol for the establishment of a porcine chronic HF model using closed-chest coronary balloon occlusion of the left circumflex artery (LCX), followed by rapid ventricular pacing induced with pacemaker implantation. Eight weeks later, the stem cells were administered by intramyocardial injection in the peri-infarct area. Then the infarct size, cell survival, and left ventricular function (including echocardiography, hemodynamic parameters, and electrophysiology) were evaluated. This study helps establish a stable preclinical large animal HF model for stem cell treatment.

We sought to establish a swine model of heart failure induced by left circumflex artery blockage and rapid pacing to test the effect and safety of intramyocardial administration of stem cells for cell-based therapies.

הקמת מודל חזירים של אי ספיקת לב לאחר שריר הלב לטיפול בתאי גזע

Although advances have been achieved in the treatment of heart failure (HF) following myocardial infarction (MI), HF following MI remains one of the major ...

Myocardial Infarction by Percutaneous Embolization Coil Deployment in a Swine Model

Myocardial infarction (MI) is the leading cause of mortality worldwide. Despite the use of evidence-based treatments, including coronary revascularization and cardiovascular drugs, a significant proportion of patients develop pathological left-ventricular remodeling and progressive heart failure following MI. Therefore, new therapeutic options, such as cellular and gene therapies, among others, have been developed to repair and regenerate injured myocardium. In this context, animal models of MI are crucial in exploring the safety and efficacy of these experimental therapies before clinical translation. Large animal models such as swine are preferred over smaller ones due to the high similarity of swine and human hearts in terms of coronary artery anatomy, cardiac kinetics, and the post-MI healing process. Here, we aimed to describe an MI model in pig by permanent coil deployment. Briefly, it comprises a percutaneous selective coronary artery cannulation through retrograde femoral access. Following coronary angiography, the coil is deployed at the target branch under fluoroscopic guidance. Finally, complete occlusion is confirmed by repeated coronary angiography. This approach is feasible, highly reproducible, and emulates the pathogenesis of human non-revascularized MI, avoiding the traditional open-chest surgery and the subsequent postoperative inflammation. Depending on the time of follow-up, the technique is suitable for acute, sub-acute, or chronic MI models.

Myocardial infarction (MI) animal models that emulate the natural process of the disease in humans are crucial to understanding pathophysiological mechanisms and testing the safety and efficacy of new emergent therapies. Here, we describe an MI swine model created by deploying a percutaneous embolization coil.

אוטם שריר הלב על ידי פריסת סליל אמבוליזציה מלעורית במודל חזירים

Myocardial infarction (MI) is the leading cause of mortality worldwide. Despite the use of evidence-based treatments, including coronary revascularization ...

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.

קשירת עורקים כליליים שמאליים: מודל מורין כירורגי של אוטם שריר הלב

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 ...