1. Hazırlık 1.1. Sıçan anestezi <ol><li> Sıçan uyuşturmak için izofluran (% 5, yaklaşık 3 dakika odasının boyutuna bağlı olarak) ile doldurulmuş bir bölme içine sıçan yerleştirin. </li><li> Bir kez anestezi, sıçan kaldırmak ve tartılır. </li><li> Anestezi korumak için anestezi maskesi (oksijen 1 L / dk izofluran% 2-3) içine sıçan burun yerleştirin. Izofluran ile anestezi sırasında, farelerin kalp hızı 300-340 bpm (farelerde 380-420 bpm) için azaltın. </li></ol> 1.2. Bir kuyruk ven kanül takın <ol><li> Kan damarlarının daha kolay görülebilir olmasını sağlamak için, sıcak su (38 ° C) ve sabun ile sıçan kuyruk yıkayın. </li><li> Kolayca kuyruk lateral görülebilir ya damar, cannulate. Bir 22-24 G iv kateter kullanarak, girişimleri yaklaşık 1/3 ucundan yol başlar. </li><li> Ilk çabalar başarısız olursa, daha proksimale yeniden deneyin. </li><li> Kan sam alhematokrit analizi (hücre dışı hacim oranı = ECV hesaplamak için gerekli) için ple. </li><li> Cilt yapıştırıcı ve bant ile iv kateter sabitleyin. </li></ol> 1.3. Elektrot Konumlandırma <ol><li> Alkol doymuş çubukla ya da sabun ve su ile ayak pedleri temizleyin. </li><li> Dört elektrot, her ayak için bir ihtiyaç vardır. </li><li> Kapkaççı ortasına elektrotlar takın ve yapışkan bant ile sabitleyin. </li><li> Büküm veya EKG sinyal parazit neden olur döngüler oluşumunu en aza indirmek için birbirlerine etrafında EKG kabloları kıvrım. </li></ol> 2. Tarama 2.1. Hayvan ve izleme Konumlandırma <ol><li> Görüntüleme tüp üzerine sırtüstü ya da yüzükoyun pozisyonda sıçan yerleştirin ve bobinin merkezinde kalp yerleştirin. </li><li> Burnunu (oksijen 1 L / dak 2-3%) izofluran anestezi sunar koni aittir böylece sıçan düzenleyin. Sıçan nefes izin verilirserbestçe tüm görüntüleme işlem boyunca. </li><li> Anal deliği de termometre sensörü yerleştirin ve bant ile masaya sabitleyin. </li><li> Vücut ısısı 38 tutulur ± 1 ° C sıcak su ısıtma sistemi. Isınma mat bobin dışına doğru uzanır, hayvanın alt yüzünde altına yerleştirilir. Daha fazla bilgi için MR deney düzeneği (Şekil 2) şematik bakın. </li><li> EKG elektrotları bağlayın, bir kez EKG sinyali görüntüleme başlar stabildir. </li></ol> 2.2. Tarama protokolü / Görüntüleme parametreleri <ol><li> Bu çalışmada 70 mm iç çapı olan bir selenoid bobin ile bir Philips Ingenia 3.0T klinik MR sistemi [MR sistem gereksinimleri küçük bir delik (örneğin 16 cm) veya özel küçük hayvan ile büyük delik (insan boyutu, örneğin 65 cm) olan kullanıldı bobin, 500/dak, anestezik gazlar için oksijen kaynağı ve bir kaldırma sistemi] için kalp hızı için EKG yolluk yetenekleri kadar. </li><li> Görüş MRG alanının merkezinde kalp bulmak için bir anket ile başlayın. </li><li> Konumu doğru bir kez, kısa eksen görüntülerin yığının geometri belirlemek için iki odalı ve dört odacıklı manyetik rezonans görüntüleme manzaralı devam ediyor. </li><li> Iki ve dört boşluk görüntüleri (PreSALLI) üzerine SALLI için, konum orta boşluğu kısa eksen dilim. 4000 msn satın alma süresi ve 4000 msn dinlenme süresi kombinasyonu z ekseni boyunca manyetizasyon yeterli iyileşme sağlar ve eğimleri aşırı ısınmasını engeller. Fonksiyonel analiz etkinleştirmek için, aşamaları satın hızlandırmak için faktör 2 zamansal Undersampling ile, en az 12 olarak ayarlanmalıdır. </li><li> Sıçan hareket ettirmeden, kalıcı kateter içine gadolinyum tabanlı kontrast madde enjekte edilir. Beş dakika bekleyin. </li><li> En az 7 dilim (kesit kalınlığı 2.4 mm) oluşan, çok kesitli kısa eksen yığını olarak SALLI planlama başlar. En distal altında kalp ve t tepe olduğunu dilimleri yerleştirino üst düzey kalp vanaları hemen distalinde olduğunu. Kısa eksen septum dik olduğundan emin olmak için deneyin. Hemen hemen her 30 dakikada bir (üç Sallis civarında) kontrast madde bir doz enjekte edilir. </li><li> Görüntü elde etme işlemi tamamlandığında tarayıcıdan sıçan çıkarın ve anestezi kurtarmak için izin verir. </li></ol> 3. Görüntü Oluşturma Resim yeniden özel bir görüntü oluşturma seçeneğini kullanarak, önceden tanımlanmış yeniden parametreleri, veya çevrimdışı kullanarak ya online yapılabilir: 3.1. Çevrimiçi İmar <ol><li> Çeşitli parametreler de dahil olmak üzere tanımlanabilir: </li></ol><ul><li> Kalp döngüsü içindeki konumu ve yeniden pencerenin genişliği (örneğin msn 50 ila 100 den kalp hızı 300/min de sistolik T1 haritası elde etmek için): T1 haritalama </li><li> IR hazırlanmış (LGE) görüntüler için: ters zaman konumu ve genişliği (TI) görüntü pencere ve sayısı yeniden wi olmakince bu pencere (örneğin TI 100-300 msn, 5 görüntüleri, tis 100-150-200-250-300 msn 5 LGE görüntüler oluşturmak için). </li></ul> 3.2. Çevrimdışı İmar <ol><li> Görüntü oluşturma için özel bir yazılım paketi (Gyrotools, Zürih, İsviçre) kullanırken, daha interaktif bir şekilde üç grup veri (sine MR, inversiyon kurtarma ve T1 haritalar) ayıklayın. </li><li> Ilgili sine görüntü seçerek T1 için son sistol veya son diyastol tanımı ayarlayın. </li><li> Renkli haritalar gibi T1 haritalar gözünüzde canlandırın. Ilgi alanı üzerinde fare geçerek kesin değerleri bulun. Görüntüler daha fazla analiz (öncesi ve sonrası kontrast miyokard T1 değerleri ve kan havuzundan ECV örneğin hesaplama) 12 resim biçimlerini saklanabilir. </li></ol>

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N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+the+distribution+volume+of+gadopentetate+dimeglumine+at+echo-planar+MR+imaging+to+quantify+myocardial+infarction:+comparison+with+99mTc-DTPA+autoradiography+in+rats.">Measurement of the distribution volume of gadopentetate dimeglumine at echo-planar MR imaging to quantify myocardial infarction: comparison with 99mTc-DTPA autoradiography in rats.</a> Radiology. 211 (3), 698-708 (1999).</li><li>Messroghli, D. R., Walters, K., Plein, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Myocardial+T1+mapping:+application+to+patients+with+acute+and+chronic+myocardial+infarction.">Myocardial T1 mapping: application to patients with acute and chronic myocardial infarction.</a> Magn. Reson. Med. 58 (1), 34-40 (2007).</li><li>O H-Ici, D., Ridgway, J., Kuehne, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiovascular+magnetic+resonance+of+myocardial+edema+using+a+short+inversion+time+inversion+recovery+(STIR)+black-blood+technique:+Diagnostic+accuracy+of+visual+and+semi-quantitative.">Cardiovascular magnetic resonance of myocardial edema using a short inversion time inversion recovery (STIR) black-blood technique: Diagnostic accuracy of visual and semi-quantitative.</a> 14 (1), (2012).</li><li>Sagar, S., Liu, P. P., Cooper, L. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Myocarditis.">Myocarditis.</a> Lancet. 379, 738-747 (2012).</li><li>Skouri, H. N., Dec, G. W., Friedrich, M. G., Cooper, L. 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G., Sechtem, U., Schulz-Menger, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiovascular+magnetic+resonance+in+myocarditis:+a+JACC+White+Paper.">Cardiovascular magnetic resonance in myocarditis: a JACC White Paper.</a> J. Am. Coll. Cardiol. 54, 1475-1487 (2009).</li><li>Korkusuz, H., Esters, P., Naguib, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acute+myocarditis+in+a+rat+model:+late+gadolinium+enhancement+with+histopathological+correlation.">Acute myocarditis in a rat model: late gadolinium enhancement with histopathological correlation.</a> Eur. Radiol. 19 (11), 2672-2678 (2009).</li><li>Ugander, M., Oki, A. J., Hsu, L. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extracellular+volume+imaging+by+magnetic+resonance+imaging+provides+insights+into+overt+and+sub-clinical+myocardial+pathology.">Extracellular volume imaging by magnetic resonance imaging provides insights into overt and sub-clinical myocardial pathology.</a> Eur. Heart J. 33 (10), 1268-1278 (2012).</li><li>Gilson, W. D., Kraitchman, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+magnetic+resonance+imaging+in+small+rodents+using+clinical+1.5.">Cardiac magnetic resonance imaging in small rodents using clinical 1.5.</a> T and. 3 (1), 35-45 (2007).</li><li>Messroghli, D. R., Radjenovic, A., Kozerke, S., Higgins, D. M., Sivananthan, M. U., Ridgway, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modified+Look-Locker+inversion+recovery+(MOLLI)+for+high-resolution+T1+mapping+of+the+heart.">Modified Look-Locker inversion recovery (MOLLI) for high-resolution T1 mapping of the heart.</a> Magnetic resonance in medicine. 52 (1), 141-146 (2004).</li></ol>

Tüm hayvan prosedürleri Laboratuvar Hayvanları Bakım ve Kullanım Kuralları çerçevesinde yapılan, ve yerel hayvan bakımı yetkililer tarafından onaylanmıştır. Çıkar çatışması ilan etti.

Burada küçük hayvanlarda çok yöntem (sine MR, inversiyon-kurtarma ve T1 haritalar) MR görüntüleri oluşturmak için bir yöntem mevcut. Küçük hayvan araştırma kardiyovasküler hastalık araştırma giderek daha önemli bir rol oynar ve CMR bize miyokard fonksiyonu, yapı ve doku kompozisyon çalışmak için izin güçlü bir araçtır. Ancak, küçük hayvan CMR yüksek kalp hızı ve küçük kalp boyutu sayesinde benzersiz zorluklar bir numarası vardır. Daha fazla zaman etkin yöntemler de dahil olmak ...

Miyokardit akut kalp yetmezliği, ani ölüm ve kronik dilate kardiyomiyopati 7 önemli bir nedenidir. CMR fonksiyon ölçümü için ve in vivo doku analizi için altın standart yöntem olarak kurulmuştur. Roman görüntüleme teknikleri ve görüntüleme iyileştirmeler sadece miyokardit tanısı geliştirmek, aynı zamanda patofizyolojisi ve tedavi hedefleri 8-10 hızı belirlenmesi çalışma yardımcı olamazdı. Küçük hayvan görüntüleme kalp ve damar hastalıkları çalışma için önemli bir araçtır. Bu geç gadolinyum geliştirme (LGE) olarak rutin klinik CMR kullanılan teknikleri, kolayca hayvanların yüksek kalp hızı nedeniyle küçük hayvan CMR transfer edilemez, ancak zaten 11 gösterilebilir. Yaklaşım çok modlu görüntü verilerini oluşturur küçük hayvan Look-Locker inversiyon kurtarma (SALLI) kalp fonksiyonu ve morfolojisi hem de kapsamlı bir değerlendirme (Şekil 1 için izin ayarlarnd 3). Burada ayrıntı, prosedür ve tipik SALLI protokol ile küçük hayvan görüntüleme için kurulum, göstermektedir. Özellikle biz T1 görüntüleme veri setleri yeniden inşası ve analiz göstermektedir.

<table border="1">
		<tbody>
		 <tr>
			<td>Name of Reagent/Material</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		 </tr>
		 <tr>
			<td>Adhesive Tape (Silkafix)</td>
			<td>Lohmann und Rauscher</td>
			<td>34327</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Gadopentetat-Dimeglumin (Magnevist)</td>
			<td>Bayer</td>
			<td>G-00012163</td>
			<td>2mmol/Kg</td>
		 </tr>
		 <tr>
			<td>Introcan Safety-W (G24)</td>
			<td>B. Braun</td>
			<td>4254503-01</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Red Dot, Neonatal Monitoring Electrode with Pre-Attached Lead Wire</td>
			<td>3M</td>
			<td>2269T</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Skin glue (Histoacryl)</td>
			<td>B. Braun</td>
			<td>1050052</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Scales (Typ 440)</td>
			<td>Kern</td>
			<td>95088</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Skin desinfection (Softasept N)</td>
			<td>B. Braun Petzold</td>
			<td>360250</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Thermometer </td>
			<td>LumaSense Technologies</td>
			<td>Luxtron 812</td>
			<td></td>
		 </tr>
		</tbody>
 </table>

assessment of cardiac function and myocardial morphology using small animal look-locker inversion recovery (salli) mri in rats

Küçük hayvan manyetik rezonans görüntüleme kalp fonksiyonu ve miyokard doku değişiklikleri incelemek için önemli bir araçtır. Küçük hayvanlar (200 ila 600 atım / dk) yüksek kalp hızı daha önce CMR görüntüleme rolü sınırlıdır. Küçük hayvan Bak-Locker inversiyon kurtarma (SALLI) bu sorunun 1 üstesinden gelmek için küçük hayvanlar için bir T1 haritalama dizisidir. T1 haritalar doku değişiklikleri ve kontrast madde kinetik hakkında nicel bilgi sağlar. Bu tür interstisyel fibrosis veya ödem 1-6 gibi yaygın miyokard işlemleri tespit etmek de mümkündür. Ayrıca, görüntü verilerini tek bir dizi, kalp fonksiyonu ve sine ve inversiyon kurtarma hazırlanmış geç gadolinyum geliştirme tipi MR görüntüleri 1 üreterek yara miyokard incelemek mümkündür. Sunulan video prosedürleri küçük hayvan CMR görüntüleme gerçekleştirmek için adım adım gösterir. Burada Sprague-Dawl sağlıklı bir ile sunulmaktadırey sıçan, ancak doğal olarak farklı kalp küçük hayvan modelleri için uzatılabilir.

Burada sağlıklı bir Sprague Dawley Rat elde edilen bulgular göstermektedir. Daha önce açıklanan bir iyi hazırlanmış hayvan kurulum ile, istikrarlı bir EKG sinyal almak mümkündür. Insan kardiyak MR protokolleri benzer, biz kalp bulmak için bir anket ile başlar. Bobin sıçan yerini doğru ise, biz SALLI yığını için geometri tespit etmek için iki oda görünümü ve dört odacık görüntüsü ile devam edin. SALLI teknik aynı zamanda elde edilen görüntü üç tür ür...

Watch this Scientific Journal Video about Assessment of Cardiac Function and Myocardial Morphology Using Small Animal Look-locker Inversion Recovery SALLI MRI in Rats at JoVE.com

Assessment of Cardiac Function and Myocardial Morphology Using Small Animal Look-locker Inversion Recovery SALLI MRI in Rats

Kontrastlı kardiyak manyetik rezonans (CMR) görüntüleme kapsamlı sağlar<em&gt; In vivo</em&gt; Kardiyovasküler hastalık küçük hayvan modellerinde kalbin değerlendirilmesi. Burada ayrıntılı prosedürleri CMR görüntüleme, yeniden yapılanma ve sıçanlarda Küçük Hayvan Kilit-Locker Ters Kurtarma (SALLI) kullanarak analiz yapmak için.

Küçük Hayvan Bak-soyunma Ters Kurtarma (SALLI) Sıçanlarda MRI kullanarak Kalp Fonksiyonu ve Miyokard Morfoloji Değerlendirilmesi

Small animal magnetic resonance  imaging is an important tool to study cardiac function and changes in myocardial  tissue. The high heart rates of small ...

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Research

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Medicine

Assessment of Cardiac Function and Myocardial Morphology Using Small Animal Look-locker Inversion Recovery (SALLI) MRI in Rats

12.7K Görüntüleme.  German Heart Institute Berlin. Kontrastlı kardiyak manyetik rezonans (CMR) görüntüleme kapsamlı sağlar In vivo Kardiyovasküler hastalık küçük hayvan modellerinde kalbin değerlendirilmesi. Burada ayrıntılı prosedürleri CMR görüntüleme, yeniden yapılanma ve sıçanlarda Küçük Hayvan Kilit-Locker Ters Kurtarma (SALLI) kullanarak analiz yapmak için.

Video: Assessment of Cardiac Function and Myocardial Morphology Using Small Animal Look-locker Inversion Recovery SALLI MRI in Rats

Assessment of Cardiac Function and Energetics in Isolated Mouse Hearts Using 31P NMR Spectroscopy

Bioengineered mouse models have become powerful research tools in determining causal relationships between molecular alterations and models of cardiovascular disease. Although molecular biology is necessary in identifying key changes in the signaling pathway, it is not a surrogate for functional significance. While physiology can provide answers to the question of function, combining physiology with biochemical assessment of metabolites in the intact, beating heart allows for a complete picture of cardiac function and energetics. For years, our laboratory has utilized isolated heart perfusions combined with nuclear magnetic resonance (NMR) spectroscopy to accomplish this task. Left ventricular function is assessed by Langendorff-mode isolated heart perfusions while cardiac energetics is measured by performing 31P magnetic resonance spectroscopy of the perfused hearts. With these techniques, indices of cardiac function in combination with levels of phosphocreatine and ATP can be measured simultaneously in beating hearts. Furthermore, these parameters can be monitored while physiologic or pathologic stressors are instituted. For example, ischemia/reperfusion or high workload challenge protocols can be adopted. The use of aortic banding or other models of cardiac pathology are apt as well. Regardless of the variants within the protocol, the functional and energetic significance of molecular modifications of transgenic mouse models can be adequately described, leading to new insights into the associated enzymatic and metabolic pathways. Therefore, 31P NMR spectroscopy in the isolated perfused heart is a valuable research technique in animal models of cardiovascular disease.

Assessment of Cardiac Function and Energetics in Isolated Mouse Hearts Using 31P NMR Spectroscopy

Langendorff-mode isolated heart perfusion, in conjunction with 31P NMR spectroscopy, combines the fields of biochemistry and physiology into one experiment. The protocol allows for the dynamic measurement of high energy phosphate content and turnover in the heart while concurrently monitoring physiologic function. When performed correctly, this is a valuable technique in the assessment of cardiac energetics.

Kalp Fonksiyonu ve Enerji Kullanımı İzole Fare Kalpler Değerlendirilmesi 31 P NMR Spektroskopisi

Bioengineered mouse models have become powerful research tools in determining causal relationships between molecular alterations and models of ...

Tıp

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.

Sıçanlarda Akut Miyokard Enfarktüsü

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

Protocol for Long Duration Whole Body Hyperthermia in Mice

Hyperthermia is a general term used to define the increase in core body temperature above normal. It is often used to describe the increased core body temperature that is observed during fever. The use of hyperthermia as an adjuvant has emerged as a promising procedure for tumor regression in the field of cancer biology. For this purpose, the most important requirement is to have reliable and uniform heating protocols. We have developed a protocol for hyperthermia (whole body) in mice. In this protocol, animals are exposed to cycles of hyperthermia for 90 min followed by a rest period of 15 min. During this period mice have easy access to food and water. High body temperature spikes in the mice during first few hyperthermia exposure cycles are prevented by immobilizing the animal. Additionally, normal saline is administered in first few cycles to minimize the effects of dehydration. This protocol can simulate fever like conditions in mice up to 12-24 hr. We have used 8-12 weeks old BALB/Cj female mice to demonstrate the protocol.

This paper describes a protocol for whole body hyperthermia in mice that can stimulate fever like conditions up to 12-24 hr.

Farelerde Uzun Süre Whole Body Hipertermi için protokol

Hyperthermia is a general term used to define the increase in core body temperature above normal. It is often used to describe the increased core body ...

MRI and PET in Mouse Models of Myocardial Infarction

Myocardial infarction is one of the leading causes of death in the Western world. The similarity of the mouse heart to the human heart has made it an ideal model for testing novel therapeutic strategies.
In vivo magnetic resonance imaging (MRI) gives excellent views of the heart noninvasively with clear anatomical detail, which can be used for accurate functional assessment. Contrast agents can provide basic measures of tissue viability but these are nonspecific. Positron emission tomography (PET) is a complementary technique that is highly specific for molecular imaging, but lacks the anatomical detail of MRI. Used together, these techniques offer a sensitive, specific and quantitative tool for the assessment of the heart in disease and recovery following treatment.
In this paper we explain how these methods are carried out in mouse models of acute myocardial infarction. The procedures described here were designed for the assessment of putative protective drug treatments. We used MRI to measure systolic function and infarct size with late gadolinium enhancement, and PET with fluorodeoxyglucose (FDG) to assess metabolic function in the infarcted region. The paper focuses on practical aspects such as slice planning, accurate gating, drug delivery, segmentation of images, and multimodal coregistration. The methods presented here achieve good repeatability and accuracy maintaining a high throughput.

We describe how to perform MRI and PET imaging of the mouse heart. The protocol is tailored to assess treatment efficacy in models of myocardial infarction and heart failure.

Myocardial infarction is one of the leading causes of death in the Western world. The similarity of the mouse heart to the human heart has made it an ...

Ascending Aortic Constriction in Rats for Creation of Pressure Overload Cardiac Hypertrophy Model

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart failure. Here, we describe a detailed surgical procedure for creating pressure overload and cardiac hypertrophy in rats by constriction of the ascending aorta using a small metallic clip. After anesthesia, the trachea is intubated by inserting a cannula through a half way incision made between two cartilage rings of trachea. Then a skin incision is made at the level of the second intercostal space on the left chest wall and muscle layers are cleared to locate the ascending portion of aorta. The ascending aorta is constricted to 50&#8211;60% of its original diameter by application of a small sized titanium clip. Following aortic constriction, the second and third ribs are approximated with prolene sutures. The tracheal cannula is removed once spontaneous breathing was re-established. The animal is allowed to recover on the heating pad by gradually lowering anesthesia. The intensity of pressure overload created by constriction of the ascending aorta is determined by recording the pressure gradient using trans-thoracic two dimensional Doppler-echocardiography. Overall this protocol is useful to study the remodeling events and contractile properties of the heart during the gradual onset and progression from compensated cardiac hypertrophy to heart failure stage.

We describe a stepwise procedure for creating pressure overload and left ventricular hypertrophy in Wistar rats by constriction of the ascending aorta using a small metallic clip. This model is extensively used for studying remodeling changes during cardiac hypertrophy and for identifying and evaluating strategies for regression of such changes.

Basınç Aşırı Kardiyak hipertrofi Modeli Oluşturma Ratlarda Aort daralma, Artan

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart ...

Assessment of Right Ventricular Structure and Function in Mouse Model of Pulmonary Artery Constriction by Transthoracic Echocardiography

Emerging clinical data support the notion that RV dysfunction is critical to the pathogenesis of cardiovascular disease and heart failure1-3. Moreover, the RV is significantly affected in pulmonary diseases such as pulmonary artery hypertension (PAH). In addition, the RV is remarkably sensitive to cardiac pathologies, including left ventricular (LV) dysfunction, valvular disease or RV infarction4. To understand the role of RV in the pathogenesis of cardiac diseases, a reliable and noninvasive method to access the RV structurally and functionally is essential.
A noninvasive trans-thoracic echocardiography (TTE) based methodology was established and validated for monitoring dynamic changes in RV structure and function in adult mice. To impose RV stress, we employed a surgical model of pulmonary artery constriction (PAC) and measured the RV response over a 7-day period using a high-frequency ultrasound microimaging system. Sham operated mice were used as controls. Images were acquired in lightly anesthetized mice at baseline (before surgery), day 0 (immediately post-surgery), day 3, and day 7 (post-surgery). Data was analyzed offline using software.
Several acoustic windows (B, M, and Color Doppler modes), which can be consistently obtained in mice, allowed for reliable and reproducible measurement of RV structure (including RV wall thickness, end-diastolic&#160;and end-systolic dimensions), and function (fractional area change, fractional shortening, PA peak velocity, and peak pressure gradient) in normal mice and following PAC.
Using this method, the pressure-gradient resulting from PAC was accurately measured in real-time using Color Doppler mode and was comparable to direct pressure measurements performed with a Millar high-fidelity microtip catheter. Taken together, these data demonstrate that RV measurements obtained from various complimentary views using echocardiography are reliable, reproducible and can provide insights regarding RV structure and function. This method will enable a better understanding of the role of RV cardiac dysfunction.

Right ventricle (RV) dysfunction is critical to the pathogenesis of cardiovascular disease, yet limited methodologies are available for its evaluation. Recent advances in ultrasound imaging provide a noninvasive and accurate option for longitudinal RV study. Herein, we detail a step-by-step echocardiographic method using a murine model of RV pressure overload.

Transtorasik Ekokardiyografi ile Pulmoner Arter Konstrüksiyon Fare Modeli sağ ventrikül yapı ve fonksiyonlarının değerlendirilmesi

Emerging clinical data support the notion that RV dysfunction is critical to the pathogenesis of cardiovascular disease and heart failure1-3. Moreover, ...

Echocardiographic and Histological Examination of Cardiac Morphology in the Mouse

An increasing number of genetically modified mouse models has become available in recent years. Moreover, the number of pharmacological studies performed in mice is high. Phenotypic characterization of these mouse models also requires the examination of cardiac function and morphology. Echocardiography and magnetic resonance imaging (MRI) are commonly used approaches to characterize cardiac function and morphology in mice. Echocardiographic and MRI equipment specialized for use in small rodents is&#160;expensive and requires a dedicated space. This protocol describes cardiac measurements in mice using a clinical echocardiographic system with a 15 MHz human vascular probe. Measurements are performed on anesthetized adult mice. At least three image sequences are recorded and analyzed for each animal in M-mode in the parasternal short-axis view. Afterwards, cardiac histological examination is performed, and cardiomyocyte diameters are determined on hematoxylin-eosin- or wheat germ agglutinin (WGA)-stained paraffin sections. Vessel density is determined morphometrically after Pecam-1 immunostaining. The protocol has been applied successfully to pharmacological studies and different genetic animal models under baseline conditions, as well as after experimental myocardial infarction by the permanent ligation of the left anterior descending coronary artery (LAD). In our experience, echocardiographic investigation is limited to anesthetized animals and is feasible in adult mice weighing at least 25 g.

Echocardiographic examination is frequently used in mice. Expensive high-resolution ultrasound devices have been developed for this purpose. This protocol describes an affordable echocardiographic procedure combined with histological morphometric analyses to determine cardiac morphology.

Kardiyak Morfoloji Ekokardiyografik ve histolojik muayene fare

An increasing number of genetically modified mouse models has become available in recent years. Moreover, the number of pharmacological studies performed ...

In Vivo Evaluation of Fracture Callus Development During Bone Healing in Mice Using an MRI-compatible Osteosynthesis Device for the Mouse Femur

Endochondral fracture healing is a complex process involving the development of fibrous, cartilaginous, and osseous tissue in the fracture callus. The amount of the different tissues in the callus provides important information on the fracture healing progress. Available in vivo techniques to longitudinally monitor the callus tissue development in preclinical fracture-healing studies using small animals include digital radiography and &#181;CT imaging. However, both techniques are only able to distinguish between mineralized and non-mineralized tissue. Consequently, it is impossible to discriminate cartilage from fibrous tissue. In contrast, magnetic resonance imaging (MRI) visualizes anatomical structures based on their water content and might therefore be able to noninvasively identify soft tissue and cartilage in the fracture callus. Here, we report the use of an MRI-compatible external fixator for the mouse femur to allow MRI scans during bone regeneration in mice. The experiments demonstrated that the fixator and a custom-made mounting device allow repetitive MRI scans, thus enabling longitudinal analysis of fracture-callus tissue development.

In Vivo Evaluation of Fracture Callus Development During Bone Healing in Mice Using an MRI-compatible Osteosynthesis Device for the Mouse Femur

The evaluation of tissue development in the fracture callus during endochondral bone healing is essential to monitor the healing process. Here, we report the use of a magnetic resonance imaging (MRI)-compatible external fixator for the mouse femur to allow MRI scans during bone regeneration in mice.

Vivo Fare uyluk için bir MRI uyumlu Osteosentez aygıtı kullanma farelerde kemik iyileşme sırasında kırık Kallus gelişimi değerlendirme

Endochondral fracture healing is a complex process involving the development of fibrous, cartilaginous, and osseous tissue in the fracture callus. The ...

Normothermic Ex Situ Heart Perfusion in Working Mode: Assessment of Cardiac Function and Metabolism

The current standard method for organ preservation (cold storage, CS), exposes the heart to a period of cold ischemia that limits the safe preservation time and increases the risk of adverse post-transplantation outcomes. Moreover, the static nature of CS does not allow for organ evaluation or intervention during the preservation interval. Normothermic ex situ heart perfusion (ESHP) is a novel method for preservation of the donated heart that minimizes cold ischemia by providing oxygenated, nutrient-rich perfusate to the heart. ESHP has been shown to be non-inferior to CS in the preservation of standard-criteria donor hearts and has also facilitated the clinical transplantation of the hearts donated after the circulatory determination of death. Currently, the only available clinical ESHP device perfuses the heart in an unloaded, non-working state, limiting assessments of myocardial performance. Conversely, ESHP in working mode provides the opportunity for comprehensive evaluation of cardiac performance by assessment of functional and metabolic parameters under physiologic conditions. Moreover, earlier experimental studies have suggested that ESHP in working mode may result in improved functional preservation. Here, we describe the protocol for ex situ perfusion of the heart in a large mammal (porcine) model, which is reproducible for different animal models and heart sizes. The software program in this ESHP apparatus allows for real-time and automated control of the pump speed to maintain desired aortic and left atrial pressure and evaluates a variety of functional and electrophysiological parameters with minimal need for supervision/manipulation.

Normothermic ex situ heart perfusion (ESHP), preserves the heart in a beating, semi-physiologic state. When performed in a working mode, ESHP provides the opportunity to perform sophisticated assessments of donor heart function and organ viability. Here, we describe our method for myocardial performance evaluation during ESHP.

Normothermic Ex Situ kalp perfüzyon çalışma modu: değerlendirme kardiyak fonksiyon ve metabolizma

The current standard method for organ preservation (cold storage, CS), exposes the heart to a period of cold ischemia that limits the safe preservation ...

Continuous Blood Sampling in Small Animal Positron Emission Tomography/Computed Tomography Enables the Measurement of the Arterial Input Function

For quantitative analysis and bio-kinetic modeling of positron emission tomography/computed tomography (PET/CT) data, the determination of the temporal blood time-activity concentration also known as arterial input function (AIF) is a key point, especially for the characterization of animal disease models and the introduction of newly developed radiotracers. The knowledge of radiotracer availability in the blood helps to interpret PET/CT-derived data of tissue activity. For this purpose, online blood sampling during the PET/CT imaging is advisable to measure the AIF. In contrast to manual blood sampling and image-derived approaches, continuous online blood sampling has several advantages. Besides the minimized blood loss, there is an improved resolution and a superior accuracy for the blood activity measurement. However, the major drawback of online blood sampling is the costly and time-consuming preparation to catheterize the femoral vessels of the animal. Here, we describe an easy and complete workflow for catheterization and continuous blood sampling during small animal PET/CT imaging and compared it to manual blood sampling and an image-derived approach. Using this highly-standardized workflow, the determination of the fluorodeoxyglucose ([18F]FDG) AIF is demonstrated. Further, this procedure can be applied to any radiotracer in combination with different animal models to create fundamental knowledge of tracer kinetic and model characteristics. This allows a more precise evaluation of the behavior of pharmaceuticals, both for diagnostic and therapeutic approaches in the preclinical research of oncological, neurodegenerative and myocardial diseases.

Here a protocol for continuous blood sampling during PET/CT imaging of rats to measure the arterial input function (AIF) is described. The catheterization, the calibration and setup of the system and the data analysis of the blood radioactivity are demonstrated. The generated data provide input parameters for subsequent bio-kinetic modeling.

Küçük hayvan Pozitron Emisyon Tomografi/Bilgisayarlı tomografi sürekli kan örnekleme arteriyel giriş fonksiyon ölçümü sağlar

For quantitative analysis and bio-kinetic modeling of positron emission tomography/computed tomography (PET/CT) data, the determination of the temporal ...