Bu çalışma, Amerikan Kalp Derneği 14FTF20370058 (DMA) ve NIH T32 HL007101-35 (DMA) tarafından desteklenmektedir.

1. iletkenlik Kateter Hazırlıklar ve Basınç Kalibrasyon <ol><li> Hemodinamik kateter modülüne iletkenlik kateteri bağlayın. Elektronik kateter modülünde ayarlanmış önceden ayarlanmış basınç ve hacim kaydederek basınç ve hacim ölçümlerini kalibre. 0 mm Hg ve 25 mm Hg (Şekil 1A) bir izleme kaydedin ve her iki basınç trasların (Şekil 1B ve 1C) ile gerilimleri atayın. Benzer şekilde, 5 RVU ve 25 RVU (Şekil 1D) bir hacim izleme kayıt ve hem hacim trasların (1E ve 1F) ile gerilimleri atayın. </li><li> Bir cıva sütunu sfingomanometre kullanarak, manuel basınç kalibrasyon ile elektronik basınç kalibrasyonunu onaylayın. 3-yollu ile tansiyon aleti manşet noktasını yerleştirin. Yan bağlantı noktasını kullanarak RT su ile sık sık koroner anjiyoplasti için kullanılan bir 3-port hemostaz valf sistemi, doldurun. <ol><li> Sıvı dolu hemostaz valfi içine iletkenlik kateterin ucunu yerleştirin ve yavaşça zekâ güvenceyehout kateter dolanması. Tansiyon aleti ile hemostaz valfini bağlayın ve 200 mmHg şişirmek ve 3-yollu stopcock kilitleyin. Ölçülen basınç tansiyon aleti üzerinde şişirilmiş basınç uygun olup olmadığını inceler. </li></ol></li><li> Tuzlu su içinde yer kateter çalışma alanı ve ölçü basınç seviyesinde 37 ° C&#39;ye ısıtıldı. Kaydedilen basınçlar sıfır oluncaya kadar basınç kontrolünü ayarlayın. </li></ol> 2. Anestezi / Entübasyon <ol><li> Ketamin / ksilazin bir intraperitoneal olarak (-1 80-100 / 10 mg kg) yönetin. Not: Alternatif anestezik maddeler kullanılabilir. Anestezik kapsamlı bir liste bu tekniğin 11,12 önceki incelemelerde verilmektedir. Uygun Anesthetization nazik kuyruk tutam tarafından teyit edilebilir. </li><li> Bir kez anestezi, ısıtmalı pad üzerinde saç kesme ve yer ile boyun ve göğüs tıraş. 36,5-37,5 ºC fare rektal ısısını korumak. Düşük vücut sıcaklıklarıdepresif kalp hızı neden olacaktır. Kuruluğunu önlemek için gözlere merhem sürün </li><li> Boyundaki bir orta hat kesi yapmak ve trakea maruz uzakta trakea kasları teşrih. Entübasyon sağlamak için trakea görselleştirilmesi ise, ağız yoluyla bir endotrakeal tüpü yerleştirin ve solunum bağlanın. </li><li> İşlem sırasında ventilatör üzerinde fare koruyun. Daha önce açıklandığı gibi 11 ayarla ventilatör ayarları hayvan ağırlığına dayalı. Tidal Hacim (ml) 6.2 x (kilogram hayvan ağırlığı) 1.01 ve Solunum hızı = 53.5 x (kilogram hayvan ağırlığı) -0,26 =. </li></ol> LV odasında İletkenlik Kateterin 3. Yerleştirme <ol><li> Karotis yaklaşımı <ol><li> Sterilite sağlamak için, steril cerrahi aletlerin iki takım ilk cilt kesi ve torakotomi faaliyet biri için used- biridir. Araçlar tek bir cerrahi seans a sırasında hayvanlar arasında kuru sterilizatör kullanılarak dekontamine edilmelidirnd her cerrahi günün sonunda otoklavlanmıştır. </li><li> Cilt Klorheksidin + alkol cilt fırçalayın (% 0.5 klorheksidin /% 70 alkol solüsyonu) üç döngü ile dekontamine edildikten sonra, sternum mandibulanın sağ karotis üzerinde bir kesi yapmak. Sağ karotis maruz doku çevresindeki teşrih ve karotis bitişik çalışan vagus siniri kesti. </li><li> Kravat ve güvenli (uzakta göğüs) karotid arter distal ucuna etrafında steril 6-0 ipek sütür yerleştirin. Gevşek, orta dikiş bağlama, ilk sütür (göğüs yakın) karotis proksimal altında iki ek sütür yerleştirin. Yavaşça proksimal sütür çekin ve cilde sıkma yoluyla emniyete alın. Karotis arter Devam etmeden önce hem proksimal ve distalde kenetlenmiş edilmiş olduğundan emin olun. </li><li> İlk sütür küçük R. karotid arter kesi, proksimal olun ve göğse doğru uzunlamasına uzanır. </li><li> Iletkenlik kateter ucu takın,Daha önce kesikten damar içine, 30 dakika boyunca ılık tuzlu su içinde ıslatılmış ve orta dikiş kullanılarak deriye tespit. </li><li> Doğru yerleşimi sağlamak için izleme basınç-hacim döngü izlerken yavaşça, karotis yoluyla sol ventriküle kateter ilerlemek. Not: dikdörtgen görünür basınç-volüm döngüler verim gerekir kateterin Optimal yerleştirme (Bakınız Şekil 2). Kateterin geçişine herhangi dirençle karşılaşılırsa, yavaşça geri çekin ve nazik bir basınç ile tekrar ilerlemek. Kateterin Nazik rotasyon sol ventrikül içine yerleştirme ile yardımcı olabilir. Iletkenlik kateter zorlamak ciddi kardiyovasküler komplikasyon veya kateter zarar görmesine neden olabilir. </li><li> Kayıt bazal basınç-hacim ~ 10 kateter yerleştirildikten sonra min ve kararlı bir duruma ulaşmak (Şekil 2) döngüler. </li></ol></li><li> Apikal Yaklaşım <ol><li> Bir anestezi ve havalandırmalı fare, bir kesi yapmak from kılıç şeklinde süreci ve diyafram görünür yanal kadar göğüs duvarından kesti. </li><li> Diyaframın olsa kesin ve kalbin apeks görselleştirmek. </li><li> Yakın elektrot sadece ventrikül içinde kadar, (25-30 G iğne kullanarak) bir iğne bıçak yarası ile sol ventrikül apeksi içine iletkenlik kateter yerleştirin. </li><li> Kayıt bazal basınç-hacim ~ 10 kateter yerleştirildikten sonra min ve kararlı bir devlet elde döngüler. </li></ol></li></ol> Geçici Aort Occlusion Kullanılması 4. Değişen art yük <ol><li> Geçici aort tıkanıklığı gerçekleştirmek için, göğsün üst kısmında küçük bir yatay bir kesi yapmak ve enine aorta maruz doku çevresindeki teşrih. </li><li> Enine aort altında 6-0 ipek bitişik harfleri yerleştirin. Basınç-volüm eğrileri başlangıca geri döndü sonra, hafifçe ve yavaşça, bir iğne kelepçesi ile sütür iki ucunu toka 1-2 sn boyunca dikiş yükseltmek ve yavaşça serbest gerginlik. </li&gt; <li> Üç ayrı optimum kayıtları aynı hayvandan yapılana kadar, bu işlemi tekrarlayın. Not: Optimal kayıtları en az 5 basınç volüm döngüleri ve sütür (Şekil 3A ve 3C) hakkında gerginlik uygulama sırasında uç sistolik basınçlarında sürekli bir artış olmalıdır. </li></ol> 5. Değişen Preload Geçici İnferior Vena Kava Occlusion Kullanma (IVC) <ol><li> Geçici inferior vena kava tıkanıklığı gerçekleştirmek için, IVC maruz diyaframın altında, kılıç şeklinde bir süreç altında yatay bir kesi yapmak. </li><li> IVC altında 6-0 ipek bitişik harfleri yerleştirin. Basınç-volüm eğrileri başlangıca geri döndü sonra, bir iğne kelepçesi ile sütür iki ucunu toka; ve yavaşça 1-2 saniye boyunca dikiş yükseltmek ve yavaşça serbest gerginlik. IVC oklüzyonu da çubukla uçlu pamuk kullanarak basınç hassas bir uygulama tarafından gerçekleştirilebilmektedir. </li><li> Üç ayrı optimum kayıtlar m kadar bu işlemi tekrarlayınAynı hayvandan ade. Not: Optimal kayıtları en az 5 basınç volüm döngüleri ve dikiş üzerindeki gerginlik uygulama sırasında sol ventrikül diyastol sonu basınçları sürekli bir düşüş olması gerekir (Şekil 4A ve 4B). </li></ol> 6. Tuzlu Kalibrasyon <ol><li> Çalışmanın sonunda, bir paralel iletkenlik (V p) değeri juguler ven yoluyla hayvana hipertonik salin (% 15) bir 10 ul bolus enjekte edilerek elde olması (Şekil 5A ve 5B) olabilir. Not: Bu, bolus basıncında herhangi bir değişiklik yapılmadan hacminde belirgin bir artışa neden olur. Bu tür bir hacim belirgin değişiklik nedeniyle hacim gerçek bir artış kan havuzu iletkenlik yerine bir değişiklik sonucudur. Hipertonik salin bir negatif inotropik etkiye sahip olduğu 13 dP / dt max geçici bir düşüş, görülebilir. Hesaplanan V p boyunca basınç volüm analizi yazılımı içine girilebilirKüvet kalibrasyon parametreleri ile ve mikrolitre RVUs dönüştürmek için. </li></ol> 7. Cuvette Kalibrasyon <ol><li> Bir küvet kalibrasyonu gerçekleştirmek için, ° C 37 ° C&#39;de ısıtıldı, bir ısıtma yastığı ya da bir su banyosu üzerinde, üretici tarafından tedarik edilen bilinen çaplar oyuklarına sahip bir küvet kullanır. Hemodinamik değerlendirmeler geçiren farelerin taze sıcak heparinize kan ilk 4-5 delik doldurun. Not: Bir küvet kalibrasyon fare kanı kullanılarak sol ventrikül kan havuzunun doğru değerlendirilmesi için izin verir ve mikrolitre RVUs gelen hacimli veri dönüşüm sağlar. </li><li> Tüm elektrotlar batık kadar, ilk kuyunun içine iletkenlik kateter yerleştirin. Yavaşça değişen RVUs üretecek olan kuyuda kateter hareket ettirin. </li><li> RVUs hacmi kanalında iletkenlik değişiklikleri kaydedin. Kalibrasyon için, en yüksek RVU seçin. Not: deliklerin hacim ya volum için bir denklem kullanılarak) 1 ile hesaplanabiliryarıçapı küvet oyuk ve uzunluk olduğu bir silindirin, e Dahili iki algılama elektrotlar veya 2), üretici talimatlarına kontrol arasındaki uzunluğuna bağlıdır. Iletkenlik çıkış mikrolitre 11 içine RVUs veri dönüştüren bir kalibrasyon ifadesinin bilinen hacmi ile korele edilebilir. </li></ol> 8. Ötenazi <ol><li> Protokolün sonunda, fareler anestezi altında iken servikal dislokasyon ile ötenazi. </li><li> Sağlamak amacıyla ölüm, uygulanan servikal dislokasyon sahip fareler ötenazi ikincil bir yöntem geçmesi gerekir. Biz anestezi altında deney için kalp dokusunun hasat veya iki taraflı torakotomi ile, anestezi altında kansız kullanın. </li></ol> 9. Veri Analizi kullanılarak Basınç Hacim Döngüsü Analizi Yazılımı <ol><li> Tuzlu Kalibrasyon V p hesaplayın <ol><li> Seçin basınç ve VOLUBeni hipertonik salin ejeksiyon sırasında elde edilen döngüler (Şekil 5A ve 5B) </li><li> İhracat basınç hacim analiz yazılımı döngüler. Tuzlu kalibrasyon için seçeneği seçin (Şekil 5C) </li><li> Hesaplanan V p değeri (Şekil 5D) kaydedin. Not: V p değeri tuzlu kalibrasyona sonu sistolik hacim vs 1) End-diyastolik hacim kesişimi belirlenmesi ve 2) sonu diyastolik hacim = Sonu sistolik hacim çizgisi ile hesaplanır. Bu satırların kesiştiği basıncı volüm analiz yazılımı tarafından hesaplanan V s sağlar. </li></ol></li><li> Hacmine iletkenlik girin (RVU) hacim kanal seçenekleri ilişki (Şekil 1F) </li><li> Temel Basınç Hacim döngü ilişkisini ölçmek <ol><li> Kararlı durum elde edildikten sonra basınç ve hacim kanalları 8-10 kardiyak döngülerini seçin (Şekil 2A) ve yumuşak analize ihracatware. 5-6 ekspiryum sonu döngüler (Şekil 2B) tespit </li><li> Paralel iletkenlik düzeltmek için V p değerini kullanın. &quot;Kararlı Durum&quot; seçeneğini seçin ve bir hemodinamik özet tablo oluşturmak (Şekil 2C) </li></ol></li><li> Aort Konstrüksiyon sırasında Tedbir Basınç Hacim döngü İlişkisi <ol><li> Diyastol sonu basınçları (Şekil 3A) ve analiz yazılımları ihracat artışı öncesinde aort daralma karşılık basınç ve hacim kanalları 8-10 kalp döngüleri seçin. 5-6 ekspiryum sonu döngüler (Şekil 3C) tespit </li><li> Sonu Sistolik Basınç Hacim İlişkisi hesaplar Seç &quot;Kasılma&quot; analizi (Şekil 3B), (ESPVR) </li></ol></li><li> VKİ Konstrüksiyon sırasında Tedbir Basınç Hacim döngü İlişkisi <ol><li> (Figür IVC daralma karşılık basınç ve hacim kanalları 8-10 kardiyak döngüleri seçinanaliz yazılımı, e 4A) ve ihracat. 5-6 ekspiryum sonu döngüler (Şekil 4B) tespit </li><li> &quot;Kasılma&quot; analizi Preload askere almalarla İnme Çalışma hesaplar (Şekil 3B), (PRSW) (Şekil 4C) seçin, EDV (Şekil 4D), yanı sıra ESPVR ve sonu diyastolik basınç hacim ilişkisi vs dt Maksimum dP / (Şekil 4E) </li></ol></li></ol>

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T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sensitivity+of+left+ventricular+end-systolic+pressure-volume+relation+to+type+of+loading+intervention+in+dogs.">Sensitivity of left ventricular end-systolic pressure-volume relation to type of loading intervention in dogs.</a> Circ Res. 62 (6), 1247-1258 (1988).</li><li>Wei, C. L., 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=Volume+catheter+parallel+conductance+varies+between+end-systole+and+end-diastole.">Volume catheter parallel conductance varies between end-systole and end-diastole.</a> IEEE Trans Biomed Eng. 54 (8), 1480-1489 (2007).</li><li>Porterfield, J. E., 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=Dynamic+correction+for+parallel+conductance,+GP,+and+gain+factor,+alpha,+in+invasive+murine+left+ventricular+volume+measurements.">Dynamic correction for parallel conductance, GP, and gain factor, alpha, in invasive murine left ventricular volume measurements.</a> J Appl Physiol (1985). 107 (6), 1693-1703 (2009).</li></ol>

Yazarlar ifşa hiçbir şey yok.

Biz kardiyak kontraktilite ve rahatlama hem de kapsamlı analizler elde etmek, farelerde bir iletkenlik kateter kullanılarak basınç-hacim döngü analizi perfoming için bir yöntem açıklanmaktadır. Suga, Sagawa ve arkadaşları basınç-volüm kardiyak kontraktilite önlemleri özellikle ESPVR eğimini veya sistol sonu elastans (E es) ve E max tanımlamak için döngüler kullanılır. Hacminin (P / V) basınç oranı ile tanımlanır elastisite, sistol süresi boyunca değişir. Her sistol ...

Kardiyak basınç volüm analizi kalp fonksiyonu ayrıntılı bilgi sağlar ve fonksiyonel değerlendirme 1 altın standarttır. Böyle ekokardiyografi veya kardiyak MR gibi görüntüleme teknikleri, fonksiyonel tedbirleri sağlarken, bu önlemlerin yükleme koşulları son derece bağımlıdırlar. Kalp kontraktilite ve gevşeme Yük bağımsız önlemler ön ve son yüklerin aralığında ventriküler basınç ve hacim ilişkisi dinamik ölçümlerini gerektirmektedir. Basınç-hacim ilişkisi Bu anlayış Sagawa ve arkadaşları 2,3 çığır açan çalışmalarından kaynaklanmaktadır. Bunlar basınç-hacim döngü türetilmiş kontraktilite önlemleri yükleme koşulları 4 bağımsız olduğunu ex vivo olarak perfüze köpek kalplerinde gösterdi. Bu analizlerin in vivo uygulamasında 1980&#39;lerde iletkenliği kateter geliştirilmesi ile mümkün oldu. Ka izin Bu teknik ilerlemess ve arkadaşları insanlarda 5,6 basınç-volüm halkası analizi gerçekleştirmek için. Geç 1990 7 iletkenlik kateter ve cerrahi tekniklerdeki gelişmeler minyatürleştirilmesi yapılacak genetik ve farmakolojik çalışmalar için izin kemirgen kalp fonksiyonunun analizi mümkün yaptı. Bu peşin basınç-volüm döngü analizi yaygın kullanımı kurşun beri vardır ve memeli kalp fizyolojisi içgörü büyük bir üretti. Iletkenlik kateter kullanımı ve ondan elde edilen verilerin yorumlanması bir anahtar kavram hacmi ve iletkenlik arasındaki ilişkidir. İletkenlik ters proksimale yerleştirilen elektrotlar, genellikle LV apeks 8&#39;de, aort kapak altına yerleştirilir ve distalde bir kateter kullanılarak ölçülür gerilime ile ilgilidir. Voltaj veya iletkenlikteki değişimler proksimal uzak elektrot akan akım değişiklikleri ile ölçülür. Kan havuzu katkıda rağmenönemli ölçüde iletkenliğe s, ventriküler duvar katkısı, paralel iletkenlik (V p) olarak adlandırılan, ölçülen iletkenlik mutlak LV volüm ölçümleri elde etmek için çıkarılır olması gerekir. Yöntemler bu düzeltme yapmak için, aşağıdaki protokolde ele alınmaktadır, tuzlu kalibrasyonu denir. Baan ve meslektaşları tarafından açıklanan iletkenlik ve hacim arasındaki matematiksel ilişki, bu hacim = 1 / α olduğunu; (ρ L 2) (GG p), burada α = üniforma alan düzeltme faktörü, ρ = kan direnç, L = elektrotlar arasındaki mesafe, G = iletkenlik ve G p = olmayan kan iletkenliği 9. Not, farelerde üniforma alan düzeltme faktörü nedeniyle küçük odacık hacimleri 10 1.0 yaklaşır. Basınç dönüştürücüler ile birleştiğinde, iletkenlik kateter gerçek zamanlı eşzamanlı basınç ve hacim verileri sağlar. Kardiyak pressuonlar yükleme koşulları ve kalp hızından bağımsız ventrikül fonksiyonu ölçümü için izin verdiği yeniden hacim analizi, kalp fonksiyonunun diğer tedbirler üzerinde özel avantajlar sunuyor. Sonu sistolik basınç hacim ilişkisi (ESPVR) d P / d t max -end-diyastolik volüm ilişkisi, maksimal elastisite (E max) ve askere almalarla inme çalışmaları (PRSW) preload: kontraktilitenin Özgül yük bağımsız kalp endeksleri içerir. Diyastolik fonksiyon bir yük bağımsız önlem diyastol sonu basınç hacim ilişkisi (EDPVR) 11 olduğunu. Aşağıdaki protokol karotis ve apikal yaklaşım her ikisini de kullanarak, kardiyak basınç volüm halkası analizinin yürütülmesini açıklar. Bu çalışmaları gerçekleştirmek için metodoloji detaylı, daha önce 8,11 olarak tarif edilmiş olmasına rağmen, biz de tuzlu ve küvet kalibrasyon düzeltme de dahil olmak üzere hassas basınç-hacim ölçümleri elde etmek önemli adımlar gözden ve thes görsel gösteri sağlayacake prosedürleri. Bu çalışma için yürütülen hayvanlarla Araştırma protokollerle ve onaylanmış Duke Üniversitesi Tıp Merkezi&#39;nin Kurumsal Hayvan Bakım ve Kullanım Kurulu hayvan refahı düzenlemelerine göre ele alınmıştır.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>AnaSed (xylazine)&#160;</td>
			<td>Lloyd Laboratories</td>
			<td>NADA no. 139-236</td>
			<td>Anesthetic</td>
		</tr>
		<tr>
			<td>Ketaset (ketamine)</td>
			<td>Pfizer</td>
			<td>440842</td>
			<td>Anesthetic</td>
		</tr>
		<tr>
			<td>VIP3000</td>
			<td>Matrx Medical Inc.</td>
			<td></td>
			<td>Anesthesia machine</td>
		</tr>
		<tr>
			<td>Ventilator</td>
			<td>Harvard Apparatus</td>
			<td>Model 683</td>
			<td>Surgical Equipment</td>
		</tr>
		<tr>
			<td>Tubing kit</td>
			<td>Harvard Apparatus</td>
			<td>72-1049</td>
			<td>Surgical Equipment</td>
		</tr>
		<tr>
			<td>Homeothermic Blanket&#160;</td>
			<td>Kaz Inc.</td>
			<td>5628</td>
			<td>Surgical Equipment</td>
		</tr>
		<tr>
			<td>Stereo microscope</td>
			<td>Carl Zeiss Optical Inc.</td>
			<td>Stemi 2000</td>
			<td>Surgical Equipment</td>
		</tr>
		<tr>
			<td>Illuminator</td>
			<td>Cole&#8211;Parmer</td>
			<td>41720</td>
			<td>Surgical Equipment</td>
		</tr>
		<tr>
			<td>Dumont no. 55 Dumostar Forceps&#160;</td>
			<td>Fine Science Tools Inc</td>
			<td>11295-51</td>
			<td>Surgical Instruments</td>
		</tr>
		<tr>
			<td>Graefe forceps, curved&#160;</td>
			<td>Fine Science Tools Inc</td>
			<td>11052-10</td>
			<td>Surgical Instruments</td>
		</tr>
		<tr>
			<td>Moria MC31 forceps&#160;</td>
			<td>Fine Science Tools Inc</td>
			<td>11370-31</td>
			<td>Surgical Instruments</td>
		</tr>
		<tr>
			<td>Mayo scissors&#160;</td>
			<td>Fine Science Tools Inc</td>
			<td>14512-15</td>
			<td>Surgical Instruments</td>
		</tr>
		<tr>
			<td>Iris scissors&#160;</td>
			<td>Fine Science Tools Inc</td>
			<td>14041-10</td>
			<td>Surgical Instruments</td>
		</tr>
		<tr>
			<td>Halsey needle holder&#160;</td>
			<td>Fine Science Tools Inc</td>
			<td>12501-13</td>
			<td>Surgical Instruments</td>
		</tr>
		<tr>
			<td>Olsen&#8211;Hegar needle holder&#160;</td>
			<td>Fine Science Tools Inc</td>
			<td>12002-12</td>
			<td>Surgical Instruments</td>
		</tr>
		<tr>
			<td>spring scissors</td>
			<td>Fine Science Tools Inc</td>
			<td>15610-08</td>
			<td>Surgical Instruments</td>
		</tr>
		<tr>
			<td>disposable underpads</td>
			<td>Kendall/Tyco Healthcare</td>
			<td>1038</td>
			<td>Surgical Supplies</td>
		</tr>
		<tr>
			<td>Sterile gauze sponges, sterile&#160;</td>
			<td>Dukal</td>
			<td>62208</td>
			<td>Surgical Supplies</td>
		</tr>
		<tr>
			<td>Cotton-tipped applicators, sterile&#160;</td>
			<td>Solon</td>
			<td>368</td>
			<td>Surgical Supplies</td>
		</tr>
		<tr>
			<td>Surgical suture,&#160; silk, 6-0&#160;</td>
			<td>DemeTECH</td>
			<td>FT-639-1</td>
			<td>Surgical Supplies</td>
		</tr>
		<tr>
			<td>1 cc Insulin syringes&#160;</td>
			<td>Becton Dickenson</td>
			<td>329412</td>
			<td>Surgical Supplies</td>
		</tr>
		<tr>
			<td>Access-9&#8482; Hemostasis Valve</td>
			<td>Merit Medical&#160;</td>
			<td>MAP111</td>
			<td>Hemodynamic equipment</td>
		</tr>
		<tr>
			<td>Sphygmomanometer</td>
			<td>Baumanometer</td>
			<td>320</td>
			<td>Hemodynamic equipment</td>
		</tr>
		<tr>
			<td>Millar PV system MPVS-300/400 or MPVS Ultra (includes calibration cuvette)</td>
			<td>ADInstruments Inc</td>
			<td></td>
			<td>Hemodynamic equipment</td>
		</tr>
		<tr>
			<td>1.4F conductance catheter&#160;</td>
			<td>ADInstruments Inc</td>
			<td>SPR-839</td>
			<td>Hemodynamic equipment</td>
		</tr>
		<tr>
			<td>PowerLab 4/30 with Chart Pro</td>
			<td>ADInstruments Inc.</td>
			<td>ML866/P</td>
			<td>Hemodynamic software</td>
		</tr>
		<tr>
			<td>animal clipper</td>
			<td>Wahl</td>
			<td>8787-450A</td>
			<td>Miscellaneous</td>
		</tr>
		<tr>
			<td>Intradermic tubing PE-10 (Becton Dickinson, cat. no. )</td>
			<td>Becton Dickenson</td>
			<td>427401</td>
			<td>Miscellaneous</td>
		</tr>
		<tr>
			<td>Intradermic tubing PE-50 (Becton Dickinson, cat. no.)</td>
			<td>Becton Dickenson</td>
			<td>427411</td>
			<td>Miscellaneous</td>
		</tr>
		<tr>
			<td>Needle assortment (18, 25 and 30 gauge; Thomas Scientific)</td>
			<td></td>
			<td></td>
			<td>Miscellaneous</td>
		</tr>
		<tr>
			<td>0.9% (wt/vol) sodium chloride injection, USP , cat. no. )</td>
			<td>Hospira</td>
			<td>NDC no. 0409-4888-50</td>
			<td>Miscellaneous</td>
		</tr>
		<tr>
			<td>Surgical tape</td>
			<td></td>
			<td></td>
			<td>Miscellaneous</td>
		</tr>
		<tr>
			<td>Alconox (Alconox Inc.) for catheter cleaning</td>
			<td>ADInstruments Inc.</td>
			<td></td>
			<td>Miscellaneous</td>
		</tr>
	</tbody>
</table>

cardiac pressure-volume loop analysis using conductance catheters in mice

Cardiac pressure-volume loop analysis is the &#8220;gold-standard&#8221; in the assessment of load-dependent and load-independent measures of ventricular systolic and diastolic function. Measures of ventricular contractility and compliance are obtained through examination of cardiac response to changes in afterload and preload. These techniques were originally developed nearly three decades ago to measure cardiac function in large mammals and humans. The application of these analyses to small mammals, such as mice, has been accomplished through the optimization of microsurgical techniques and creation of conductance catheters. Conductance catheters allow for estimation of the blood pool by exploiting the relationship between electrical conductance and volume. When properly performed, these techniques allow for testing of cardiac function in genetic mutant mouse models or in drug treatment studies. The accuracy and precision of these studies are dependent on careful attention to the calibration of instruments, systematic conduct of hemodynamic measurements and data analyses. We will review the methods of conducting pressure-volume loop experiments using a conductance catheter in mice.

Basınç-hacim döngü yöntemi, ilaç çalışmaları 16 uygulanan genetik olarak tadil edilmiş fareler 14,15 veya farelerde kalp fonksiyonu ölçmek için kullanılabilir. Temsili basınç hacim döngüler ß-arrestin etkisini araştıran daha önce yayınlanmış çalışmaları 16 sağlanmaktadır TRV120023, AT1R ligand önyargılı. TRV120023 in vivo kardiyak fonksiyonları etkiler olup olmadığını sınamak için, basınç-volüm döngü analizi konvansiyonel v...

Watch this Scientific Journal Video about Cardiac Pressure-Volume Loop Analysis Using Conductance Catheters in Mice at JoVE.com

Cardiac Pressure-Volume Loop Analysis Using Conductance Catheters in Mice

Cardiac pressure-volume loop analysis is the most comprehensive way to measure cardiac function in the intact heart. We describe a technique to perform and analyze cardiac pressure volume loops, using conductance catheters.

Farelerde İletkenlik Balon Kullanımı kalp Basınç Hacim Döngüsü Analizi

Cardiac pressure-volume loop analysis is the &#8220;gold-standard&#8221; in the assessment of load-dependent and load-independent measures of ventricular ...

cardiac-pressure-volume-loop-analysis-using-conductance-catheters

Research

JoVE Journal

Biology

19.3K Görüntüleme.  Duke University Medical Center. Cardiac pressure-volume loop analysis is the most comprehensive way to measure cardiac function in the intact heart. We describe a technique to perform and analyze cardiac pressure volume loops, using conductance catheters. 

Video: Cardiac Pressure-Volume Loop Analysis Using Conductance Catheters in Mice

Patch Clamp and Perfusion Techniques for Studying Ion Channels Expressed in Xenopus oocytes

The protocol presented here is designed to study the activation of the large conductance, voltage- and Ca2+-activated K+ (BK) channels. The protocol may also be used to study the structure-function relationship for other ion channels and neurotransmitter receptors1. BK channels are widely expressed in different tissues and have been implicated in many physiological functions, including regulation of smooth muscle contraction, frequency tuning of inner hair cells and regulation of neurotransmitter release2-6. BK channels are activated by membrane depolarization and by intracellular Ca2+ and Mg2+ 6-9. Therefore, the protocol is designed to control both the membrane voltage and the intracellular solution. In this protocol, messenger RNA of BK channels is injected into Xenopus laevis oocytes (stage V-VI) followed by 2-5 days of incubation at 18&deg;C10-13. Membrane patches that contain single or multiple BK channels are excised with the inside-out configuration using patch clamp techniques10-13. The intracellular side of the patch is perfused with desired solutions during recording so that the channel activation under different conditions can be examined. To summarize, the mRNA of BK channels is injected into Xenopus laevis oocytes to express channel proteins on the oocyte membrane; patch clamp techniques are used to record currents flowing through the channels under controlled voltage and intracellular solutions.

Patch Clamp and Perfusion Techniques for Studying Ion Channels Expressed in Xenopus oocytes

Ionic current of BK channels is recorded using patch clamp techniques. BK channels are expressed in Xenopus oocytes by injecting messenger RNA. The intracellular solution during patch clamp recordings is controlled by a perfusion system.

İyon Kanalları incelenmesi için yama Kelepçe ve Perfüzyon Teknikleri cinsinden ifade edilir Xenopus Oosit

The protocol presented here is designed to study the activation of the large conductance, voltage- and Ca2+-activated K+ (BK) channels. The protocol may ...

Biyoloji

Bioengineering Human Microvascular Networks in Immunodeficient Mice

The future of tissue engineering and cell-based therapies for tissue regeneration will likely rely on our ability to generate functional vascular networks in vivo. In this regard, the search for experimental models to build blood vessel networks in vivo is of utmost importance 1. The feasibility of bioengineering microvascular networks in vivo was first shown using human tissue-derived mature endothelial cells (ECs) 2-4; however, such autologous endothelial cells present problems for wide clinical use, because they are difficult to obtain in sufficient quantities and require harvesting from existing vasculature. These limitations have instigated the search for other sources of ECs. The identification of endothelial colony-forming cells (ECFCs) in blood presented an opportunity to non-invasively obtain ECs 5-7. We and other authors have shown that adult and cord blood-derived ECFCs have the capacity to form functional vascular networks in vivo 7-11. Importantly, these studies have also shown that to obtain stable and durable vascular networks, ECFCs require co-implantation with perivascular cells. The assay we describe here illustrates this concept: we show how human cord blood-derived ECFCs can be combined with bone marrow-derived mesenchymal stem cells (MSCs) as a single cell suspension in a collagen/fibronectin/fibrinogen gel to form a functional human vascular network within 7 days after implantation into an immunodeficient mouse. The presence of human ECFC-lined lumens containing host erythrocytes can be seen throughout the implants indicating not only the formation (de novo) of a vascular network, but also the development of functional anastomoses with the host circulatory system. This murine model of bioengineered human vascular network is ideally suited for studies on the cellular and molecular mechanisms of human vascular network formation and for the development of strategies to vascularize engineered tissues.

Here, we describe a methodology to deliver human cord blood-derived endothelial colony-forming cells (ECFCs) and bone marrow-derived mesenchymal stem cells (MSCs), embedded in a collagen/fibronectin gel, subcutaneously into immunodeficient mice. This cell/gel combination generates a human vascular network that connects with the mouse vasculature.

Bağışık yetmezliği olan farelere Biyomühendislik İnsan Mikrovasküler Ağları

The future of tissue engineering and cell-based therapies for tissue regeneration will likely rely on our ability to generate functional vascular networks ...

Expression and Purification of the Cystic Fibrosis Transmembrane Conductance Regulator Protein in Saccharomyces cerevisiae

The cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride channel, that when mutated, can give rise to cystic fibrosis in humans.There is therefore considerable interest in this protein, but efforts to study its structure and activity have been hampered by the difficulty of expressing and purifying sufficient amounts of the protein1-3. Like many 'difficult' eukaryotic membrane proteins, expression in a fast-growing organism is desirable, but challenging, and in the yeast S. cerevisiae, so far low amounts were obtained and rapid degradation of the recombinant protein was observed 4-9. Proteins involved in the processing of recombinant CFTR in yeast have been described6-9 .In this report we describe a methodology for expression of CFTR in yeast and its purification in significant amounts. The protocol describes how the earlier proteolysis problems can be overcome and how expression levels of CFTR can be greatly improved by modifying the cell growth conditions and by controlling the induction conditions, in particular the time period prior to cell harvesting. The reagants associated with this protocol (murine CFTR-expressing yeast cells or yeast plasmids) will be distributed via the US Cystic Fibrosis Foundation, which has sponsored the research. An article describing the design and synthesis of the CFTR construct employed in this report will be published separately (Urbatsch, I.; Thibodeau, P. et al., unpublished). In this article we will explain our method beginning with the transformation of the yeast cells with the CFTR construct - containing yeast plasmid (Fig. 1). The construct has a green fluorescent protein (GFP) sequence fused to CFTR at its C-terminus and follows the system developed by Drew et al. (2008)10. The GFP allows the expression and purification of CFTR to be followed relatively easily. The JoVE visualized protocol finishes after the preparation of microsomes from the yeast cells, although we include some suggestions for purification of the protein from the microsomes. Readers may wish to add their own modifications to the microsome purification procedure, dependent on the final experiments to be carried out with the protein and the local equipment available to them. The yeast-expressed CFTR protein can be partially purified using metal ion affinity chromatography, using an intrinsic polyhistidine purification tag. Subsequent size-exclusion chromatography yields a protein that appears to be &gt;90% pure, as judged by SDS-PAGE and Coomassie-staining of the gel.

Expression and Purification of the Cystic Fibrosis Transmembrane Conductance Regulator Protein in Saccharomyces cerevisiae

Attempts to express the cystic fibrosis transmembrane conductance regulator (CFTR) in Saccharomyces cerevisiae have, until now, yielded relatively low amounts of protein. This protocol and the associated reagents distributed via the Cystic Fibrosis Foundation should allow the preparation of milligram amounts of this 'difficult' eukaryotic membrane protein.

Yılında Kistik Fibrozis Transmembran İletkenlik Regülatörü Protein İfadesi ve Arıtma Saccharomyces cerevisiae

The  cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride  channel, that when mutated, can give rise to cystic fibrosis in  ...

Measurement of Leaf Hydraulic Conductance and Stomatal Conductance and Their Responses to Irradiance and Dehydration Using the Evaporative Flux Method (EFM)

Water is a key resource, and the plant water transport system sets limits on maximum growth and drought tolerance. When plants open their stomata to achieve a high stomatal conductance (gs) to capture CO2 for photosynthesis, water is lost by transpiration1,2. Water evaporating from the airspaces is replaced from cell walls, in turn drawing water from the xylem of leaf veins, in turn drawing from xylem in the stems and roots. As water is pulled through the system, it experiences hydraulic resistance, creating tension throughout the system and a low leaf water potential (&Psi;leaf). The leaf itself is a critical bottleneck in the whole plant system, accounting for on average 30% of the plant hydraulic resistance3. Leaf hydraulic conductance (Kleaf = 1/ leaf hydraulic resistance) is the ratio of the water flow rate to the water potential gradient across the leaf, and summarizes the behavior of a complex system: water moves through the petiole and through several orders of veins, exits into the bundle sheath and passes through or around mesophyll cells before evaporating into the airspace and being transpired from the stomata. Kleaf is of strong interest as an important physiological trait to compare species, quantifying the effectiveness of the leaf structure and physiology for water transport, and a key variable to investigate for its relationship to variation in structure (e.g., in leaf venation architecture) and its impacts on photosynthetic gas exchange. Further, Kleaf responds strongly to the internal and external leaf environment3. Kleaf can increase dramatically with irradiance apparently due to changes in the expression and activation of aquaporins, the proteins involved in water transport through membranes4, and Kleaf declines strongly during drought, due to cavitation and/or collapse of xylem conduits, and/or loss of permeability in the extra-xylem tissues due to mesophyll and bundle sheath cell shrinkage or aquaporin deactivation5-10. Because Kleaf can constrain gs and photosynthetic rate across species in well watered conditions and during drought, and thus limit whole-plant performance they may possibly determine species distributions especially as droughts increase in frequency and severity11-14.
We present a simple method for simultaneous determination of Kleaf and gs on excised leaves. A transpiring leaf is connected by its petiole to tubing running to a water source on a balance. The loss of water from the balance is recorded to calculate the flow rate through the leaf. When steady state transpiration (E, mmol &bull; m-2 &bull; s-1) is reached, gs is determined by dividing by vapor pressure deficit, and Kleaf by dividing by the water potential driving force determined using a pressure chamber (Kleaf= E /- &Delta;&psi;leaf, MPa)15.
This method can be used to assess Kleaf responses to different irradiances and the vulnerability of Kleaf to dehydration14,16,17.

Measurement of Leaf Hydraulic Conductance and Stomatal Conductance and Their Responses to Irradiance and Dehydration Using the Evaporative Flux Method EFM

We describe a relatively rapid (30 min) and realistic method for simultaneously measurement of leaf hydraulic conductance (Kleaf) and stomatal conductance (gs) for transpiring excised leaves. The method can be modified to measure the light and dehydration responses of Kleaf and gs.

Evaporatif Akı Yöntemi (EFM) kullanarak Işınım ve Dehidrasyon için Yaprak Hidrolik İletkenlik ve Stoma İletkenlik ve Yanıtları Ölçümü

Water is a key resource, and the plant water transport system sets limits on maximum growth and drought tolerance. When plants open their stomata to ...

Intravital Microscopy of the Microcirculation in the Mouse Cremaster Muscle for the Analysis of Peripheral Stem Cell Migration

In the era of intravascular cell application protocols in the context of regenerative cell therapy, the underlying mechanisms of stem cell migration to nonmarrow tissue have not been completely clarified. We describe here the technique of intravital microscopy applied to the mouse cremaster microcirculation for analysis of peripheral bone marrow stem cell migration in vivo. Intravital microscopy of the M. cremaster has been previously introduced in the field of inflammatory research for direct observation of leucocyte interaction with the vascular endothelium. Since sufficient peripheral stem and progenitor cell migration includes similar initial steps of rolling along and firm adhesion at the endothelial lining it is conceivable to apply the M. cremaster model for the observation and quantification of the interaction of intravasculary administered stem cells with the endothelium. As various chemical components can be selectively applied to the target tissue by simple superfusion techniques, it is possible to establish essential microenvironmental preconditions, for initial stem cell recruitment to take place in a living organism outside the bone marrow.

Intravital microscopy of the mouse M. cremaster microcirculation offers a unique and well-standardized in vivo model for the analysis of peripheral bone marrow stem cell migration.

Periferik Kök Hücre Göç Analizi Fare Cremaster Muscle Mikrosirkülasyon Intravital Mikroskopi

In the era of intravascular cell application protocols in the context of regenerative cell therapy, the underlying mechanisms of stem cell migration to ...

Purification of the Cystic Fibrosis Transmembrane Conductance Regulator Protein Expressed in Saccharomyces cerevisiae

Defects in the cystic fibrosis transmembrane conductance regulator (CFTR) protein cause cystic fibrosis (CF), an autosomal recessive disease that currently limits the average life expectancy of sufferers to &#60;40 years of age. The development of novel drug molecules to restore the activity of CFTR is an important goal in the treatment CF, and the isolation of functionally active CFTR is a useful step towards achieving this goal.
We describe two methods for the purification of CFTR from a eukaryotic heterologous expression system, S. cerevisiae. Like prokaryotic systems, S. cerevisiae can be rapidly grown in the lab at low cost, but can also traffic and posttranslationally modify large membrane proteins. The selection of detergents for solubilization and purification is a critical step in the purification of any membrane protein. Having screened for the solubility of CFTR in several detergents, we have chosen two contrasting detergents for use in the purification that allow the final CFTR preparation to be tailored to the subsequently planned experiments.
In this method, we provide comparison of the purification of CFTR in dodecyl-&#946;-D-maltoside (DDM) and 1-tetradecanoyl-sn-glycero-3-phospho-(1&#39;-rac-glycerol) (LPG-14). Protein purified in DDM by this method shows ATPase activity in functional assays. Protein purified in LPG-14 shows high purity and yield, can be employed to study post-translational modifications, and can be used for structural methods such as small-angle X-ray scattering and electron microscopy. However it displays significantly lower ATPase activity.

Purification of the Cystic Fibrosis Transmembrane Conductance Regulator Protein Expressed in Saccharomyces cerevisiae

Heterologous expression and purification of the cystic fibrosis transmembrane conductance regulator (CFTR) are significant challenges and limiting factors in the development of drug therapies for cystic fibrosis. This protocol describes two methods for the isolation of milligram quantities of CFTR suitable for functional and structural studies.&#160;

Olarak ifade edilmiştir kistik fibroz transmembran kondüktans regülatörü Protein Saflaştırılması<em&gt; Saccharomyces cerevisiae</em

Defects in the cystic fibrosis transmembrane conductance regulator (CFTR) protein cause cystic fibrosis (CF), an autosomal recessive disease that ...

A New Technique for Quantitative Analysis of Hair Loss in Mice Using Grayscale Analysis

Alopecia is a common form of hair loss which can occur in many different conditions, including male-pattern hair loss, polycystic ovarian syndrome, and alopecia areata. Alopecia can also occur as a side effect of chemotherapy in cancer patients. In this study, our goal was to develop a consistent and reliable method to quantify hair loss in mice, which will allow investigators to accurately assess and compare new therapeutic approaches for these various forms of alopecia. The method utilizes a standard gel imager to obtain and process images of mice, measuring the light absorption, which occurs in rough proportion to the amount of black (or gray) hair on the mouse. Data that has been quantified in this fashion can then be analyzed using standard statistical techniques (i.e., ANOVA, T-test). This methodology was tested in mouse models of chemotherapy-induced alopecia, alopecia areata and alopecia from waxing. In this report, the detailed protocol is presented for performing these measurements, including validation data from C57BL/6 and C3H/HeJ strains of mice. This new technique offers a number of advantages, including relative simplicity of application, reliance on equipment which is readily available in most research laboratories, and applying an objective, quantitative assessment which is more robust than subjective evaluations. Improvements in quantification of hair growth in mice will improve study of alopecia models and facilitate evaluation of promising new therapies in preclinical studies.

Alopecia is a common form of hair loss which can occur in many different conditions, including as a side-effect of chemotherapy. We have developed a method to quantify hair loss in mice, utilizing a standard gel imager to perform a grayscale analysis, to facilitate study of promising new alopecia therapies.

Gri tonlama Analizi İle Farelerde Saç Dökülmesi Kantitatif Analiz Yeni Bir Teknik

Alopecia is a common form of hair loss which can occur in many different conditions, including male-pattern hair loss, polycystic ovarian syndrome, and ...

Relating Stomatal Conductance to Leaf Functional Traits

Leaf functional traits are important because they reflect physiological functions, such as transpiration and carbon assimilation. In particular, morphological leaf traits have the potential to summarize plants strategies in terms of water use efficiency, growth pattern and nutrient use. The leaf economics spectrum (LES) is a recognized framework in functional plant ecology and reflects a gradient of increasing specific leaf area (SLA), leaf nitrogen, phosphorus and cation content, and decreasing leaf dry matter content (LDMC) and carbon nitrogen ratio (CN). The LES describes different strategies ranging from that of short-lived leaves with high photosynthetic capacity per leaf mass to long-lived leaves with low mass-based carbon assimilation rates. However, traits that are not included in the LES might provide additional information on the species&#39; physiology, such as those related to stomatal control. Protocols are presented for a wide range of leaf functional traits, including traits of the LES, but also traits that are independent of the LES. In particular, a new method is introduced that relates the plants&#8217; regulatory behavior in stomatal conductance to vapor pressure deficit. The resulting parameters of stomatal regulation can then be compared to the LES and other plant functional traits. The results show that functional leaf traits of the LES were also valid predictors for the parameters of stomatal regulation. For example, leaf carbon concentration was positively related to the vapor pressure deficit (vpd) at the point of inflection and the maximum of the conductance-vpd curve. However, traits that are not included in the LES added information in explaining parameters of stomatal control: the vpd at the point of inflection of the conductance-vpd curve was lower for species with higher stomatal density and higher stomatal index. Overall, stomata and vein traits were more powerful predictors for explaining stomatal regulation than traits used in the LES.

Unraveling how physiology and morphology are linked allows a deeper understanding of mechanistic functioning of plant leaves. We present both a procedure to derive parameters of stomatal regulation from stomatal conductance measurements and correlations with traditional functional leaf traits.

Yaprak Fonksiyonel Özellikleri için ağıza ait iletkenlik İlişkin

Leaf functional traits are important because they reflect physiological functions, such as transpiration and carbon assimilation. In particular, ...

Contractility Measurements on Isolated Papillary Muscles for the Investigation of Cardiac Inotropy in Mice

Papillary muscle isolated from adult mouse hearts can be used to study cardiac contractility during different physiological/pathological conditions. The contractile characteristics can be evaluated independently of external influences such as vascular tonus or neurohumoral status. It depicts a scientific approach between single cell measurements with isolated cardiac myocytes and in vivo studies like echocardiography. Thus, papillary muscle preparations serve as an excellent model to study cardiac physiology/pathophysiology and can be used for investigations like the modulation by pharmacological agents or the exploration of transgenic animal models. Here, we describe a method of isolating the murine left anterior papillary muscle to investigate cardiac contractility in an organ bath setup. In contrast to a muscle strip preparation isolated from the ventricular wall, the papillary muscle can be prepared in toto without damaging the muscle tissue severely. The organ bath setup consists of several temperature-controlled, gassed and electrode-equipped organ bath chambers. The isolated papillary muscle is fixed in the organ bath chamber and electrically stimulated. The evoked twitch force is recorded using a pressure transducer and parameters such as twitch force amplitude and twitch kinetics are analyzed. Different experimental protocols can be performed to investigate the calcium- and frequency-dependent contractility as well as dose-response curves of contractile agents such as catecholamines or other pharmaceuticals. Additionally, pathologic conditions like acute ischemia can be simulated.

Murine left ventricular papillary muscle can be used to investigate cardiac contractility in vitro. This article describes in detail the isolation and experimental protocols to study cardiac contractile characteristics.

Farelerde Kardiyak inotropiyi Soruşturma İzole papiller Kaslar kontraktilite Ölçümleri

Papillary muscle isolated from adult mouse hearts can be used to study cardiac contractility during different physiological/pathological conditions. The ...

Measuring Pressure Volume Loops in the Mouse

Understanding the causes and progression of heart disease presents a significant challenge to the biomedical community. The genetic flexibility of the mouse provides great potential to explore cardiac function at the molecular level. The mouse&#39;s small size does present some challenges in regards to performing detailed cardiac phenotyping. Miniaturization and other advancements in technology have made many methods of cardiac assessment possible in the mouse. Of these, the simultaneous collection of pressure and volume data provides a detailed picture of cardiac function that is not available through any other modality. Here a detailed procedure for the collection of pressure-volume loop data is described. Included is a discussion of the principles underlying the measurements and the potential sources of error. Anesthetic management and surgical approaches are discussed in great detail as they are both critical to obtaining high quality hemodynamic measurements. The principles of hemodynamic protocol development and relevant aspects of data analysis are also addressed.

This manuscript describes a detailed protocol for the collection of pressure-volume data from the mouse.

Fare Basınç Hacim Döngüler Ölçme

Understanding the causes and progression of heart disease presents a significant challenge to the biomedical community. The genetic flexibility of the ...