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Langendorff heart

Shi-Yun Jin, Jun Huang, Hai-Juan Zhu, Hao Wu, Shi-Jin Xu, Michael G Irwin, Shu-Fang He, Ye Zhang
Remifentanil preconditioning (RPC) exerts protection in normal hearts, but has not been investigated in heart failure. The aim of the present study was to evaluate the effect of RPC in a chronic failing rat heart model and the mechanisms involving mitogen-activated protein kinases (MAPK) and Bcl-2 protein family. The doxorubicin induced failing rat hearts were subjected to 30min ischemia / 120min reperfusion (IR) with or without RPC by using Langendorff apparatus. RPC was induced by three cycles of 5min remifentanil / 5min drug-free perfusion before IR, with three different concentrations: 25, 50 and 100μg/l...
March 17, 2018: European Journal of Pharmacology
Hironori Sagawa, Shinsuke Hoshino, Kengo Yoshioka, Wei-Guang Ding, Mariko Omatsu-Kanbe, Masao Nakagawa, Yoshihiro Maruo, Hiroshi Matsuura
BACKGROUND: In the clinical setting, verapamil is contraindicated in neonates and infants because of the perceived risk of hypotension or bradyarrhythmia. However, it remains unclear whether there is an age-dependent difference in the sensitivity of cardiac L-type Ca2+ channel current (ICa,L ) to inhibition by verapamil. METHODS: Ventricular myocytes were enzymatically dissociated from the hearts of 6 different age groups (0, 7, 14, 21, 28 days and 10-15 weeks) of mice using a similar Langendorff-perfusion method...
March 19, 2018: Pediatric Research
Kensuke Ihara, Koji Sugiyama, Kentaro Takahashi, Masahiro Yamazoe, Tetsuo Sasano, Tetsushi Furukawa
Recent genome-wide association studies targeting atrial fibrillation (AF) have indicated a strong association between the genotype and electrophysiological phenotype in the atria. That encourages us to utilize a genetically-engineered mouse model to elucidate the mechanism of AF. However, it is difficult to evaluate the electrophysiological properties in murine atria due to their small size. This protocol describes the electrophysiological evaluation of atria using an optical mapping system with a high temporal and spatial resolution in Langendorff perfused murine hearts...
February 22, 2018: Journal of Visualized Experiments: JoVE
Ze-Wei Tao, Mohamed Mohamed, Jeffrey G Jacot, Ravi K Birla
Bioengineering cardiac tissue constructs with adult cardiomyocytes may help treat adult heart defects and injury. In this study, we fabricated cardiac tissue constructs by seeding adult rat cardiomyocytes on a fibrin gel matrix and analyzed the electromechanical properties of the formed cardiac tissue constructs. Adult rat cardiomyocytes were isolated with a collagenase type II buffer using an optimized Langendorff perfusion system. Cardiac tissue constructs were fabricated using either indirect plating with cardiomyocytes that were cultured for 1 week and dedifferentiated or with freshly isolated cardiomyocytes...
March 13, 2018: ASAIO Journal: a Peer-reviewed Journal of the American Society for Artificial Internal Organs
Jonathan James Weldrick, Mohammad Abdul-Ghani, Lynn A Megeney, Patrick G Burgon
The capacity to isolate and study single cardiomyocytes has dramatically enhanced our understanding of the fundamental mechanisms of the heart. Currently, two primary methods for the isolation of cardiomyocytes are employed; i) The neonatal isolation protocol and, ii) the Langendorff isolation method. A major limiting feature of both procedures is the inability to isolate cardiomyocytes between 3 days and 3 weeks post-birth. Herein we report the establishment and validation of a new method for the rapid and efficient isolation of mouse cardiomyocytes, regardless of age...
March 13, 2018: Canadian Journal of Physiology and Pharmacology
Wen Pan, Ziqi Yang, Jun Cheng, Cheng Qian, Yanggan Wang
The transmural heterogeneity of the contractility in ventricular muscle has not been well-studied. Here, we investigated the calcium transient and sarcomere contraction/relaxation in the endocardial (Endo) and epicardial (Epi) myocytes. Endo and Epi myocytes were isolated from C57/BL6 mice by Langendorff perfusion. Ca2+ transient and sarcomere contraction/relaxation were recorded simultaneously at different stimulation frequencies using a dual excitation fluorescence photomultiplier system. We found that the Endo myocytes have higher baseline diastolic calcium, significantly larger calcium transient and stronger sarcomere shortening than Epi myocytes...
March 12, 2018: Journal of Cellular Physiology
Naoki Tomii, Masatoshi Yamazaki, Tatsuhiko Arafune, Kaichiro Kamiya, Kazuo Nakazawa, Haruo Honjo, Nitaro Shibata, Ichiro Sakuma
BACKGROUND: The action mechanism of stimulation toward spiral waves (SWs) owing to the complex excitation patterns that occur just after point stimulation has not yet been experimentally clarified. OBJECTIVE: This study sought to test our hypothesis that the effect of capturing excitable gap of SW by stimulation can also be explained as the interaction of original phase singularity (PS) and PSs induced by the stimulation on the wave tail (WT) of the original SW...
March 9, 2018: American Journal of Physiology. Heart and Circulatory Physiology
Hannah J Whittington, Philip J Ostrowski, Debra J McAndrew, Fang Cao, Andrew Shaw, Thomas R Eykyn, Hannah Lake, Jack Tyler, Jurgen E Schneider, Stefan Neubauer, Sevasti Zervou, Craig A Lygate
Aims: Mitochondrial creatine kinase (MtCK) couples ATP production via oxidative phosphorylation to phosphocreatine in the cytosol, which acts as a mobile energy store available for regeneration of ATP at times of high demand. We hypothesised that elevating MtCK would be beneficial in ischaemia-reperfusion (I/R) injury. Methods and Results: Mice were created overexpressing the sarcomeric MtCK gene with αMHC promoter at the Rosa26 locus (MtCK-OE) and compared with wild-type (WT) littermates...
March 2, 2018: Cardiovascular Research
Jovana Jeremic, Tamara Nikolic Turnic, Vladimir Zivkovic, Nevena Jeremic, Isidora Milosavljevic, Ivan Srejovic, Radmila Obrenovic, Snezana Jancic, Milena Rakocevic, Stevan Matic, Dragan Djuric, Vladimir Jakovljevic
This research is designed to test the hypothesis that elevated homocysteine (Hcy) levels in vivo, caused by a deficit in vitamin B complex, promote changes in cardiac function and redox status that lead to heart failure. In order to conduct the study, we used adult male Wistar albino rats (n=30; 4 weeks old; 100±15 g body weight). Hyperhomocysteinemia (HHcy) in these animals was achieved by dietary manipulation. For 4 weeks, the animals were fed with a standard rodent chow (control - CF), a diet enriched in methionine with no deficiency in B vitamins (i...
March 6, 2018: Clinical and Experimental Pharmacology & Physiology
Tian-Rui Yang, Yun-Bo Miao, Rong-Ping Zhang, Jin-Wen Yu
OBJECTIVE: To establish an ex vivo model of myocardial ischemia reperfusion in tree shrews. METHODS: The Langendorff ex vivo heart perfusion system was used to establish the myocardial ischemia reperfusion model in tree shrews with different irrigation and reperfusion time settings. Alanine aminotransferase (ALT), aspartate transaminase (AST) and lactic dehydrogenase (LDH) levels were measured by enzyme-labeled immunosorbent assay, creatine kinase MB (CK-MB) was detected using immunosuppression method, and malondialdehyde was measured with thiobarbital staining method; the infarct size was measured using 2, 3, 5-triphenyltrazoliumchloride (TTC) method...
February 20, 2018: Nan Fang Yi Ke da Xue Xue Bao, Journal of Southern Medical University
Massa Oi, Daniel Donner, Jason Peart, Belinda Beck, Lauren Wendt, John P Headrick, Eugene F du Toit
Statins are effective in management of dyslipidaemia, and a cornerstone of CVD prevention strategies. However, the impacts of their pleiotropic effects on other cardiovascular risk factors and myocardial responses to infarction are not well characterised. We hypothesised that pravastatin treatment in obesity improves lipid profiles, insulin-resistance and myocardial resistance to ischaemia/reperfusion (I/R) injury. Wistar rats were fed a control (C) chow or high carbohydrate and fat diet (HCFD) for 16 weeks with vehicle or pravastatin (prava 7...
March 1, 2018: European Journal of Pharmacology
Yusaku Tamura, Hiroki Kohno, Tomomi Mohri, Yasushi Fujio, Goro Matsumiya
Background: Previously, we have demonstrated the cardioprotective effect of interleukin (IL)-11 in animal models of acute coronary syndrome. In this study, we sought to evaluate its cardioprotective potential during prolonged hypothermic global ischemia and subsequent reperfusion using a rat heart donor model. Methods: IL-11 was administered intravenously 10 minutes before harvesting the rat heart. The hearts were preserved in cold (4 °C) Krebs-Henseleit buffer for 6 hours, and then attached to a Langendorff perfusion apparatus and reperfused with an oxygenated Krebs-Henseleit solution containing IL-11...
January 2018: Annals of Cardiothoracic Surgery
Laura R Bear, Peter R Huntjens, Richard Walton, Olivier Bernus, Ruben Coronel, Rémi Dubois
BACKGROUND: Poor identification of electrical dyssynchrony is postulated to be a major factor contributing to the low success rate for cardiac resynchronization therapy (CRT). OBJECTIVE: To evaluate body surface mapping and electrocardiographic imaging (ECGi) to detect electrical dyssynchrony noninvasively. METHODS: Langendorff-perfused pig hearts (n=11) were suspended in a human torso-shaped tank, with LBBB induced through ablation. Recordings were taken simultaneously from a 108-electrode epicardial sock and 128 electrodes embedded in the tank surface during sinus rhythm and ventricular pacing...
February 22, 2018: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Catherine D E Wilder, Nikoleta Pavlaki, Tutku Dursun, Paul Gyimah, Ellice Caldwell-Dunn, Antonella Ranieri, Hannah R Lewis, Michael J Curtis
BACKGROUND & PURPOSE: Antiarrhythmic β-blockers are used in patients at risk of myocardial ischaemia, but the survival benefit and mechanisms are unclear. We hypothesised that β-blockers do not prevent ventricular fibrillation (VF), but instead inhibit the ability of catecholamines to facilitate ischaemia-induced VF, limiting the scope of their usefulness. EXPERIMENTAL APPROACH: ECGs were analysed from ischaemic Langendorff-perfused rat hearts perfused with adrenoceptor antagonists and/or exogenous catecholamines (313 nM noradrenaline+75 nM adrenaline; CATs) in a blinded and randomised study...
February 23, 2018: British Journal of Pharmacology
Aida Salameh, Roxana Schuster, Ingo Dähnert, Johannes Seeger, Stefan Dhein
Cardioplegic arrest during heart operations is often used in cardiac surgery. During cardioplegia, the heart is subjected to a global ischemia/reperfusion-injury. (-)-epigallocatechin gallate (EGCG), one of the main ingredients of green tea, seems to be beneficial in various cardiac diseases. Therefore, the aim of our study was to evaluate EGCG in a rabbit model of cardioplegic arrest. Twenty four mature Chinchilla rabbits were examined. Rabbit hearts were isolated and perfused according to Langendorff. After induction of cardioplegia (without and with 20 µmol/L EGCG, n = 6 each) the hearts maintained arrested for 90-min...
February 23, 2018: International Journal of Molecular Sciences
A Mahalakshmi, Gino A Kurian
Earlier literature underlines that oxidative stress plays a major role in the pathology of myocardial ischemia-reperfusion (I/R) injury, diabetic cardiomyopathy (DCM), diabetes mellitus (DM), fibrosis and hypertrophy which could adversely affect the normal cardiac function. However, the contributory role of oxidative stress in I/R pathology of heart with pre-existing abnormalities or diseases like DM and DCM remains to be explored. I/R injury was induced in normal (normal diet), DM (normal diet + streptozotocin: multiple low dose of 30mg/kg) and DCM (high fat diet (40% fat) + streptozotocin: multiple low dose of 30mg/kg) rat hearts using Langendorff isolated heart perfusion apparatus...
February 17, 2018: Free Radical Biology & Medicine
Kien Tran, Alexandre Murza, Xavier Sainsily, David Coquerel, Jérôme Côté, Karine Belleville, Lounès Haroune, Jean-Michel Longpré, Robert Dumaine, Dany Salvail, Olivier Lesur, Mannix Auger-Messier, Philippe Sarret, Éric Marsault
The apelin receptor generates increasing interest as a potential target across several cardiovascular indications. However, the short half-life of its cognate ligands, the apelin peptides, is a limiting factor for pharmacological use. In this study, we systematically explored each position of apelin-13 to find the best position to cyclize the peptide, with the goal to improve its stability while optimizing its binding affinity and signaling profile. Macrocyclic analogues showed a remarkably higher stability in rat plasma (half-life > 3 h versus 24 min for Pyr-apelin-13), accompanied with improved affinity (analogue 15, Ki 0...
February 20, 2018: Journal of Medicinal Chemistry
Maryam Mahmoudabady, Milad Haghshenas, Saeed Niazmand
Background: The deleterious effect of oxidative stress on myocardial ischemia-reperfusion (I/R) has already been shown in previous studies. Since Teucrium polium has anti-oxidative and cardio-protective properties, the aim of this study was to investigate the effects of this plant on I/R injuries in the isolated rat heart. Materials and Methods: The myocardial I/R injury of rat was created by Langendorff retrograde perfusion technology. The heart was preperfused with Krebs-Henseleit (K-H) solution containing T...
2018: Advanced Biomedical Research
Hiroki Saito, Shigeo Godo, Saori Sato, Akiyo Ito, Yosuke Ikumi, Shuhei Tanaka, Tomoaki Ida, Shigemoto Fujii, Takaaki Akaike, Hiroaki Shimokawa
AIMS: Nitric oxide (NO) and endothelium-dependent hyperpolarization (EDH) play important roles in maintaining cardiovascular homeostasis. We have previously demonstrated that endothelial NO synthase (eNOS) plays diverse roles depending on vessel size, as a NO generating system in conduit arteries and an EDH-mediated system in resistance arteries, for which caveolin-1 (Cav-1) is involved. However, the physiological role of endothelial Cav-1 in microvessels remains to be elucidated. METHODS AND RESULTS: We newly generated endothelium-specific Cav-1-knockout (eCav-1-KO) mice...
February 2018: Journal of Cardiovascular Pharmacology
Qiming Duan, Yunhui Xu, Pauline V Marck, Jennifer Kalisz, Eric E Morgan, Sandrine V Pierre
Ouabain preconditioning (OPC) initiated by low concentrations of the cardiac glycoside (CG) ouabain binding to Na/K-ATPase is relayed by a unique intracellular signaling and protects cardiac myocytes against ischemia/reperfusion injury. To explore more clinically applicable protocols based on CG properties, we tested whether the FDA-approved CG digoxin could trigger cardioprotective effects comparable with those of ouabain using PC, preconditioning and PostC, postconditioning protocols in the Langendorff-perfused mouse heart subjected to global ischemia and reperfusion...
February 2018: Journal of Cardiovascular Pharmacology
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