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Results 401 - 450 of 2793
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Toma Catalin - - 2007
Erythropoietin (Epo) has anti-apoptotic and pro-angiogenic effects in rodent models of myocardial infarction (MI). We tested the hypothesis that a long-acting Epo derivative (darbepoetin) has a beneficial effect on infarct size and peri-infarct remodeling in a clinically relevant large animal model of ischemia-reperfusion. A human acute MI scenario was simulated ...
Cho Janghyun - - 2007
OBJECTIVE: Previously, we demonstrated that a novel opiate peptide, 2',6'-dimethyl-tyrosine-D-Arg-Phe-Lys-NH2, provided cardioprotection against myocardial stunning in vivo. We subsequently showed that this peptide targeted mitochondria and can scavenge reactive oxygen species. The objective of this study was to determine the role of opioid versus antioxidant activity in cardioprotection. METHODS: We ...
Adams Jose A - - 2007
BACKGROUND: Nitric oxide (NO) is a critical regulator of vascular tone, and signal transduction. NO is produced via three unique synthases (NOS); endothelial (eNOS), and neuronal (nNOS) are both constitutively expressed and inducible (iNOS) produced primarily after stimulation. NO has been implicated during and after ischemia reperfusion injury as both ...
Zhou Xiaoyang - - 2007
OBJECTIVE: The histidine-rich Ca-binding protein (HRC) is a Ca-storage protein in cardiac sarcoplasmic reticulum. Recent transgenic studies revealed that this protein inhibits the maximal rates of sarcoplasmic reticulum Ca-transport, leading to cardiac dysfunction. In view of the role of sarcoplasmic reticulum Ca-cycling in myocardial ischemia/reperfusion injury, we designed this study ...
Ferrera René - - 2007
BACKGROUND: The aim of this study was to evaluate the role of the mitochondrial permeability transition pore (MPTP) in the protection achieved by post-conditioning of hearts submitted to hypothermic cardioplegia and ischemia. METHODS: Isolated rat hearts (n = 30) underwent cold cardioplegia (4 degrees C, Celsior solution) and 8 hours ...
Booth Erin A - - 2007
Previous studies demonstrated the protective effects of estrogen administration in models of cardiovascular disease. However, there is a discrepancy between these data and those from the recent clinical trials with hormone replacement therapy in menopausal women. One possible explanation for the divergent results is the addition of progestin to the ...
Dudek Dariusz - - 2008
BACKGROUND: Time-to-treatment is an important determinant of mortality in primary angioplasty for ST-segment elevation myocardial infarction (STEMI). Thus, the benefits in outcome observed with transferring for primary angioplasty in comparison with on-site thrombolysis may be reduced or even lost when long-distance transportation is required. Even though pharmacological reperfusion might overcome ...
Prasan Ananth M - - 2007
AIMS: Nitric oxide (NO) may modulate myocardial ischaemia/reperfusion (I/R) injury, but effects of hypercholesterolaemia on myocardial NO release during I/R are unknown. METHODS: A NO-specific carbon fibre electrode continuously measured coronary sinus [NO] during 60 min low-flow ischaemia (1 ml/min) and 60 min free reperfusion (I/R) in isolated rabbit hearts. ...
Falk Jessica A - - 2007
AIM OF STUDY: Previous reports note an increase in both reactive oxygen species (ROS) and nitric oxide (*NO) at the onset of myocardial reperfusion. We tested the hypothesis that inhibition of *NO or ROS production at the time of reperfusion improves recovery of post-ischemic myocardial function. METHODS AND MATERIALS: Isolated ...
Sidi Avner - - 2007
OBJECTIVE(S): The effects of hypertonic saline on ventricular function are controversial, whether it is increasing contractility or preload. There are no data, however, on the influence of hypertonic saline in a stunned myocardium. DESIGN: This study was prospective and randomized in order to analyze the effects of hypertonic saline solution ...
Sood Reema - - 2007
Injury to the myocardial tissue due to ischemia and reperfusion occurs because of imbalance between the formation of oxidants and available antioxidants in the heart. Levels of vitamin C (ascorbic acid) and vitamin E (alpha--tocopherol) were evaluated in 52 patients of acute myocardial infarction (AMI) treated by streptokinase. They were ...
Arakawa Masayuki - - 2007
Artificial anti-cell death protein FNK, a Bcl-x(L) derivative with three amino acid-substitutions (Y22F, Q26N, and R165K) has enhanced anti-apoptotic and anti-necrotic activity and facilitates cell survival in many species and cell types. The objectives of this study were (i) to investigate whether the protein conjugated with a protein transduction domain ...
Chen Xuehai - - 2007
BACKGROUND: It is still unclear whether celiprolol, a beta(1)-selective blocker, reduces myocardial infarct size. This study will examine whether celiprolol reduces myocardial infarct size, as well as investigate the mechanisms for its infarct size-reducing effect in rabbits. METHODS AND RESULTS: Japanese white rabbits underwent 30 min of ischemia and 48 ...
Korosoglou Grigorios - - 2007
BACKGROUND: Tissue level reperfusion gauges functional recovery in acute ischemic syndromes. However, its current clinical assessment is based upon visual interpretation of myocardial blush grade (MBG), which is operator dependent. The purpose of the study was to test whether quantification of MBG can enhance the predictive value of visual assessment ...
Kals Jaak - - 2008
Oxidative stress is a crucial pathophysiological mechanism of myocardial ischaemia-reperfusion injury (IRI). We evaluated the cardioprotective effects of a novel glutathione analogue, UPF1 (4-methoxy-L-tyrosinyl-gamma-L-glutamyl-L-cysteinyl-glycine; MW 483.5), on an isolated rat heart model of thirty-minute global ischaemia followed by 90 min of reperfusion. Treatment with UPF1 (1 mg/ml) prior to ischaemia ...
Cohen Michael V - - 2007
BACKGROUND: It is unclear how reperfusion of infarcting hearts with alternating cycles of coronary reperfusion/occlusion attenuates infarction, but prevention of mitochondrial permeability transition pore (MPTP) formation is crucial. Acidosis also suppresses MPTP formation. We tested whether postconditioning protects by maintaining acidosis during early reoxygenation. METHODS AND RESULTS: After 30-minute regional ...
Ueno Takayuki - - 2007
OBJECTIVE: The Myocardial protective effects of taurine (TA) are well known. We investigated the optimal phase of giving taurine to reduce myocardial ischaemia-reperfusion injury in isolated rat hearts. METHODS: Isolated rat hearts were subjected to 20 min of global ischaemia followed by 60 min of reperfusion under three different conditions: ...
Coetzee André - - 2007
OBJECTIVE: An experimental study to examine the effect of verapamil, given into a coronary artery, on reperfusion injury. DESIGN: The study was randomized but not blinded. SETTING: This study was conducted in the animal laboratory of the Department of Anesthesiology and Critical Care in an academic institution. PARTICIPANTS: The study ...
Pimenta Márcio Benedito Palma - - 2007
PURPOSE: The aim of this study was to investigate whether the hind limbs or intestinal tract is the most important initiator of the inflammatory response secondary aortic clamping and hind limb ischemia/reperfusion injury. METHODS: Blood samples of Wistar rats obtained from posterior cava vein, portal vein, and heart cavity during ...
Wang Peipei - - 2007
BACKGROUND: Perioperative myocardial infarction adversely affects survival after cardiac operations. In animal studies Na+/H+ exchange inhibitors protect hearts against ischemia-reperfusion injury, but human trials have failed to consistently show beneficial effects. The aim of this study was to investigate whether the combination of the Na+/H+ exchange inhibitor cariporide and the ...
Wang Xiaoliang - - 2007
In vivo administration of L-arginine at different time points during the course of myocardial ischemia and reperfusion (MI/R) has been shown to differentially regulate postischemic apoptosis. Cardiac function is one of the most important indexes used to judge the degree of myocardial injury. The present study attempted to determine whether ...
Sasaki Hideki - - 2007
OBJECTIVE: Recently, it has been reported that ischemic postconditioning, a brief episode of ischemia-reperfusion performed after prolonged ischemia, can reduce ischemic myocardial injury. However, the effects of ischemic postconditioning on ischemia/reperfusion injury remain unclear. We investigated the effects of brief ischemia-reperfusion before (ischemic preconditioning) and after (ischemic postconditioning) prolonged ischemia ...
Farooq Mohsin - - 2007
The last two decades of the 20th century witnessed continuous evolution in the understanding of the pathophysiology of ST elevation myocardial infarction. In parallel, the management of these patients developed steadily throughout this time and into the early years of the 21st century. From humble beginnings involving oxygen therapy, bed ...
Pabla R - - 2007
The role of nitric oxide (NO) in cardiac pathophysiology remains controversial. According to data from several studies using rat and rabbit isolated hearts, NO is an endogenous cardioprotectant against reperfusion-induced ventricular fibrillation (VF). Thus, if cardiac NO production is abolished by perfusion with L-N(G)-nitro-L-arginine methylester (L-NAME) (100 microM) there is ...
Zhu Z - - 2007
We have investigated the cardioprotective effects of novel tetrahydroisoquinoline nitrobenzylmercaptopurine riboside (NBMPR) analog nucleoside transport (NT) inhibitors, compounds 2 and 4, in isolated perfused rat hearts. Langendorff-perfused heart preparations were subjected to 10 min of treatment with compound 2, compound 4, or vehicle (control) followed by 30 min of global ...
Frangogiannis Nikolaos G - - 2007
BACKGROUND: Cardiac interstitial fibrosis plays an important role in the pathogenesis of ischemic cardiomyopathy, contributing to systolic and diastolic dysfunction. We have recently developed a mouse model of fibrotic noninfarctive cardiomyopathy due to brief repetitive myocardial ischemia and reperfusion. In this model, fibrotic changes are preceded by marked and selective ...
Schaefer U - - 2007
AIM: Reperfusion after myocardial ischaemia is associated with a distinct ischaemia/reperfusion injury. Since ACE-inhibition, beyond its influence on cardiac angiotensin II formation and kinin metabolism, has been shown to be cardioprotective by decreasing leucocyte adhesion and endothelin-1 (ET-1) release, we investigated the effects of intracoronary (i.c.) enalaprilat during primary angioplasty ...
Kawasumi Hisashi - - 2007
The cardioprotective effect of caldaret, a novel intracellular Ca(2+) handling modulator that acts through reverse-mode Na(+)/Ca(2+) exchanger inhibition and potential sarcoplasmic reticulum (SR) Ca(2+) uptake enhancement, against reperfusion injury was investigated. We employed a canine model of myocardial infarction induced by 90-min occlusion of left circumflex (LCX) coronary artery followed ...
Baks Timo - - 2007
The purpose of this study was to evaluate the utility of delayed enhancement 64-MDCT in the assessment of myocardial infarct size in a porcine model of acute reperfused myocardial infarction. CT can be used for noninvasive assessment of coronary artery stenosis, but to our knowledge, evaluation of myocardial viability in ...
Nicolosi Alfred C - - 2007
OBJECTIVES: The lanthanide cation, gadolinium (Gd(3+)), accelerates recovery of stunned myocardium when given prior to ischemia. This study sought to determine whether giving Gd(3+) during ischemia or during reperfusion also ameliorates stunning, as these temporal relationships could help determine the clinical utility of this novel agent. METHODS: Regional myocardial stunning ...
Hamid Shabaz A - - 2007
Intracellular signal transduction events in reperfusion following ischemia influence myocardial infarct development. Here we investigate the role of Rho kinase (ROCK) activation as a specific injury signal during reperfusion via attenuation of the reperfusion injury salvage kinase (RISK) pathway phosphatidylinositol 3-kinase (PI3K)/Akt/endothelial nitric oxide (NO) synthase (eNOS). Rat isolated hearts ...
Lujan Heidi L - - 2007
Reperfusion after a brief period of cardiac ischemia can lead to potentially lethal arrhythmias. Clinical observations and experimental work with animals suggest that acupuncture may have therapeutic effects for individuals with coronary heart disease, certain arrhythmias, and myocardial ischemia. Therefore, we tested the hypothesis that electroacupuncture reduces the susceptibility to ...
Yildirim Imren
Complement-1 esterase inhibitor (C1-INH), an endogenously derived compound, is a key mediator providing regulation of the complement system. In this study, the protective role of C1-INH was investigated in the setting of myocardial ischemia reperfusion injury. Guinea pig hearts (n = 20) were studied in control (n = 10) and ...
Olivecrona, Göran
Introduction: The mechanism of post ischemic reactive hyperemia is still unknown but now thought to be multifactorial and perhaps involving purinergic signalling. Purines such as ATP and ADP have recently been discovered to play a vital role in the regulation of vascular tone. We postulated that ADP could play a ...
Hicks Juan J - - 2007
In myocardial infarctions with ST-segment elevation, ischemia followed by reperfusion (IR) leads to arrhythmia, myocardial stunning and endothelial dysfunction injury by reactive oxygen species (ROS). To determine the impact of ROS, we examined the effect of antioxidant vitamins on biochemical changes and arrhythmias induced by reperfusion before and after therapeutic ...
Selimoglu Ozer - - 2007
BACKGROUND: The prevention of perioperative ischemia-reperfusion injury is of critical importance, and this issue becomes more important in patients undergoing an early emergent revascularization procedure after an acute myocardial infarction. In this study, we sought to test the hypothesis that our simplified pressure-controlled initial reperfusion technique would be protective against ...
Otake Hiromasa - - 2007
OBJECTIVES: This study evaluated the efficacy of catheter-based transcoronary myocardial hypothermia (CTMH) in pigs with acute myocardial ischemia. BACKGROUND: Although it has been suggested that hypothermia therapy can attenuate myocardial necrosis, few applications have been accepted for clinical use. METHODS: This study comprises 2 substudies. In both studies, pigs underwent ...
Schmidt M R - - 2007
Remote ischemic preconditioning reduces myocardial infarction (MI) in animal models. We tested the hypothesis that the systemic protection thus induced is effective when ischemic preconditioning is administered during ischemia (PerC) and before reperfusion and examined the role of the K(+)-dependent ATP (K(ATP)) channel. Twenty 20-kg pigs were randomized (10 in ...
Gale Stephen C - - 2007
BACKGROUND: In cardiopulmonary bypass, extracorporeal circulation activates neutrophils, which contribute to ischemia reperfusion injury and postoperative myocardial dysfunction. Perfluorocarbons (PFCs) are compounds that dissolve oxygen and have anti-inflammatory and neutrophil-stabilizing properties. We hypothesized that perflubron emulsion (PFE), a PFC, would attenuate neutrophil activation during simulated extracorporeal circulation (SECC) and would ...
Lu Chuanjiang - - 2006
BACKGROUND: Nicorandil has been reported to induce cardioprotection by opening the mitochondrial K(ATP) channels. However, whether nicorandil affects reactive oxygen species is unclear. METHODS AND RESULTS: The hearts of male Sprague-Dawley rats were excised and perfused on a Langendorff apparatus with Krebs-Henseleit solution with a gas mixture of 95% O(2) ...
Hale Sharon L - - 2006
Ranolazine is a selective inhibitor of the late sodium current relative to peak sodium channel current, and via this mechanism, it may decrease sodium-dependent intracellular calcium overload during ischemia and reperfusion. Ranolazine reduces the frequency of angina attacks, but there is little information on its effects on myocardial stunning after ...
Besse S - - 2006
Cardiovascular ageing is associated with an increase in cardiac susceptibility to ischaemia and reperfusion and production of reactive oxygen species has been suspected to be responsible for this age-associated particular vulnerability. To determine whether administration of antioxidant treatment could afford some protection against ischaemia and reperfusion during aging, isolated perfused ...
Penumathsa Suresh Varma - - 2007
Therapeutic angiogenesis represents a novel approach for the prevention and treatment of ischemic heart disease. This study examined a novel method of stimulating myocardial angiogenesis using secoisolariciresinol diglucoside (SDG), a plant lignan isolated from flaxseed. SDG has been shown to decrease serum cholesterol and reduce the extent of atherosclerosis. In ...
Manintveld Olivier C - - 2007
Postconditioning (POC) is known as the phenomenon whereby brief intermittent ischemia applied at the onset of reperfusion following index ischemia limits myocardial infarct size. Whereas there is evidence that the algorithm of the POC stimulus is an important determinant of the protective efficacy, the importance of the duration of index ...
Laguens Rubén P - - 2007
We have recently reported that in chronic myocardial ischemia, adult mammalian cardiomyocytes express P-glycoprotein (P-gp). We now investigate if P-gp is also expressed in acute regional ischemia followed by reperfusion. Adult conscious sheep underwent 12-min occlusion of the mid-left anterior descending artery (inflatable cuff). Successful ischemia-reperfusion was confirmed by monitoring ...
Jormalainen M - - 2007
BACKGROUND: Antithrombin (AT) may alleviate many cardiopulmonary bypass (CPB) and ischemia-reperfusion (I/R)-related adverse effects. Using a porcine model of clinical cardiac surgery on CPB, we tested the effects of supplementary AT on myocardial and lung I/R injury. METHODS: Twenty pigs undergoing 60-min aortic clamping and 75-min normothermic perfusion were randomized ...
Støttrup Nicolaj B - - 2006
1. L-Glutamate and glutamine have been suggested to have cardioprotective effects. However, the issue is controversial and the metabolic mechanisms underlying a beneficial effect are not well understood. 2. In the present study we investigated the effects of L-glutamate and glutamine on haemodynamic recovery, the rate of de novo glycogen ...
Metzsch C - - 2007
BACKGROUND: Inotropic and myocardial anti-ischemic effects have been demonstrated with levosimendan. The comparison of levosimendan started before an ischemia-reperfusion event as compared with levosimendan started during ischemia has not been studied. METHODS: In anesthetized pigs, a major branch of the circumflex artery was completely occluded for 30 min and then ...
Onogi Hirohito - - 2006
1. In the present study, we investigated the effect of 3-methyl-1-phenyl-2-pyrazolin-5-one (edaravone), a free radical scavenger, on myocardial infarct (MI) size and cardiac function in an in vivo model of MI in rabbits. We further investigated the contribution of hydroxyl radicals, superoxide and nitric oxide (NO) to its effects. 2. ...
Richardt Doreen - - 2006
During myocardial ischemia, a substantial accumulation of norepinephrine occurs in the ischemic zone due to a local nonexocytotic release of norepinephrine. Norepinephrine release is driven by the neuronal monoamine transporter (NET), which reverses its usual transmembrane transport direction. We investigated whether this local accumulation of norepinephrine contributes to irreversible myocardial ...
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