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Forman Mervyn B - - 2007
High risk ST segment elevation myocardial infarction (STEMI) patients undergoing reperfusion therapy continue to exhibit significant morbidity and mortality due in part to myocardial reperfusion injury. Importantly, preclinical studies demonstrate that progressive microcirculatory failure (the "no-reflow" phenomenon) contributes significantly to myocardial reperfusion injury. Diagnostic techniques to measure tissue perfusion have ...
Juhasz Bela - - 2007
The aim of our study was to investigate the contribution of the adrenocorticotropic hormone fragment, ACTH (4-10), on the recovery of postischemic cardiac function. Effects of ACTH (4-10) on caspase-3 activity, cardiomyocyte and endothelial apoptosis, and HO-1 protein expression were studied. Rats were treated with various doses of ACTH (4-10), ...
Sakamoto Hiroaki - - 2007
Reperfusion therapy for myocardial infarction is currently the most effective means for limiting early and late mortality. We sought to elucidate how reperfusion influences remodeling strains in the infarct, borderzone, and remote myocardial regions. Understanding the effects of reperfusion on regional remodeling will help to evaluate and optimize emerging treatments ...
MacDonald Ashley C - - 2008
Effects of the Na(+)-Ca(2+) exchange (NCX) inhibitor KB-R7943 on electrical and contractile function were examined in guinea pig ventricular myocytes exposed to ischemia and reperfusion. Action potentials and transmembrane currents were recorded with microelectrodes; contractions were measured with an edge detector. Cells were exposed to simulated ischemia (hypoxia, hypercapnia, hyperkalemia, ...
Kleinz Matthias J - - 2008
Apelin, the endogenous ligand of the G protein-coupled APJ receptor, is a peptide mediator with emerging regulatory actions in the heart. The aim of the present studies was to explore potential roles of the apelin/APJ system in myocardial ischaemia/reperfusion injury. To determine the cardiac expression of apelin/APJ and potential regulation ...
Lee An-Sheng - - 2008
Quinazoline-based compounds such as prazosin and its congeners including doxazosin, bunazosin, and terazosin are widely used as antihypertensive agents. However, there were many clinical observations showing that using these agents may result in higher risk of cardiovascular accidents in recent years. In this study, we compared the effects of four ...
Hadzimichalis Norell M - - 2007
Our laboratory has previously reported that acetaminophen confers functional cardioprotection following cardiac insult, including ischemia/reperfusion, hypoxia/reoxygenation, and exogenous peroxynitrite administration. In the present study, we further examined the mechanism of acetaminophen-mediated cardioprotection following ischemia/reperfusion injury. Langendorff-perfused guinea pig hearts were exposed to acute treatment with acetaminophen (0.35 mM) or vehicle ...
Høyer Christian - - 2007
BACKGROUND: Warm ischemia and subsequent reperfusion of the heart can induce a temporary dysfunction known as myocardial stunning. The aim of this study was to investigate the ability of tissue Doppler imaging (TDI) to quantify longitudinal myocardial stunning close to the apex, and perform a comparison with sonomicrometry using a ...
Nie Ruqiong - - 2007
Oxidative stress may play a causative role in myocardial ischemia-reperfusion injury. However, it is a relatively understudied aspect regarding an optimal timing of antioxidant intervention during ischemia-reperfusion. The present study investigates the effect of different treatment regimens of Salvia miltiorrhiza (SM) herb extracts containing phenolic compounds that possess potent antioxidant ...
Yang Xin-Chun - - 2007
BACKGROUND: Postconditioning has been shown to reduce infarct size during reperfusion (< 72 hours). However, it is unknown whether the infarct size reduction with postconditioning is a long-term effect after clinical percutaneous coronary intervention (PCI). The present study tested the hypothesis that postconditioning during primary PCI preserves global cardiac function ...
Baker John E - - 2008
Thrombopoietin (Tpo) is known for its ability to stimulate platelet production. However, it is currently unknown whether Tpo plays a physiological function in the heart. We assessed the potential protective role of Tpo in vitro and in vivo in two rat models of myocardial ischaemia/reperfusion. Tpo receptor (c-mpl) message was ...
Ley James J JJ Department of Neurology, University of Miami, Miller School of Medicine, Miami, FL 33101, United - - 2008
Protecting the myocardium from ischemia-reperfusion injury has significant potential to reduce the complications of myocardial infarction and interventional revascularization procedures. Reperfusion damage is thought to result, in part, from oxidative stress. Here we use a novel method of percutaneous coronary occlusion to show that the potent antioxidant and neuroprotective free-radical ...
Audi Said - - 2007
OBJECTIVE: It was recently demonstrated that the radiolabeled C2A domain of synaptotagmin I accumulates avidly in the area at risk after ischemia and reperfusion. The objective was to quantitatively characterize the dynamic uptake of radiolabeled C2A in normal and ischemically injured myocardia using a compartmental model. METHODS: To induce acute ...
Tissier R - - 2007
Patients currently treated for acute myocardial infarction receive reperfusion therapy as their only anti-infarct intervention. Although pharmacologic agents have been evaluated in the past for their ability to salvage ischemic myocardium when administered at reperfusion, until very recently none has demonstrated clear efficacy in clinical trials. However, a new generation ...
Nilsson Johan B - - 2008
BACKGROUND: The fibrinolytic system and von Willebrand factor (vWF) have been shown to play a role as risk factors for myocardial infarction. We performed this prospective cohort study to determine if components in the fibrinolytic system or vWF before or during treatment of AMI with streptokinase (SK) could predict reperfusion, ...
Streb Witold - - 2008
AIM: The study aim was to determine the sequence of changes in both wall thickness and function in 'at risk' myocardium (using M-mode and radial strain/strain-rate imaging) induced by reperfusion of an acute transmural infarction, and to relate these changes to the presence or absence of a pressure-limiting stenosis in ...
Brendt Peter - - 2008
AIM OF THE STUDY: Levosimendan, a calcium sensitiser, and cariporide, a blocker of the Na+/H+ exchanger, decrease necrosis and improve function following myocardial ischaemia. However, their role in myocardial stunning is unclear. We tested the hypothesis that levosimendan, cariporide, or their combination reduce stunning after global myocardial ischaemia. METHODS: In ...
Taki, Junichi
Background: To determine whether mild to moderate ischemia that is not severe enough to induce myocardial infarction will cause myocardial cell damage or apoptosis, the 99mTc-Annexin-V (Tc-A) uptake was studied in groups of rats with various intervals of coronary occlusion and reperfusion times. Methods and Results: After left coronary artery ...
Liu Xiaoshun - - 2007
OBJECTIVES: The purpose of this study was to test if nitric oxide (NO) could improve microvascular perfusion and decrease tissue injury in a porcine model of myocardial ischemia and reperfusion (I/R). BACKGROUND: Inhaled NO is a selective pulmonary vasodilator with biologic effects in remote vascular beds. METHODS: In 37 pigs, ...
Adameová Adriana - - 2007
The study was designed to characterise the influence of a novel acyl-CoA:cholesterol acyltransferase inhibitor, VULM 1457, on the severity of myocardial ischaemia-reperfusion injury in a model of diabetes mellitus and hypercholesterolaemia induced by co-administration of streptozotocin and a high fat-cholesterol diet. We used Langendorff-perfused rat hearts to measure the size ...
Zhao J-L - - 2007
It has been verified that nicorandil can attenuate myocardial no-reflow. However; the effects of nicorandil on endothelial junctions and Endothelin-1 (ET-1) are unknown. 40 mini-swines randomized into 5 study groups: 8 in control, 8 nicorandil pretreatment, 8 in glibenclamide (KATP channel blocker)-treated, 8 in nicorandil and glibenclamide-pretreated and 8 in ...
Bilir Ayten - - 2007
OBJECTIVES: The aim of the present study was to evaluate the effect of tramadol on isolated rat hearts subjected to global ischemia-reperfusion injury. DESIGN: Langerdorff perfused isolated rat hearts were subjected to 60 min of global ischemia following 60 min of reperfusion. In group I and III hearts were received ...
Das Biswadeep - - 2007
BACKGROUND: Endothelial ET(B) receptor activation by exogenously administered sarafotoxin 6c(a snake venom peptide with a sequence homology to ET-1 prior to ischemia activates release of nitric oxide(NO) and previous studies have shown that NO facilitates mitochondrial K(ATP) activation in cardiac cells and cardioprotection. OBJECTIVES AND METHODS: The aim of this ...
Eiferman Daniel - - 2007
BACKGROUND: Systemic infusion of glucose-insulin-potassium (GIK) is thought to confer myocardial protection during ischemia-reperfusion injury. Our laboratory has experience with real-time monitoring of glucose and pH levels using needle-mounted biosensors. We tested the hypothesis that GIK enhances myocardial metabolism as displayed by real-time myocardial metabolic monitoring. METHODS: A total of ...
Terrell Andrew M AM Department of Surgery, Indiana University School of Medicine, 545 Barnhill Drive, Emerson Hall 203, Indianapolis, IN 46202, - - 2008
Females demonstrate improved cardiac recovery after ischemia/reperfusion injury compared with males. Attenuation of myocardial dysfunction with preischemic estradiol suggests that estrogen may be an important mediator of this cardioprotection. However, it remains unclear whether post-injury estradiol may have clinical potential in the treatment of acute myocardial infarction. We hypothesize that ...
Bragadeesh T - - 2008
OBJECTIVE: To test the hypothesis that myocardial stunning is due to myofibrillar oedema. METHODS: Experiments were performed in anaesthetised closed-chest pigs. In 15 pigs (group 1), myocardial stunning was produced by repetitive ischaemia and reperfusion; 5 pigs each were studied at 2 hours, 2 days, and 5 days later. Circumferential ...
Wasilewski Jarosław - - 2007
INTRODUCTION: The no-reperfusion phenomenon occurs in a considerable number of patients despite restoration of the infarct-related artery (IRA) patency. Factors responsible for this phenomenon include myocardial structural changes, whereas haemorheological parameters that significantly contribute to microvascular resistance, have not been studied so far. AIM: To determine the possible relationship between ...
Taki Junichi - - 2007
BACKGROUND: To determine whether mild to moderate ischemia that is not severe enough to induce myocardial infarction will cause myocardial cell damage or apoptosis, the (99m)Tc-Annexin-V (Tc-A) uptake was studied in groups of rats with various intervals of coronary occlusion and reperfusion times. METHODS AND RESULTS: After left coronary artery ...
Xie J-R - - 2007
BACKGROUND: Recent evidence indicates that reperfusion of the heart after a period of ischemia leads to the opening of the mitochondrial permeability transition pore (MPTP). The aim of this study was to investigate cardioprotective effects of cyclosporine A (CsA), an inhibitor of the MPTP, in an in vivo model of ...
Wei Geng-Ze - - 2007
The pathogenesis of myocardial stunning caused by brief ischemia and reperfusion remains unclear. The aim of the present study was to investigate the underlying mechanism of myocardial stunning. An isolated cell model of myocardial stunning was firstly established in isolated rat ventricular myocytes exposed to 8 min of simulated ischemia ...
Bhuiyan Md Shenuarin - - 2007
VO(OPT), bis(1-oxy-2-pyridinethiolato)oxovanadium(IV), has been shown to increase tyrosine phosphorylation of proteins and promote the insulin receptor signaling, thereby elicit anti-diabetic action. We here investigated the cytoprotective action of VO(OPT) on myocardial infarction and cardiac functional recovery in rats subjected to myocardial ischemia/reperfusion and defined mechanisms underlying its cytoprotective action. Rats ...
Gomez Ludovic - - 2007
Inhibition of mitochondrial permeability transition pore (mPTP) opening by cyclosporin A or ischemic postconditioning attenuates lethal reperfusion injury. Its impact on major post-myocardial infarction events, including worsening of left ventricular (LV) function and death, remains unknown. We sought to determine whether pharmacological or postconditioning-induced inhibition of mPTP opening might improve ...
Zhu Xiaoguang - - 2007
The exposure of anionic phospholipids is a near-universal molecular signature for cell death. Based on our prior finding that the (99m)Tc-labeled C2A domain of synaptotagmin I accumulates intensely in the area at risk, this study quantitatively characterized the temporal and spatial distribution of the radiotracer in a rat model of ...
Dow Joan - - 2007
In our laboratory, postconditioning reliably reduces lethal ventricular arrhythmias in an in vivo rat model but its effect on necrosis in our model is unknown. In the present analysis, we tested a variety of postconditioning regimens in anesthetized rats subjected to 45 minutes of coronary occlusion and 120 minutes of ...
Oh Kwang-Seok - - 2007
The present study was performed to evaluate the cardioprotective effects of KR-33028, a novel Na+/H+ exchanger subtype 1 (NHE-1) inhibitor, in rat and dog models of coronary artery occlusion and reperfusion. In anesthetized rats subjected to a 45-min coronary occlusion and a 90-min reperfusion, KR-33028 at 5 min before occlusion ...
Takahashi Yosuke - - 2007
BACKGROUND: This study was designed to investigate whether administration of landiolol before or during ischemia protects the myocardium against ischemia-reperfusion (I/R) injury. METHODS: Isolated rat hearts were perfused with Krebs-Henseleit buffer using Langendorff apparatus. Cardiac arrest was achieved using St. Thomas' Hospital cardioplegic solution for 3 min. Each heart was ...
Kubitz Jens Christian - - 2007
Therapy for severe myocardial ischemia/reperfusion sometimes necessitates intermittent positive pressure ventilation, which may impair left ventricular function by reduction of ventricular loading. It is unknown today whether positive airway pressure also affects contractile force after myocardial ischemia/reperfusion. The authors tested whether positive end-expiratory pressure (PEEP) impairs myocardial contractility in acute ...
Baker John E - - 2007
Erythropoietin is known to stimulate red cell production and has recently been shown to protect the heart against injury from ischemia/reperfusion. However, it is unknown whether darbepoetin alfa (Dpa), a long-acting analog of erythropoietin, can play a protective role against myocardial infarction. We assessed the potential protective role of Dpa ...
Booth Erin A - - 2007
Previous studies have shown that estrogen treatment protects the heart from reperfusion injury. The adverse effects of long-term estrogen treatment limit its clinical use and emphasize the need for the development of specific pharmacological interventions such as pathway-selective estrogen receptor (ER) ligands. Pathway-selective ER ligands are compounds that retain estrogen's ...
Hausenloy Derek J - - 2007
Emerging studies suggest that signaling during the myocardial reperfusion phase contributes to ischemic preconditioning (IPC). Whether the activation of PKC, the opening of the mKATP channel, redox signaling and transient acidosis specifically at the time of myocardial reperfusion are required to mediate IPC-induced protection is not known. Langendorff-perfused rat hearts ...
Garcia Solange C - - 2007
BACKGROUND AND OBJECTIVE: Vascular endothelial cells play an important role in the control of vascular tone. The reasons for coronary endothelial dysfunction are complex and may involve ischemia/reperfusion injury. We investigated whether endothelial, smooth muscle, and myocardial dysfunction are independent phenomena. METHODS: Rabbit hearts were rapidly excised without intermittent ischemia, ...
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 ...
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