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Halkos Michael E - - 2004
BACKGROUND: Ischemic preconditioning (IPC) has been used in off-pump coronary artery bypass surgery (OPCAB) to reduce potential injury secondary to ligation of the target vessel. Previous studies have shown that a brief period of repetitive coronary occlusion applied at the onset of reperfusion, postconditioning (postcon), attenuates myocardial injury. This study ...
Fitzpatrick Colleen M - - 2005
Hypoxia from birth increases resistance to myocardial ischemia in infant rabbits. We hypothesized that increased cardioprotection in hearts chronically hypoxic from birth persists following development in a normoxic environment and involves increased activation of nitric oxide synthase (NOS) and ATP-dependent K (K(ATP)) channels. Resistance to myocardial ischemia was determined in ...
Andreadou Ioanna - - 2004
Free radicals are involved in the protective mechanism of preconditioning (PC), whereas antioxidant compounds abolish this benefit. Melatonin is a hormone with antioxidant properties. The aim of our study was to evaluate the effect of melatonin on infarct size in ischemic preconditioning in vivo. We randomly divided 33 male rabbits ...
Brühl Annette - - 2004
The release of choline as a water-soluble product of phospholipid hydrolysis was measured in the perfusate of rat hearts to monitor ischemic membrane degradation and its protection by ischemic preconditioning (IPC). Hearts were subjected to global ischemia (GI; 30 min of no-flow) followed by 60 min of reperfusion. To induce ...
Chen Hong - - 2004
BACKGROUND: Recent evidence suggests that chloride channels may be involved in ischemic preconditioning (IPC). In this study, we tested whether the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels, which are expressed in the heart and activated by protein kinase A and protein kinase C, are important for IPC in ...
Huang Cheng-Hsiung - - 2004
BACKGROUND: Several nonischemic stimuli have been shown to precondition myocardium. We investigated cardioprotective effects and underlying mechanisms of brief pressure overload of the left ventricle in this study. METHODS: Brief pressure overload of the left ventricle was achieved by two 10-minute partial snaring of the ascending aorta so that systolic ...
Colantonio David A - - 2004
OBJECTIVE: Degradation of cardiac troponin I (cTnI) has been proposed to represent the underlying molecular mechanism responsible for post-ischemic contractile dysfunction of viable but 'stunned' myocardium. However, this concept is largely derived from models of brief, sublethal ischemia essentially devoid of necrosis, and there is speculation that defects in cTnI ...
Skyschally Andreas - - 2004
OBJECTIVE: After coronary microembolization (ME) adenosine is released from ischemic areas of the microembolized myocardium. This adenosine dilates vessels in adjacent nonembolized myocardium and increases coronary blood flow. For ischemic preconditioning (IP) to protect the myocardium against infarction, an increase in the interstitial adenosine concentration (iADO) prior to the subsequent ...
Zhang Qihang - - 2004
We tested the hypothesis that myocardial stunning would be reduced by increased cyclic GMP and cGMP protein kinase activity. Hearts were instrumented in eight open-chest anesthetized dogs. The left anterior descending coronary artery (LAD) was occluded for 15 minutes followed by a 30-minute recovery and infusion of 8-Bromo-cGMP (0.1 and ...
Bolli Roberto - - 2004
Over the past 30 years, hundreds of experimental interventions (both pharmacologic and nonpharmacologic) have been reported to protect the ischemic myocardium in experimental animals; however, with the exception of early reperfusion, none has been translated into clinical practice. The National Heart, Lung, and Blood Institute convened a working group to ...
Valtchanova-Matchouganska A - - 2004
For the first time the involvement of C-Reactive protein (CRP) in early (acute) and delayed ischemic (IPC) and pharmacological (chemical) preconditioning (CPC) in an in vivo model of rat myocardial infarction was presented. Acute IPC was produced by three 5 minute occlusion (ischemia) periods interspersed with 5 minute reperfusion, followed ...
Dickson Eric W - - 2004
BACKGROUND: Intermittent brief "preconditioning" (PC) ischemia has been shown to render the heart resistant to a subsequent sustained ischemic insult, in part through an opioid-dependent mechanism. Using the rabbit model, we tested the hypothesis that intermittent in vivo apnea elicits a cardioprotective response similar to that achieved with conventional PC ...
Gamperl A Kurt - - 2004
Fish cardiac physiology and anatomy show a multiplicity of intraspecific modifications when exposed to prolonged changes in environmentally relevant parameters such as temperature, hypoxia and food availability, and when meeting the increased demands associated with training/increased activity and sexual maturation. Further, there is evidence that rearing fish under intensive aquaculture ...
Beresewicz Andrzej - - 2004
OBJECTIVES: A hypothesis was tested that a reaction product between superoxide (O2-) and nitric oxide (NO) mediates post-ischemic coronary endothelial dysfunction that ischemic preconditioning (IPC) protects the endothelium by preventing post-ischemic cardiac O2- and/or NO formation, and that the opening of the mitochondrial ATP-dependent potassium channel (mKATP) plays a role ...
Gamperl A Kurt - - 2004
Research has shown that the trout heart is normally hypoxia-sensitive, and that it can be preconditioned. However, we have identified a group of rainbow trout Oncorhynchus mykiss that shows a surprising degree of myocardial hypoxia tolerance. In this study, we used in situ hearts from these fish as a comparative ...
Ogita Hisakazu - - 2004
The purpose of this study is to examine whether raloxifene, one of the selective estrogen receptor modulators, could improve myocardial ischemia and to assess the mechanisms involved. In open-chest beagle dogs anesthetized by intravenous infusion of sodium pentobarbital, the left anterior descending coronary artery (LAD) was perfused from the left ...
Samarkandi A H AH Dept. of Anaesthesia, Faculty of Medicine, King Saud University; Riyadh, Saudi Arabia. - - 2004
Twenty ASA III and IV adult patients scheduled for elective coronary artery surgery were included in the study. Anesthesia was induced and maintained with either sevoflurane (sevoflurane group; n = 10) or propofol (propofol group; n = 10). All preoperative cardiac medications were continued until the morning of surgery. There ...
Wang Sheng - - 2004
1 The antioxidant properties of flavonols in vivo and their potential benefits in myocardial ischaemia/reperfusion (I/R) injury have been little investigated. We evaluated the ability of a synthetic flavonol, 3',4'-dihydroxyflavonol (DiOHF) to scavenge superoxide in post-I/R myocardium and to prevent myocardial I/R injury. 2 Anaesthetized sheep were studied in four ...
Kristensen Jens - - 2004
OBJECTIVE: Reliable methods for assessment of tissue reperfusion early after revascularizing therapy for acute myocardial infarction are needed. Myocardial perfusion imaging with Tc sestamibi (MIBI MPI) may serve this purpose. Usage during early reperfusion may be problematic e.g. due to ischaemic preconditioning (IP), which is important in inducing ischaemic tolerance. ...
Riess Matthias L - - 2004
A steadily increasing number of investigations demonstrate that preconditioning with volatile anesthetics attenuates the deleterious effects of myocardial ischemia and reperfusion injury by an ischemic preconditioning-like mechanism. Thus volatile anesthetics may represent the best choice for anesthesia of patients at risk for myocardial ischemia. However, factors such as old age, ...
Carr-White Gerald - - 2004
OBJECTIVES: Many patients with coronary artery disease demonstrate chronic resting ischaemic myocardial dysfunction. We have investigated whether this ischaemia influences the myocardial damage caused by the period of coronary occlusion involved in beating heart surgery. METHODS: Thirty-three patients with chronic stable angina and normal left ventricular ejection fraction were studied. ...
Schulz Rainer - - 2004
Connexin 43 (Cx43) is the essential protein to form hemichannels and gap junctions in the myocardium. The phosphorylation status of Cx43 which is regulated by a variety of protein kinases and phosphatases determines hemichannel and/or gap junction conductance and permeability. Gap junctions are involved in cell-cell coupling while hemichannels contribute ...
Cui Jianhua - - 2004
BACKGROUND: A recent study showed increased myocardial content of ceramide and sphingosine during preconditioning (PC). Because sphingosine-1-phosphate, a metabolite of ceramide, may function as an antiapoptotic factor, we hypothesized the increased ceramide during PC may be heart's effort to harness its own protection. STUDY DESIGN: The isolated hearts were divided ...
Rakotovao Andry - - 2004
It is now well established that oxidative stress resulting from reactive oxygen species (ROS) that are generated in cardiac myocytes subjected to ischemia/reperfusion plays a causative role in the development of heart failure and may contribute to promote cell death. During the last decade, several groups have reported that, in ...
Pagel Paul S - - 2004
Recent evidence suggests that chronic ingestion of small quantities of ethanol may protect myocardium from ischemic injury by activating many of the endogenous signal transduction elements that have been implicated during other forms of preconditioning. Studies conducted in a variety of animal models in vitro and in vivo have indicated ...
Juhasz Bela - - 2004
We studied the effects of various cycles of preconditioning (PC) (one cycle, 1 x PC; two cycles, 2 x PC; three cycles, 3 x PC; and four cycles, 4 x PC) on cardiac function, infarct size, and the incidence of reperfusion-induced arrhythmias in isolated hearts obtained from rabbits with hypercholesterolemia. ...
Benter Ibrahim F - - 2004
The signaling pathways involved in ischemic heart disease are not well characterized. In this study, the roles of Ras-GTPase, tyrosine kinases (TKs) and Ca2+/calmodulin-dependent protein kinase II (CaMKII) in global ischemia and reperfusion (I/R) in a perfused rat heart model were investigated and compared to beneficial effects produced by preconditioning ...
Lindhardt T B - - 2004
BACKGROUND: Repeated episodes of myocardial ischaemia may lead to ischaemic preconditioning. This is believed to be mediated by the ATP sensitive potassium channels. OBJECTIVE: To examine the effect of pharmacological modulation of the ATP sensitive potassium channels during repeated coronary occlusions. DESIGN: Double blind, double dummy study. METHODS: 38 patients ...
Krenz Maike - - 2004
Epidemiological data suggest that a cardioprotective effect of acute alcohol exposure exists in humans. Recent studies in animal models indicate that transient alcohol exposure can indeed reduce myocardial infarct size and exert a preconditioning-like protective effect akin to ischemic preconditioning (IPC). Moreover, the mechanism of alcohol-induced cardioprotection in part resembles ...
Das Dipak K - - 2004
Thioredoxins are a class of small redox-regulating proteins that appear to play a crucial role in many oxidative stress-inducible degenerative diseases. A recent study demonstrated a reduction of thioredoxin-1 (Trx1) protein in the ischemic reperfused myocardium. When the same heart was adapted to ischemic stress by preconditioning with repeated cyclic ...
Qin Qining - - 2004
Exogenous nitric oxide (NO) triggers a preconditioning-like effect in heart via a pathway that is dependent on reactive oxygen species. This study examined the signaling pathway by which the NO donor S-nitroso-N-acetylpenicillamine (SNAP, 2 microM) triggers its anti-infarct effect. Isolated rabbit hearts experienced 30 min of regional ischemia and 120 ...
Overgaard Johannes - - 2004
In many vertebrates, a short episode of oxygen lack protects against myocardial necrosis during a subsequent, longer period of oxygen deprivation. This protective effect, termed preconditioning, also improves the functional recovery. Improved functional recovery has been reported for hypoxia-sensitive, in situ perfused rainbow trout hearts, but appears absent in another ...
Ebel Dirk - - 2004
BACKGROUND: Short administration of volatile anesthetics preconditions myocardium and protects the heart against the consequences of subsequent ischemia. Activation of tyrosine kinase is implicated in ischemic preconditioning. The authors investigated whether desflurane-induced preconditioning depends on activation of tyrosine kinase. METHODS: Sixty-four rabbits were instrumented for measurement of left ventricular pressure, ...
Riess Matthias L - - 2004
BACKGROUND: Anesthetic preconditioning (APC) with sevoflurane reduces myocardial ischemia-reperfusion injury. The authors tested whether two brief exposures to sevoflurane would lead to a better preconditioning state than would a single longer exposure and whether dual exposure to a lower (L) concentration of sevoflurane would achieve an outcome similar to that ...
Tsai Ben M - - 2004
Preconditioning describes the phenomenon by which a traumatic or stressful stimulus confers protection against subsequent injury. Originally recognized in dog heart subjected to ischemic challenges, preconditioning has been demonstrated in multiple species, can be induced by various stimuli, and is applicable in different organ systems. Tremendous progress has been made ...
Lee Byeong Han - - 2004
The aim of this study was to characterize the effect of increasing numbers of preconditioning cycles on the different branching patterns (bifurcation/trifurcation) of the coronary artery in the rabbit heart. Fifty-six NZW rabbits were assigned to a bifurcation group and subjected to 0, 1, 3, 5, or 7 (B0, B1, ...
Alcindor Dunbar - - 2004
BACKGROUND: Cyclooxygenase-2 (COX-2) mediates the late phase of ischemic preconditioning (IPC), but whether this enzyme modulates early IPC, anesthetic-induced preconditioning (APC), or other forms of pharmacologic preconditioning (PPC) is unknown. The authors tested the hypothesis that COX-2 is an essential mediator of IPC, APC, and PPC in vivo. METHODS: Barbiturate-anesthetized ...
Tanaka Katsuya - - 2004
BACKGROUND: Whether volatile anesthetics produce a second window of preconditioning is unclear. The authors tested the hypothesis that isoflurane causes delayed preconditioning against infarction and, further, that cyclooxygenase (COX)-2 mediates this beneficial effect. METHODS: Rabbits (n = 43) were randomly assigned to receive 0.9% intravenous saline, the selective COX-2 inhibitor ...
Ebrahim Z Z The Hatter Institute, UCL Hospitals and Medical School, London, - - 2004
Bradykinin is an important endogenous trigger of myocardial ischemic preconditioning (IPC). Through simultaneous inhibition of neutral endopeptidase and angiotensin converting enzyme, omapatrilat prevents enzymatic degradation of bradykinin. The aim of this study was to investigate if omapatrilat, through its ability to augment bradykinin levels, can augment a subthreshold IPC stimulus ...
Loubani Mahmoud - - 2004
OBJECTIVE: Ischemic preconditioning confers cardioprotection in early and delayed phases. We investigated the delayed window of pharmacological and ischemic preconditioning in human myocardium, and the involvement of mitoKATP, PKC and p38MAPK. METHODS: These studies were carried out using human right atrial tissue in a cell necrosis model. The tissue was ...
Weinbrenner Christof - - 2004
BACKGROUND: Ischemic preconditioning (PC) is a powerful mechanism in reducing infarct size of the heart. Protection can be performed either by an ischemic stimulus of the heart itself or by ischemia of an organ distant to the heart (remote PC). We have previously shown that remote PC by infrarenal occlusion ...
Krieg T - - 2004
In ischemic preconditioning (IPC) a brief ischemic period protects the heart from a subsequent ischemic insult by an unknown mechanism. Osmotic swelling has been proposed to be a major cause of cell death when ischemic tissue is reperfused. The present study tests whether the preconditioned heart during reperfusion might release ...
Eisen Alon - - 2004
The phenomenon of "ischemic preconditioning" has been recognized for almost two decades. In experimental animals and humans, a brief period of ischemia has been shown to protect the heart from more prolonged episodes of ischemia, and reduce the degree of impaired ventricular function or subsequent damage. Ischemic preconditioning is classified ...
De Hert Stefan G - - 2004
PURPOSE OF REVIEW: Increasing experimental evidence is indicating that volatile anesthetic agents may exert direct cardioprotective effects. They have been shown to directly precondition or indirectly enhance ischemic preconditioning. This results in protection against reversible and irreversible ischemic myocardial damage. In addition, volatile anesthetics also decrease the extent of the ...
Kolár F - - 2004
Effective protection of the heart against ischemia/reperfusion injury is one of the most important goals of experimental and clinical research in cardiology. Besides ischemic preconditioning as a powerful temporal protective phenomenon, adaptation to chronic hypoxia also increases cardiac tolerance to all major deleterious consequences of acute oxygen deprivation such as ...
Dos Santos Pierre - - 2004
The aim of the works presented here is to analyze the alterations induced by acute ischemia-reperfusion and chronic ischemia on mitochondrial function, in relation to alterations on heart function. Parameters of mitochondrial function were assessed on skinned fibers coming from isolated perfused rat hearts. The effects of chronic ischemia were ...
Fujita Masanori - - 2004
INTRODUCTION: When establishing a myocardial infarction model in rabbits, artificial ventilation under endotracheal intubation is required to prevent pulmonary collapse caused by pneumothorax. However, it is difficult to carry out endotracheal intubation due to the rabbit anatomy. We therefore attempted to develop a myocardial infarction model in rabbits without endotracheal ...
Jancso G - - 2004
To show that angiotensin-converting enzyme (ACE) inhibition potentiates subthreshold ischemic preconditioning (IPC) via the elevation of bradykinin activity, leading to a fully delayed cardioprotective response. On day 1 of the experiment, pigs were subjected to sham (group 1, controls) or IPC protocols. In groups 2 and 3, 4x5 min and ...
Szekeres László - - 2004
In 1983, a delayed and prolonged cardioprotection induced by drugs was described. This pharmacologically induced adaptation to stress represents a new trend in cardioprotection as opposed to the classical drug treatment that was based on the presence of drug-receptor binding. Such a long-lasting, delayed adaptation can be induced by non-injurious ...
Meier J J - - 2004
In the UGDP study, published in the 1970s, a high incidence of cardiovascular mortality was found in patients treated with the sulfonylurea agent tolbutamide. Impaired ischaemic preconditioning is presumed to be the most important mechanism for the excess cardiovascular mortality observed. However, as tolbutamide has only a low affinity for ...
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