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Depressed Ca2+ Activation of Contraction as a Consequence of Reperfusion-induced Cellular Calcium Overload in Ferret Hearts
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In this article, the authors measured developed pressure (DP) at several [Cal6 (0.5-7.5 mM) in isovolumic Langendoriperfused ferret hearts at 370C after 15 min of global ischemia (stunned group, n = 13) or in a nomnschemic control group (a = 6).Abstract:
Contractile dysfunction in stunned myocardium could result from a decrease in the intracellular free [Ca2+1 transient during each beat, a decrease in maximal Ca2+-activated force, or a shift in myofilament Ca2+ sensitivity. We measured developed pressure (DP) at several [Cal6 (0.5-7.5 mM) in isovolumic Langendoriperfused ferret hearts at 370C after 15 min of global ischemia (stunned group, n = 13) or in a nomnschemic control group (a = 6). At all ICal6, DP was depressed in the stunned group (P 0.05), and higher than in the stunned group (P < 0.05). Myocardial IATP] observed by phosphorusNMR failed to correlate with functional recovery. In conclusion, contractile dysfunction in stunned myocardium is due to a decline in maximal force, and a shift in Cao sensitivity (which may reflect either decreased myofilament Ca2+ sensitivity or a decrease in the [Ca2+j transient). Our results also indicate that calcium entry upon reperfusion plays a major role in the pathogenesis of myocardial stunning.read more
Citations
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Molecular and Cellular Mechanisms of Myocardial Stunning
Roberto Bolli,Eduardo Marbán +1 more
TL;DR: An important implication of the phenomenon of myocardial stunning is that so-called chronic hibernation may in fact be the result of repetitive episodes of stunning, which have a cumulative effect and cause protracted postischemic dysfunction.
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Mechanism of myocardial "stunning".
TL;DR: The concepts discussed in this review should provide not only a conceptual framework for further investigation of the pathophysiology of reversible ischemia-reperfusion injury but also a rationale for developing clinically applicable interventions designed to prevent postischemic ventricular dysfunction.
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Interaction of Cardiovascular Risk Factors with Myocardial Ischemia/Reperfusion Injury, Preconditioning, and Postconditioning
TL;DR: The aim of this review is to show the potential for developing cardioprotective drugs on the basis of endogenousCardioprotection by pre- and postconditioning and to review the evidence that comorbidities and aging accompanying coronary disease modify responses to ischemia/reperfusion and the cardiop Rotection conferred by preconditioning and post conditioning.
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Marked reduction of free radical generation and contractile dysfunction by antioxidant therapy begun at the time of reperfusion. Evidence that myocardial "stunning" is a manifestation of reperfusion injury.
TL;DR: It is demonstrated that a substantial portion of the damage responsible for myocardial stunning develops in the initial seconds of reperfusion and can be prevented by antioxidant therapy started just before reftow, providing direct evidence for a causal role of reactive oxygen species.
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Reperfusion injury and its pharmacologic modification.
TL;DR: From the therapeutic point of view, the divergent results of experimental interventions and the possibility that the abrupt onset of reperfusion in animals differs from the situation in humans with thrombolysis means that the best way currently available to limit reperFusion injury is by minimizing the ischemic period by early reperfusions and by optimizing the metabolic status of the isChemic myocardium at the end of theIschemicperiod.
References
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Book
Statistical Principles in Experimental Design
TL;DR: In this article, the authors introduce the principles of estimation and inference: means and variance, means and variations, and means and variance of estimators and inferors, and the analysis of factorial experiments having repeated measures on the same element.
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Statistical Principles in Experimental Design
TL;DR: This chapter discusses design and analysis of single-Factor Experiments: Completely Randomized Design and Factorial Experiments in which Some of the Interactions are Confounded.
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The stunned myocardium: prolonged, postischemic ventricular dysfunction.
TL;DR: If prolonged, chronic postischemic left ventricular dysfunction can progress to myocardial scarring and ischemic cardiomyopathy, it may be important to determine how often it can be ameliorated by permanent improvement of myocardia perfusion by surgical treatment.
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