الفهرس 
Mechanism oflschemic Preconditioning............Only 14 pages are availabe for public view
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Abstract
Ischemic preconditioning refers to the ability of short periods of ischemia to make the myocardium more resistant to a subsequent ischemic insult (Tomai et al .,1999).
This term was introduced for the first time by Murry et al., (1986), who found in a canine model that,four consecutive periods of coronary occlusion of 5 minutes were able to reduce the infarct size caused by a subsequent period of occlusion of 40 minutes by as much as 75%. Therefore preconditioning was intially defined as a rapid adaptive response to brief ischemic insult;which slowed the rate of cell death during a subsequent prolonged period of ischemia .
Although the mechanisms underlying this adaptive response are incompletely defined,preconditioning has been verified in a number of animal models (Li et al.,1990).
Although the definition of ischemic preconditioning was intially used to describe reduction in myocardial necrosis by a brief episode of preceding ischemia ,the definition was extended to include protection against arrhythmia (Hagar et al., 1991) and postischemic left ventricular dysfunction (stunning) (Asimakis,1992 ).