Ischemic preconditioning activates prosurvival kinases and reduces XXXX .

@entity296 @entity5721 @entity1976 @entity63 @entity39 @entity2310 @entity2508 @entity5 @entity4124 @entity1977 @entity741 @entity35 @entity583
BACKGROUND: Ischemic preconditioning has been reported to protect the myocardium against @entity63 and @entity5721 . The underlying mechanisms have been extensively investigated but are not fully elucidated. In this study, we investigated the role of apoptosis in ischemic preconditioning protection and the signal pathways involved. METHODS: @entity741 and reperfusion were induced in anesthetized male @entity35 by a 40-minute occlusion and a 3-hour reperfusion of the left anterior descending coronary artery. Ischemic preconditioning was elicited by two 10-minute coronary artery occlusions and two 10-minute reperfusions. RESULTS: The @entity583 size, expressed as the percentage of area at risk, was significantly decreased in the ischemic preconditioning group (16.8      2.0% and 27.9      2.7% in the @entity63 and reperfusion groups, respectively, p  <  0.001). Additionally, ischemic preconditioning significantly reduced apoptosis, as evidenced by the decrease in the terminal deoxynucleotidyl transferase-mediated @entity1977 nick-end labeling-positive nuclei, DNA laddering, and @entity4124 activation. Western blot analysis revealed that ischemic preconditioning significantly reduced @entity296 @entity39 factor-a levels. @entity1976 was increased, whereas @entity2310 was decreased in the myocardium. Phosphorylation of the prosurvival kinases, including Akt and @entity2508 , was significantly increased. Hemodynamics, area at risk, and mortality did not differ significantly among the groups. CONCLUSION: Ischemic preconditioning reduces apoptosis induced by @entity741 and reperfusion. The underlying mechanisms might be related to inhibition of both the extrinsic and the intrinsic apoptotic pathway via inhibition of production of @entity5 @entity39 factor-a, modulation of expression of @entity1976 and @entity2310 , and activation of the prosurvival kinases.
