The role of heat shock、ischemic preconditioning in the delayed protection of ischemic preconditioning

Objective: To observe the protective role of IP and HS on I/Rinjury. Methods:Wistar rats treated with prior whole-body hyperthermia(heat shock) and 24 hours recovery (n =11); or 3 episodes of 5 minutes of IP (ischemic preconditioning) and 24 hours of recovery( n =11);The control rats ( n =11)were sutured under coronary artery but not occluded. After 90 minutes of coronary artery occlusion and 3 hours of reperfusion ,the rats were killed and PKCa and PKCb were tested with immunohistochemical analysis.Results:Infarct size was significantly reduced in HS and IP group compared with control group(Ｐ0.01).Ventricular samples from all three groups showed no translocation of PKCa and PKCb from cytoplasm to membranes.Conclusion:In this model of I/R (ischemia/reperfusion),prior HS and IP were associated with significantly improved myocardial salvage after 90 minutes and 3 hours reperfusion.The PKCa and PKCb may not play an important role in conferring myocardial protection from I/R injury in this animal model.Further study for the mechanism of SWOP associated with IP was needed.