Fig. 3. Effect of remote preconditioning (RPC), nor-binaltorphimine (nor-BNI), U-50,488H, dynorphin, naltrindole, and atractyloside (Atr) on lactate dehydrogenase (LDH) levels in plasma. LDH levels in plasma at 10 min of reperfusion after 30 min myocardial ischemia in rats subjected to different treatments (see details in Material and Methods). n values are indicated on the columns. Values are mean ± SD. *P < 0.05 , **P < 0.01  versus I/R. ##  P < 0.01  versus RPC. δδ  P < 0.01  versus U-50,488H. I/R = ischemia–reperfusion; RPC = remote preconditioning.