Protocol 1—Normoglycemic C57BL/6J mice. (A) Infarct size (expressed as a percentage of the total LV). *p < 0.05 versus Control. (B) Original immunoblots of phospho-ERK, p70S6 kinase, and glycogen synthase kinase–3β in sham, control, and PostC hearts. (C) Cardiac expression of phospho-ERK, assessed by immunoblotting. *p < 0.05 versus Control; †p < 0.05 versus Sham. (D) Cardiac concentration of phospho-ERK, quantified by EIA. EIA, enzyme immunometric assay; ERK, extracellular-signal regulated kinase; LV, left ventricle; PostC, postconditioned.