GSK3B and ischemia reperfusion injury: Recently, Nishihara et al.[26] reported that administration of Epo with IPC produces additional cardioprotection in the rat heart against I/R-induced injury by enhancing the phosphorylation of GSK-3β and also that the relative importance of PKC and PI-3K pathways differs in the Epo-induced and IPC-induced cardioprotection against ischemia-reperfusion injury.