Their landmark finding was that application of recombinant human (rh)EPO directly into the cerebral ventricles of gerbils prevented ischemia-induced learning disabilities and protected hippocampal pyramidal CA1 neurons from lethal ischemia while neutralization of the endogenous brain EPO by infusions of soluble EPOR before a nonlethal mild ischemia induced neuronal death [56]. Here, EPO is linked to ischemia.