GFRA1 and ischemia: We have previously shown a role for glutamate receptors in hippocampal neuronal death following oxygen and glucose deprivation (OGD), an in vitro model of transient global ischemia.1 Therefore, we compared the alterations in Ret51, Ret9 and GFRα1 protein levels in cultured hippocampal neurons subjected to OGD with those observed after excitotoxic stimulation.