MAPK3 and Cerebral ischemia: The current study revealed that administration of PGRN increased the level of phosphorylation of ERK1/2 and Akt induced by cerebral ischemia (Figure 7), suggesting that PGRN may promote ischemia‐induced hippocampal neurogenesis by activating the MAPK/ERK and PI3K/Akt signaling pathways.