GAP43 and ischemia: Western blotting revealed that the protein expression of the GAP43 in the ischemic penumbra gradually increased after 2 h and 6 h of ischemia/reperfusion when compared with the sham group (Fig. 4a), indicating that after ischemia/reperfusion occurred, more GAP43 proteins accumulated in the ischemic penumbra, which was consistent with the high expression of GAP43 in OGD-treated cells.