Compared with the MCAO group, the administration of exogenous tissue kallikrein starting at 8 h, 24 h, and 36 h after ischemic stroke can promote cell proliferation in the ipsilateral SVZ (Figures 2(a, C–E) and 2(b)) and in the peri-infarction area (Figures 3(a, C–E) and 3(b)). This evidence concerns the gene KLK4 and ischemic stroke.