1,25-D3 reduced cerebral infarction volume, increased the recovery of CBF and expressions of VDR, TGF-β, p-Smad2, p-Smad3, and VEGF, significantly increased IB4+ tip cells and CD31+ vascular length in the peri-infarct area compared with the DMSO group. The gene discussed is SMAD2; the disease is brain infarction.