The rats in the SCI, SCI + BMSCs, SCI + BMSCs + SDF-1, SCI + BMSCs + AMD3100 and SCI + BMSCs + SDF-1 + AMD3100 groups had symptoms including edema of spinal cord, ischemia, paralysis of hind limb, involuntary spastic swing of small amplitude in rat tail; and spasm, curl, high tension and twitch were also found after rat tail was pressed by fingers. This evidence concerns the gene CXCL12 and ischemia.