The M1 microglia-related protein CD11b began to be expressed 2 h after cerebral ischemia, and the activation and proliferation of CD11b-positive cells gradually peaked within 1 to 3 d after cerebral ischemia (∗P < 0.05versus the 3 d model group and ∗∗P < 0.01 versus the 3 d model group). This evidence concerns the gene ITGAM and Cerebral ischemia.