Haploinsufficiency of endothelial Rac1 in mice leads to neuroprotection. EC-Rac1+/− and control mice underwent 2-hour MCAo followed by 22-hour reperfusion. (A) Representative brain sections stained with 2,3,5-triphenyltetrazolium chloride visualizing the infarct area. (B and C) Infarct (B) and edema (C) volumes of the ischemic hemisphere. (D) Neurological deficit score (n = 19 to 23 mice; *P < 0.05, Mann-Whitney test). (E) Change in CBF in the ischemic hemisphere at the end of 2-hour MCAo. (B, C, and E) Values are percent of the nonischemic hemisphere and shown as means ± SEM of 7 to 10 mice (*P < 0.05, ANOVA). NS, not significant.