Impaired reannealing of the endothelial barrier after an increase in lung vascular permeability induced by PAR-1 activation in FoxM1 CKO mice. FoxM1 CKO mice or WT littermates were treated with either saline or a PAR-1 agonist peptide (i.v., 5 mg/kg BW). Lungs were isolated at the indicated times and perfused for K_f,c measurements. K_f,c was also measured at baseline (time 0). Data are expressed as mean ± SD (error bars; n = 3). *, P < 0.05 versus WT/agonist. Agonist, PAR-1 agonist peptide. Three independent experiments were performed with 20 WT and 21 FoxM1 CKO mice at the age of 3.5–4 mo old. FoxM1 CKO lungs exhibited persistent microvessel leakage after PAR-1 activation.