Because endothelial activation, collagen synthesis within the vascular wall and atherosclerosis contribute to endothelial dysfunction and arterial stiffness, we measured blood pressure in Abcb8ECKO, Abcb8WT littermates and mutants carrying Abcb8 wild-type alleles and expressing tamoxifen-inducible endothelium-specific Cre (Cre) to address any Cre-mediated effect. The gene discussed is ABCB8; the disease is atherosclerosis.