Abstract: Endothelial dysfunction was closely related with AS, NO bioavailability (production and utilization of endothelial NO)was decreased by oxidative stress, lipid infiltration, inflammatory factor expression, vascular tone alteration and so on, which play an important role in endothelial dysfunction. Enhanced arginine, activityand asymmetric dimethylarginine together with increased hyperhomocysteinemia all promote AS by intervening NO bioavailability.Diabetes mellitus, obesity, chronic kidney disease, smoking and so on also involved in AS via influencing NO bioavailability and NO level.

Key words: atherosclerosis, endothelial dysfunction, nitric oxide, nitric oxide synthase, NO bioavailability