Abstract: Objective To observe the Effects of PKC/NADPH oxidase on AGEs-induced eNOS uncoupling in rat cardiac microvascular endothelial cells Methods Cultured the cardiac microvascular endothelial cells in vitro. AGEs (100mg/l) 、 DPI and LY33531 （2.5μmol/L,5μmol/L and 10μmol/L ）respectively, was added and resumed incubation for 24 hrs. Meanwhile, a group managed with serum-free culture solution was assumed as blank control, we determined the BH4 、NO、O2-generation、 eNOS 、 ROS and p47phox protein expression of all groups. Results As LY33531 and DPI concentration was increased, production of NO was noted increased gradually(（90.67±0.33～122.58±0.26、160.58±0.58， P＜0.05) ,while production of O2- was decreased gradually(179.59±0.37～125.59±0.57、125.51±0.65，P＜0.05)，BH4 expression was seen increased (213.73±0.01～434.55±0.01、480.89±0.01，P＜0.05)， eNOS expression was seen gradually decreased (126.10±3.49～112.61±1.76、114.43±1.75，P＜0.05) .Meanwhile, p47phox protein expression and ROS was seen decreased gradually (P＜0.05). Conclusion AGEs may trigger the activation of PKC/NADPH oxidative stress pathway inducing intracellular eNOS uncoupling in cardiac microvascular endothelial cells.

Key words: BSA-AGEs, cardiac microvascular endothelial cells, NO, eNOS, PKC/NADPH, LY33531, DPI