Figure 3. Horseradish peroxidase (HRP) permeability assay of bovine retinal capillary endothelial cells (BRCECs). Asymmetric dimethylarginine (ADMA) significantly increased HRP permeability in BRCECs. Treatment with benazepril and NAC for 15 min decreased HRP permeability in BRCECs. The permeability increase by ADMA was significantly downregulated by benazepril, telmisartan, diphenyliodonium (DPI), or N-acetyl-l-cysteine (NAC) for 30 min, 45 min, and 1 h. The group C bars are that BRCECs were cultured in endothelial cell medium (ECM) with 0.4% FBS. In group A, BRCECs were cultured in ECM with 0.4% FBS plus ADMA (100 μM). In group “A+B,” BRCECs were cultured in the same media as A and 10 μM benazepril. Group “A+T” was the same as for group A and 10 μM telmisartan. In group “A+D,” BRCECs were cultured in the same media as group A and 10 μM DPI. In group “A+N,” BRCECs were cultured in the same media as group A and 10 mM NAC (mean±SD, n=3). *p<0.05 versus group C, **p<0.01 versus group C, #p<0.05 versus group A, ##p<0.01 versus group A.