In A, BAEC were transduced with control or Nox5 adenovirus at different MOIs (4 to 200). 36hrs post transduction, ROS production was monitored by chemiluminescence in the presence and absence of DPI (10μM). In B, NO release was measured from BAECs as described. The relative expression of eNOS and Nox5 (HA) was determined via Western blotting (lower panels). GAPDH was used as a loading control. The data are presented as mean±SE (n=5-6). *P<0.05 vs control or DPI. In C, HAECs were transduced with control or Nox5 adenovirus and 36hrs post-transduction, NO release was determined via cGMP accumulation in HASMC reporter cells. Cells were stimulated with ionomycin (1μM) and cGMP accumulation in SMC reporter cells was measured in the presence of SOD (100U/ml). The data are presented as mean±SE (n=4-6). *P<0.05 vs the untreated control, # in the presence of L-NAME and + P<0.05 vs β-gal.