FIGURE 2.

SMP_LPS or SMP_PMA/I promote early oxidative stress and the up‐regulation of pro‐oxidant enzymes in P1ECs. P1ECs were incubated for 6 h either with 100 μmol/L H₂O₂, 10 nmol/L SMP_LPS or SMP_PMA/I before the determination of oxidative stress using the redox‐sensitive probe DHE (A), of mitochondrial ROS using MitoSOX Red (B). C, P1ECs were incubated for 30 min with inhibitors of either NADPH oxidase (VAS), cyclooxygenase (Indo) or of the mitochondrial respiratory chain complex (MKR) before the addition of 10 nmol/L SMP_LPS or SMP_PMA/I for 6 h, and the subsequent measurement of oxidative stress. D‐H, P1ECs were incubated for 24 h with 30 nmol/L SMP_LPS or SMP_PMA/I before determination of the expression of eNOS (D), iNOS (E) and NADPH oxidase subunits p22phox (F), p47phox (G) and p91phox (H) by Western blot. Immunoblots (upper panel) and densitometry analysis of cumulative data (lower panel). I, P1ECs were incubated for 30 min with inhibitors of either NADPH oxidase (VAS, VAS‐2870, 5 μmol/L) or cyclooxygenase (Indo, indomethacin, 30 μmol/L) before the addition of 10 nmol/L SMP_LPS or SMP_PMA/I for 48 h, and the assessment of SA‐β‐gal activity by flow cytometry. Data are expressed as mean ± SEM of experiments performed at least on three different cell cultures. **P < .01