Fig. (5) Effect of different inhibitors of ROS-generating enzymes on coumaric acid-induced modification of the intracellular ROS levels. Measurement of intracellular ROS generation in cultured human ECs in the absence (CTRL all panels) or presence of (A-D) 25 µM coumaric acid; (A) 10 µM rotenone, or 25 µM coumaric acid + 10 µM rotenone; (B) 1 mM L-NAME, or 25 µM coumaric + 1 mM L-NAME; (C) 10 µM AEBSF, or 25 µM coumaric acid + 10 μM AEBSF; (D) 20 μM DPI, or 25 µM coumaric acid + 20 µM DPI. Treatment-induced variation of fluorescence was kinetically measured every minute for 120 consecutive minutes as described in materials and methods. (Figure insets): Using as reference untreated cells, the overall anti- and pro-oxidant effect was extrapolate by comparison of the slope obtained from at least five kinetic measurements for each experimental condition. Data are expressed as percentage of control and represent the means ± SE of five different experiments. * Significantly different from CTRL at P<0.05. §, significantly different from 25 µM coumaric acid at at P<0.05