Figure 3. Concentration-effect curves for noradrenaline, in the presence or absence of indomethacin (10-5 M) or L-NAME (3x10-4 M), obtained in two rings, with and without endothelium, of thoracic aortas from 16-week old rats. Groups: (S) sedentary; (T) trained (60-min swimming sessions, 5 days/week during 8 weeks, with a 5% body weight load attached to the chest); (St) submitted to acute stress (immobilization for 2 h); and (T/St) submitted to both procedures. *P<0.05 presence of indomethacin vs absence of inhibitor. †P<0.05 presence of L-NAME vs absence of inhibitor. Values are means ± SEM of 7-10 animals per group. The data were compared by two-way ANOVA and complemented with the multiple comparison Tukey's test.