Table 2. EC50 values for noradrenaline, in the absence or presence of indomethacin or L-NAME, obtained in two rings, one with and the other without endothelium, of the same thoracic aorta from sedentary and trained rats, submitted or not to stress.
| Inhibitor | Groups | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sedentary | Trained | Stressed | Trained/Stressed | |||||||||||||
| +E | N | –E | N | +E | N | –E | N | +E | N | –E | N | +E | N | –E | N | |
| Without | 2.41 (1.53-3.79) | 9 | 0.11† (0.09-0.16) | 9 | 2.67 (1.68-4.24) | 10 | 0.02† (0.01-0.10) | 10 | 1.44 (1.00-2.09) | 9 | 0.03† (0.01-0.18) | 8 | 5.34 (3.27-6.64) | 10 | 0.11† (0.01-0.21) | 8 |
| Indomethacin | 0.29* (0.13-0.61) | 8 | 0.06† (0.01-0.30) | 8 | 0.26* (0.07-0.97) | 7 | 0.05† (0.02-0.14) | 7 | 0.41* (0.10-1.66) | 8 | 0.07† (0.02-0.22) | 8 | 2.51 (1.17-5.38) | 8 | 0.08† (0.04-0.17) | 8 |
| L-NAME | 0.09* (0.01-0.12) | 7 | 0.10† (0.05-0.30) | 7 | 0.11* (0.04-0.31) | 8 | 0.08† (0.04-0.16) | 9 | 0.10* (0.03-0.43) | 7 | 0.04† (0.01-0.10) | 8 | 0.10* (0.01-1.11) | 8 | 0.12† (0.02-0.10) | 8 |
Values are EC50 (x10-7M): concentration of noradrenaline producing a response that was 50% of the maximum effect; (+E: with endothelium; (-E): without endothelium; stress: immobilization for 2 h; physical training: 60-min swimming session/5 days/week during 8 weeks, with 5% body weight load attached to the chest; values are means with 95% confidence interval. *P<0.05 presence of inhibitor vs absence of inhibitor, in rings with endothelium. †P<0.05 relate to rings with endothelium; (N) = number of animals; the data were compared by two-way ANOVA and complemented with the multiple comparisons Tukey's test.