Purpose: Endurance exercise training can ameliorate many cardiovascular and metabolic disorders and attenuate responses to inflammatory stimuli. The purpose of this study was to determine whether the angiogenic and pro-inflammatory cytokine response to acute endurance exercise differs between endurance-trained and sedentary young men. Methods: Ten endurance-trained and ten sedentary healthy young men performed 30 min of treadmill running at 75 % VO with blood sampling before and after exercise. Plasma concentrations of tumor necrosis factor (TNF)-alpha, interleukin (IL)-8, IL-6, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), placental growth factor (PlGF), and soluble VEGF receptor-1 (sFlt-1) were measured by multiplex ELISA. Results: Acute exercise increased IL-6 by 165 % ( P < 0.05), IL-8 by 32 % ( P < 0.05), PlGF by ~16 % ( P < 0.05), sFlt-1 by 36 % ( P < 0.001), and tended to increase bFGF by ~25 % ( P = 0.06) in main effects analyses. TNF-α and VEGF did not change significantly with exercise in either group. Contrary to our hypothesis, there were no significant differences in TNF-α, IL-6, VEGF, bFGF, PlGF, or sFlt-1 between groups before or after acute exercise; however, there was a tendency for IL-8 concentrations to be higher in endurance-trained subjects compared to sedentary subjects ( P = 0.06). Conclusions: These results indicate that 30 min of treadmill running at 75 % VO produces a systemic angiogenic and inflammatory reaction, but endurance exercise training does not appear to significantly alter these responses in healthy young men. [ABSTRACT FROM AUTHOR]