Increase in blood bradykinin concentration after eccentric weight-trainingexercise in men

The purpose of this study was to verify the possible appearance in the bloo d of bradykinin (BK) and des-Arg(9)-bradykinin (des-Arg(9)-BK) after eccent ric exercise in 13 male subjects. Eccentric exercise (5 x 10 leg presses at 120% maximal voluntary concentric contraction) resulted in muscle damage a nd inflammation, as suggested by the significant increase in serum creatine kinase activity (from 204 +/- 41 to 322 +/- 63 U/l 12 h postexercise) and by severe lasting pain, which also peaked at 12 h postexercise. Blood BK an d des-Arg(9)-BK concentrations were measured by competitive enzyme immunoas says using highly specific polyclonal rabbit IgG. Des-Arg(9)-BK concentrati on was not modified (preexercise: 44 +/- 14 pmol/l; pooled postexercise: 47 +/- 4 pmol/l). In contrast, BK concentration significantly increased immed iately after the exercise session (68 +/- 9 vs. 42 +/- 3 pmol/l preexercise ) and returned to basal values at 12, 24, and 48 h (pooled value: 40 +/- 4 pmol/l). This observation suggests that the inflammatory process due to ecc entric exercise-induced muscle damage could be mediated in part by BK.