Anaphylatoxin C5a production during short-term submaximal dynamic exercise in man.
We studied the effects of short-term submaximal exercise on the plasma levels of myeloperoxidase ([MPO]) and C5a anaphylatoxin ([C5a]), taken as specific markers of polymorphonuclear neutrophil (PMN) and complement activation, respectively. Eleven young, healthy male volunteers were subjected to a constant-load concentric exercise on a cycle ergometer (20 min at 80% maximal oxygen uptake). Mean resting MPO and C5a concentrations were 437 +/- 113 and 0.47 +/- 0.21 ng/ml, respectively. During exercise, [MPO] and [C5a] increased significantly (p < 0.001) towards respective peak values of 649 +/- 131 and 1.3 +/- 0.6 ng/ml. A rapid decrease of both [MPO] and [C5a] was observed during recovery. The similar time course of [MPO] and [C5a] changes and the highly significant relationship between these two variables (r = 0.651; p < 0.001) argues for the possible involvement of the complement anaphylatoxin C5a in the process of PMN degranulation. During exercise, the number of circulating PMN increased (+80%; p < 0.001) and remained practically unchanged up to 20 minutes of recovery. As [MPO] and PMN count were not significantly related (r = 0.2; p < 0.1), we concluded that the activation of PMN was independent of their mobilization.
Camus
G
G
FNRS, Laboratory of Human Applied Physiology, ISEPK (B21), Sart Tilman, Liège, Belgium.
Duchateau
J
J
Deby-Dupont
G
G
Pincemail
J
J
Deby
C
C
Juchmès-Ferir
A
A
Feron
F
F
Lamy
M
M
D000328:Adult; D000704:Analysis of Variance; D015936:Complement C5a / Q000096:biosynthesis*; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D009504:Neutrophils / Q000201:enzymology* / Q000276:immunology*; D009195:Peroxidase / Q000097:blood*; D012016:Reference Values; D013997:Time Factors
D015936:Complement C5a; D009195:Peroxidase