RELEASE OF CYTOKINES BY BLOOD MONOCYTES DURING STRENUOUS EXERCISE

During strenuous exercise in endurance athletes, monocytes are activat ed and there is an acute inflammation and hypoxemia possibly due to le sional pulmonary edema. IL-6 and TNF-alpha released by monocytes may b e implicated in the acute phase of lesional pulmonary edema. A study w as carried out to determine whether TNF-alpha and IL-6 are released du ring strenuous exercise, and, if adrenalin released during exercise al ters their generation. Ten young and six master athletes underwent an incremental exercise test. Arterial blood was drawn at rest, at the en d of the exercise, and 20 minutes afterwards. Monocytes were isolated and incubated for 18 hours in the presence or absence of adrenalin. IL -6 and TNF-alpha were measured in monocyte supernatants. The spontaneo us release of IL-6 or TNF-alpha was increased in young athletes when c ompared to older subjects. The spontaneous release of TNF-alpha was in creased, but not significantly, by exercise and there was no correlati on between the release of IL-6 and TNF-alpha and lung function measure d during hypoxemia. Adrenalin inhibited the release of IL-6 or TNF-alp ha. Correlations were observed between the in vitro release of IL-6 or TNF-alpha and age, VO(2)max, maximal ventilation and maximal power ou tput of the subjects.