NEUTROPHIL CHEMOTACTIC ACTIVITY IS INCREASED IN NASAL SECRETIONS OF LONG-DISTANCE RUNNERS

For years physicians have observed a high incidence of infections afte r strenuous exercise. Recent observations suggest an increase of neutr ophils in the upper airways following a long-distance race. In order t o elucidate mechanisms responsible for the influx of neutrophils in ai rway mucosa, we tested neutrophil chemotactic activity (NCA) in nasal lavages of amateur runners. Thirty-six amateur runners entered in a ma rathon race (42.2 km) and 24 healthy sedentary subjects participated i n the study. Nasal lavages (NAL) were performed several times before a nd after the race. The total number of recovered neutrophils was measu red and the NCA was determined using a modified Boyden chamber. The nu mber of PMNs in NAL of the runners immediately after the race was incr eased 2.7-fold (p < 0.01) compared to the values obtained on the same day prior to the race (128 +/- 19 vs. 48 +/- 16, x 10(3)), remained el evated several days after the race and returned to baseline after 1 we ek. The race resulted also in a 2.5-fold (p < 0.01) increase of NCA im mediately after the competition compared to the pre-race values of the same day (78 +/- 5.2 cells/8 High Power Fields, HPF vs. 31 +/- 3.4 ce lls/8 HPF). The findings suggest that NCA might play an important role in attracting neutrophils to the airways. The nature and origin of NC A in airway secretions is presently not known.