Basophil releasability in young highly trained and older athletes

Purpose: Exercise-induced hypoxemia in highly trained athletes is associate d with an increase in histamine release during exercise. The cells most imp licated in blood histamine release are basophils. The aim of this study was to determine whether high-level endurance training induces modifications i n histamine releasability from human basophils. Methods: Seven young highly trained athletes (YA) [aged 26.1 +/- 1.3 yr (mean +/- SEM)] and seven mast er athletes (MA) (64.4 +/- 4.1 yr), all known to develop exercise-induced h ypoxemia, were respectively compared with seven young untrained men (YC) (2 3.0 +/- 1.5 yr) and seven older untrained men (OC) (61.6 +/- 1.3 yr). Durin g an incremental exhaustive exercise, blood samples for measurement of anti -IgE-induced histamine release from leukocytes were drawn at real, (V)over dot O-2max, and recovery. Results: Basophils from "leukocyte-rich" supernat ant in YA and MA showed significantly higher histamine release induced by a nti-IgE (1 mu g.mL(-1)) than, respectively, YC (P < 0.01) and OC (P < 0.05) at rest, (V)over dot O-2max (P < 0.01), and recovery (P < 0.01). Basophils in YA and MA also showed a histamine release induced by anti-IgE that was higher at (V)over dot O-2max than at rest (respectively, P < 0.01 and P < 0 .05), but this change was not found in the control groups. Conclusion: In c onclusion, the basophils in highly trained endurance athletes, both young a nd older, showed higher anti-IgE-induced histamine release than those of un trained men. This effect of high-level training seemed to be potentiated by exercise.