Corticosterone, prolactin and thyroid hormones as hormonal mediators of the stimulated phagocytic capacity of peritoneal macrophages after high-intensity exercise.

The aim of this study was to evaluate the effect of high-intensity physical activity (swimming until exhaustion) with or without previous training on the phagocytosis and destruction of inert particle capacities of macrophages, and the role of corticosterone, prolactin and thyroid hormones as possible hormonal mediators. The results indicated that high-intensity exercise provokes a stimulation of both phagocytosis and destruction of inert particles when performed in absence of previous training. However, swimming until exhaustion after a one month training program (25 min/day) induced an increase in phagocytosis but not in the destruction of latex beads. Corticosterone, prolactin and thyroid hormones can be considered as hormonal mediators of the exercise-induced stimulation of phagocytosis, since these hormones increased plasma concentration, and the in vitro incubation of macrophages with the same higher physiological plasma concentrations of each hormone, as after exercise, also induced phagocytic stimulation of these cells.