Effect of stress on the production of O(2)(-) in alveolar macrophages.

Alveolar macrophages (AM) of male rats (200-250 g), stressed or not, were evaluated with relationship to superoxide production (SP). Plasma levels of corticosterone were measured. The control group showed larger SP than the stressed group in all intervals of time. Exposure in vitro of AM to a synthetic glucocorticoid for 40 min (the same time of restraint stress) inhibits SP. Therefore, it seems under stress situations there is an increase of plasma levels of corticosterone and a decrease of SP in AM after stimulation with PMA. O(2)(-) is a potent microbicide and its reduction could cause the loss of microbicidal activity of AM.