Acute psychological stress induces a prolonged suppression of the production of reactive oxygen species by phagocytes

Possible effects of psychological stress on the function of phagocytic cells have thus far hardly been investigated. In this study, we examined the phagocytic production of reactive oxygen species (ROS) in 10 healthy subjects undergoing a brief mental stressor. In a crossover design, the same subjects served as their own unstressed controls on a second experimental date. The acute laboratory stress resulted in a suppressed circadian rhythm of ROS production and in a decreased overall formation of ROS throughout the day. Especially under conditions of chronic stress, this finding may be of importance for the host's defense against infectious diseases. (C) 2003 Elsevier B.V. All rights reserved.