Decreased activity of NADPH oxidase in alveolar macrophages as a result of traumatic shock.

NADPH oxidase activity is significantly decreased in alveolar macrophages isolated from rabbits subjected to traumatic shock. In vitro studies indicate that activity of the enzyme is depressed in subcellular fractions of both resting and phagocytosing macrophages from shocked animals. Phagocytosis stimulates a twofold increase in NADPH oxidation in control alveolar macrophages, whereas NADPH oxidase activity is stimulated to a much lesser degree in macrophages from shocked animals. Results of this study suggest that the decreased activity of NADPH oxidase in alveolar macrophages from shocked animals may be associated with decreased bactericidal ability of the cells which was reported in a previous study (9).