[The toxic effect of oxygen on alveolar macrophages and granulocytes]

The exposure of guinea pigs to 85% oxygen increased in alveolar macrophages and granulocytes the Superoxid Dismutase activity. This enzyme protects aerobic organisms against the toxic superoxide anion. In contrast both cell types exhibited a decrease in hydrogen peroxide metabolizing enzymes Catalase and Glutathione perioxidase. In addition, the animal exposure to FiO2 of 85% impaired various phagocytic functions. A decrease of adherence, chemotaxis, ingestion rates as well as the bacterialcidal activity was observed in alveolar macrophages and granulocytes. In alveolar macrophages the degranulation was also diminished. These phagocytic function defects are caused by a cytoskeleton alteration, consistent of the microtubulus and microfilaments. The guinea pig exposure to a FiO2 of 85% did enhance the number of alveolar macrophages and granulocytes demonstrating a patchy FITC-Concannavalin A fluorescence, which is associated with a disruption of the microtubulus and the microfilaments. The phagocytic defects described in alveolar macrophages and granulocytes obtained from guinea pigs exposed to a FiO2 of 85% are based upon a microtubulus and microfilament disturbance in both cell types.