THE INFLUENCE OF VARIATION OF OXYGEN-TENSION ON THE PRODUCTION OF REACTIVE OXYGEN SPECIES BY HUMAN PHAGOCYTES

Reactive oxygen species (ROS) are frequently discussed in connection w ith the development of ischemia/reperfusion-induced damage to tissues. In our experiments the effect of variation of oxygen tension (5 to 70 kPa) on the production of ROS by human phagocytes was studied. Measur ements were performed in, vitro on the peripheral blood immediately af ter the respective oxygen tension was produced or following one-hour i ncubation at the respective tension. Further, the influence of one-hou r incubation of phagocytes in a hypoxic (P-O2, = 7 kPa) environment wi th reoxygenation to P-O2, = 70 kPa was tested. Spontaneous and starch grain- or opsonized zymosan-induced production of ROS was studied usin g the luminol-enhanced chemiluminescence method. Evidence was provided for a moderate increase in ROS production in dependence on the increa sing oxygen tension. There was no significant difference between the i ncubated and the non-incubated groups. Reoxygenation from P-O2, = 7 kP a to P-O2, = 70 kPa resulted in an increase by 15% of activated ROS pr oduction as compared with the group incubated for 1 hour in a hyperoxi c environment (P-O2 = 70 kPa) without previous hypoxia.