Effect of hyperoxia on reduced glutathione in alveolar macrophages and polymorphonuclear leukocytes

Reduced glutathione (GSH) protects alveolar macrophages (AMs) and polymorphonuclear leukocytes (PMNs) against oxidative damage. To obtain further knowledge of the oxygen toxicity we determined GSH in AMs and PMNs of guinea pigs exposed to an oxygen concentration of 85% for up to 90 h. AMs and PMNs from control animals contained 17.93 and 11.67 nmol GSH/mg protein, respectively. During the exposure to a FIO2 of 85% we observed a significant continuous increase of GSH in AMs. By 90 h of oxygen exposure, AMs contained 51.22 nmol GSH/mg protein. In addition, the protein content of AMs decreased during hyperoxia. In contrast, no change of the GSH amount and protein content was detectable in PMNs. The increase of GSH in AMs could serve as an adaptation of the cells to hyperoxia. The lack of the GSH increase in PMNs could be due to the different oxygen concentrations between the lung and the peritoneal cavity. The greater GSH content in AMs may account for the difference between these cells in their susceptibility to oxidant injury.