Superoxide dismutase, catalase, glutathione peroxidase and NAD(P)H cytochrome c reductase were quantitated in polymorphonuclear leukocytes (PMN) and alveolar macrophages (AM) obtained from guinea pigs exposed up to 90 h to 85% oxygen. PMN and AM were sonicated and separated into a 16,000-g pellet, a 100,000-g pellet, and a 100,00-g supernate. Superoxide dismutase activity increased in both cell...