Comparative studies on alveolar macrophages and polymorphonuclear leukocytes. I. H2O2 and O2- generation by rabbit alveolar macrophages.
The oxidative metabolism of rabbit alveolar macrophages (A-MO) was compared with that of rabbit polymorphonuclear leukocytes (PMN) with respect to H2O2 generation by intact cells or subcellular fractions. Rabbit PMN exhibited an increase in the oxygen uptake and a marked release of H2O2 upon addition of heat-killed E. coli in the presence and absence of opsonin. However, rabbit A-MO exhibited an increase in the oxygen uptake upon addition of E. coli only in the presence of anti-E. coli serum as an opsonin, whereas a very small amount of H2O2 release was observed during ingestion of the opsonized E. coli. The generation of O2- and H2O2 by a granule-rich fraction isolated from phagocytosing PMN was larger than that by a similar fraction isolated from resting PMN. However, there was no significant difference in O2- and H2O2 generation by the granule fractions between phagocytosing and resting A-MO in the presence of either NADH or NADPH. In contrast to the granule fraction of rabbit PMN, the O2- and H2O2 generating activities in the A-MO granule fraction were higher in the presence of NADH than in the presence of NADPH. The rates of NADH and NADPH oxidation by both A-MO and PMN granule fractions were measured with and without addition of Mn2+ to the assay medium. The effect of Mn2+ on the NAD(P)H oxidase was found to differ between rabbit A-MO and PMN.
D000818:Animals; D004926:Escherichia coli; D006861:Hydrogen Peroxide / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism*; D009504:Neutrophils / Q000378:metabolism*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D010587:Phagocytosis; D011817:Rabbits; D013347:Subcellular Fractions / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism*
D013481:Superoxides; D006861:Hydrogen Peroxide; D010100:Oxygen