title: Oxygen consumption by stimulated human neutrophils.
abstract: Oxygen consumption by stimulated human neutrophils has been studied. An initial lag after stimulation of about 20 s is followed by a linear phase of oxygen consumption which lasts about 60 s and then declines exponentially. The duration of the respiratory  burst is thus much shorter than has been generally recognized. The cessation of the linear phase of oxygen consumption occurs at a constant time after stimulation, is not due to depletion of the substrate of the oxidase enzyme (since linear oxygen consumption can be re-initiated), and is due to termination or saturation of particle uptake. The curtailment of oxygen consumption probably marks the end of the oxygen-dependent microbial role of the phagocytic vacuole, preparing it for the secondary and independent function of digestion. A novel cytochrome b becomes associated with the phagosomes and probably forms a component of a complex electron-transport chain. Superoxide may be an intermediate in this system, but it is unlikely to be released free from the cell or to form the final product of the system.
mesh_terms: D006105:Granulomatous Disease, Chronic / Q000503:physiopathology; D006801:Humans; D006861:Hydrogen Peroxide; D007074:Immunoglobulin G; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D009504:Neutrophils / Q000378:metabolism*; D010101:Oxygen Consumption; D010587:Phagocytosis; D012408:Rubber; D013481:Superoxides; D013696:Temperature; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D007074:Immunoglobulin G; D013481:Superoxides; D012408:Rubber; D006861:Hydrogen Peroxide; D009247:NADH, NADPH Oxidoreductases; D013755:Tetradecanoylphorbol Acetate