Superoxide production by phagocytes. Another look at the effect of cytochrome c on oxygen uptake by stimulated neutrophils.

The widely held view that stimulated phagocytes liberate $\text{O}{}_2{}^{\mathrm{?}}$ into the extracellular medium is supported by the alterations in oxygen uptake which occur when ferricytochrome $\text{c}$ is added to a suspension of zymosan-treated neutrophils. An explanation consistent with this view is provided for some previously reported results $\text{(}\text{FEBS Lett}\text{. 100}$, 27) which initially appeared to conflict with the notion that $\text{O}{}_2{}^{\mathrm{?}}$ is released by phagocytes.