Effect of sulphite on the oxidative metabolism of human neutrophils: Studies with lucigenin- and luminol-dependent chemiluminescence
✍ Scribed by Mishra, Anil ;Dayal, Niru ;Beck-Speier, Ingrid
- Publisher
- John Wiley and Sons
- Year
- 1995
- Weight
- 894 KB
- Volume
- 10
- Category
- Article
- ISSN
- 0884-3996
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✦ Synopsis
To assess the effect of sulphite on the oxidative metabolism of human neutrophils, chemiluminescence (CL) measurements were performed using lucigenin and luminol as chemiluminigenic probes. Lucigenin-dependent CL was used for measuring superoxide anion (0;) production, and luminol-dependent CL was used for determination of myeloperoxidase (MP0)-connected processes. With sulphite concentrations of 0.01 t o 1 mmol/L, resting neutrophils showed an up t o sixfold increase of lucigenin-dependent CL, but only a 1.9-fold increase of luminol-dependent CL. Subsequent stimulation of sulphite-treated neutrophils w i t h phorbol myristate acetate (PMA) (soluble stimulant) or zymosan (particulate stimulant) resulted in an additional significant increase of lucigenin-dependent CL compared t o stimulated control cells, whereas luminol-dependent CL increased slightly by 0.01 mmol/L sulphite and decreased then continuously. Sulphite concentrations above 1 mmol/L decreased both lucigenin-and luminol-dependent CL of resting and PMA-or zymosanstimulated neutrophils. Lucigenin-dependent CL of sulphite-treated and subsequently stimulated neutrophils was strongly inhibited by extracellularly added superoxide dismutase, whereas luminol-dependent CL was markedly reduced by the M PO inhibitor azide. The intracellular activity of MPO in neutrophils stimulated with PMA in the presence of sulphite (Smmol/L) was reduced by 55%. Sulphite (0.1 mmol/L) also inhibited strongly the activity of MPO in a cell-free system. These results indicate that micromolar concentrations of sulphite exert a stimulating effect on the 0; production of neutrophils extracellularly, but have an inhibitory effect on MPO-catalysed reactions intracellularly.