| Autor: |
Engels, Ferdi, Henricks, Paul A. J., van der Vliet, Helen, Nijkamp, Frans P. |
| Předmět: |
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| Zdroj: |
European Journal of Biochemistry; 9/1/89, Vol. 184 Issue 1, p197-203, 7p |
| Abstrakt: |
As guinea-pig pulmonary macrophages (PM) synthesize the linoleic acid metabolite 9-hydroxy-octadecadienoic acid (9-OH-Lin) under non- stimulated conditions in relatively large quantities, we investigated whether this product has an effect on the macrophage's own phagocytic cell function. 9-OH-Lin, and also its hydroperoxy precursor 9- hydroperoxy-octadecadienoic acid (9-OOH-Lin), influenced the generation of PM chemiluminescence, a measure of the production of reactive oxygen species. The generation of lucigenin-enhanced chemiluminescence by stimulated and non-stimulated PM was inhibited concentration-dependently. Inhibition was observed at concentrations as low as 10 nM. Since 9-OH-Lin and 9-OOH-Lin also inhibited the generation of chemiluminescence by a cell-free enzyme system, i.e. xanthine/xanthine oxidase, the inhibitory effects might represent a scavenging activity towards reactive oxygen species. 9-OH-Lin and 9-OOH-Lin did not influence other phagocytic cell functions, e.g. PM phagocytic capacity, the aggregatory response to the calcium ionophore A23187, or the release of lysosomal enzymes. The effects of 9-OH-Lin and 9-OOH-Lin could be ascribed to the hydroxy and hydroxyperoxy moiety, respectively, as evidenced by lack of effect of the native fatty acid linoleic acid. We conclude that the formation of 9-OH-Lin and 9-OOH-Lin by PM may represent a regulatory mechanism towards the cell's own activity by modulating reactive oxygen species. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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