Stobadine-modulated human neutrophil functional responsiveness: effect on particular and soluble stimulation.

The effect of stobadine on degranulation (myeloperoxidase release) and on oxidative burst, measured as superoxide anion production, was investigated in human neutrophils activated with receptor-specific (fMLP, opsonized zymosan) and nonreceptor stimuli (PMA, A 23187). Wortmannin, a specific inhibitor of 1-phosphatidylinositol 3-kinase, significantly inhibited fMLP-stimulated generation only. This effect was pronounced by stobadine. Stobadine dose-dependently decreased superoxide generation and myeloperoxidase release after receptor-specific stimuli, with the highest effect on fMLP stimulation of superoxide generation and on opsonized zymosan stimulation of myeloperoxidase release.