Effect of PI3K- and MEK-inhibitors on STZ-induced eosinophil respiratory burst. Eosinophils (1.6 × 10⁶/mL) were preincubated with wortmannin (100 nm, 5 minutes, lanes 4 and 7) or PD098059 (50 μmol/L, 15 minutes, lanes 3 and 6). Cells were then primed with IL-5 (10⁻¹⁰ mol/L, 20 minutes, lanes 2 to 4) or PAF (10⁻⁶ mol/L, 2 minutes, lanes 5 to 7) before addition of STZ (1 mg/mL). Oxygen uptake was continually measured and results represent the maximal rate (nmolO₂/10⁶cells/min) of four experiments ± SE (P < .05, Student's t-test).