Figure 2.

Inhibition of 5-LOX product formation by RF-Id in intact cells. (A) Neutrophils were pre-incubated with RF-Id for 15 min at 37°C and stimulated with 2.5 μM A23187 plus AA as indicated for 10 min at 37°C. Data are means ± SEM; n = 3. (B) Intact neutrophils were pre-incubated with RF-Ic or RF-Id for 15 min, 37°C and stimulated with 2.5 μM A23187 plus 20 μM AA for 10 min at 37°C. Data are expressed as percentage of vehicle control (0.1% DMSO); means ± SEM; n = 3. (C) Neutrophils were primed for 15 min with 1 μg·mL⁻¹ LPS at 37°C, after 5 min 0.3 U·mL⁻¹ Ada was added for 10 min, and cells were then pre-incubated with the compounds (RF-Id, left panel; zileuton, right panel) for 15 min at 37°C before stimulation with 1 μM fMLP for 5 min at 37°C. Mononcytes were primed with 1 μg mL⁻¹ LPS at 37°C for 5 min, then compounds were added for 15 min, and cells were stimulated for 10 min at 37°C with 1 μM fMLP. Data are expressed as percentage of vehicle control (0.1% DMSO); means ± SEM; n = 3. (D) Effects of RF-Id on LTB₄ and cysLT formation in monocytes. Monocytes were primed with 1 μg mL⁻¹ LPS at 37°C for 5 min, then compounds (RF-Id, left panel; zileuton, right panel) were added for 15 min, and the cells stimulated for 10 min at 37°C with 1 μM fMLP. LTB₄ was quantified by HPLC and cysLT levels were analysed by elisa in supernatants respectively. Data are expressed as percentage of vehicle control (0.1% DMSO); means ± SEM; n = 3.