Figure 4
Release of ROS, IL-1β and TNFα by quartz-treated NR8383 macrophages. A. Reactive oxygen species (ROS) formation by NR8383 macrophages in response to quartz treatment for 1 and 3 h at concentrations of 10 and 40 μg/cm2, measured by EPR spectroscopy in combination with the spin trap DMPO. The mean amplitude of the four peaks representing DMPO-OH adducts is expressed in arbitrary units. B. IL-1β and TNFα concentrations (pg/ml) measured by ELISA in non-diluted supernatants of NR8383 macrophages which were treated with 40 μg/cm2 quartz for 0.5 to 24 hours. *P < 0.05 and **P < 0.01 vs. control.