Figure 1

Schematic diagram of experimental protocol. Mice were sensitized at day 1 and 14, and challenged at day 24, 25, 26 with OVA or saline. Dexamethasone or saline was administrated intraperitoneally 1 hr before each challenge. Equal number of mice were selected to expose to 1.0 ppm O₃ or filtered air for 3 consecutive hrs on day 23, 25 and 27. In p38 MAPK inhibition experiment, same amount of animals were injected through tail vein with SB239063 or DMSO. On day 28, measurements were performed including enhanced pause (P_enh), BAL cells and cytokines, lung tissues for pathological staining and biological testing.