Regulation of the synergistic activity via the p38 MAP kinase pathway. Real time quantitative PCR shows that SB203580 (10 and 20 uM) blocks the synergistic effect of IL-1α and NTHi lysate, but PD98059 (10 and 20 uM) does not. Values are given as the mean ± standard deviation. N = 3. *: p < 0.05, **: p < 0.01. DMSO: dimethylsulfoxide.