Fig. 6.

Effects of signal transduction inhibitors on mechanical stress (MS)-induced immune gene expression in periodontal ligament (PDL) cells. Cells were pretreated with the extracellular-regulated kinase (ERK) inhibitor SB203580 (20 µM), the p38 mitogen-activated protein kinase (MAPK) inhibitor PD98059 (20 µM), the c-Jun N-terminal kinase (JNK) inhibitor SP600125 (20 µM), the phosphoinositide 3 kinase (PI3K) inhibitor LY694002 (10 µM), the protein kinase C (PKC) inhibitor Ro-318220 (10 µM) or the nuclear factor (NF)-κB inhibitor pyrrolidine dithiocarbonate (PDTC) (10 µM) for 1 h, and then exposed to MS (12%) for 24 h. mRNA expression was examined by reverse transcription–polymerase chain reaction (RT–PCR). The data are representative of three independent experiments. The bar graph shows the fold increase in mRNA expression compared to control cells. *Statistically significant differences compared with the control, P < 0·05.