Figure 3. Effects of LPA on MAPK phosphorylation in DPF. Serum-starved DPF were exposed to LPA at a concentration of 10 µM for 5, 15, 45, and 135 min. Cell lysates were separated on a 10% SDS-PAGE and blotted onto a nitrocellulose membrane. Phosphorylated (pERK, pp38 MAPK, and pJNK) and unphosphorylated MAPKs were detected by Western blot analysis.