Figure 9. Effects of progesterone on IL-1β–induced MAPK and IκB-α phosphorylation in corneal fibroblasts. Cells were incubated in the absence or presence of progesterone (10 μM) for 12 h and then in the additional absence or presence of IL-1β (0.1 ng/ml) for 30 min. Cell lysates were then prepared and subjected to immunoblot analysis with antibodies to total or phosphorylated (P-) forms of ERK, JNK, p38 MAPK, or IκB-α. Data are representative of three independent experiments.