FIGURE 5.

The NGF-induced MAPK pathway regulated TRPV4. A, NGF (100 ng/ml) increased the levels of PLA₂ and TRPV4 transcripts in PC12 cells, and these increases were inhibited by PD098059 (a MEK inhibitor). GAPDH mRNA was use to normalize PLA₂ and TRPV4 mRNA levels. B, NGF (100 ng/ml) increased the protein expression of PLA₂ and TRPV4 in PC12 cells probed by Western blot. α-Tubulin was blotted as a control. C, inhibitors of PLA₂ (AACOCF₃) and MEK (PD098059) suppressed NGF-induced neurite growth in PC12 cells, whereas an activator of PLA₂ (melittin) promoted NGF-induced neurite growth.