Fig. 4. The effect of succinyl acetone on TrkA, Raf, and MEK1/2 activation. PC12 cells were treated exactly as described in Fig. 3AD . Protein extracts were subjected to Western blotting analysis with antibodies against phospho(Tyr-490)-TrkA (A), phospho(Ser-259)-Raf (B), phospho(Ser-217/221)-MEK1/2 (C), total TrkA (D), total MEK1/2 (E), and total ERK1/2 (F), respectively.