Fig. 4. MEK/ERK and PI3K/Akt, but not NF-B, are key components in the PMA-induced survival of SGNs. SGNs were treated for 24 hours with or without PMA at 100 nM and increasing concentrations of U0126 (U), LY294002 (LY) or 2 µM BAY 11-7082 (BAY) or 1 mM sulfasalazine (SZ) to reduce, respectively, the enzymatic activity of MEK, PI3K or NF-B complex. Neuronal survival was quantified, as determined in Fig. 2A (n=8; ^*P<0.05; ^**P<0.01).