Effects of chemical kinase inhibitors on (A) AAH, (B) Humbug, and (C) Junctin mRNA levels in IGF-I stimulated SH-Sy5y cells. Subconfluent cultures were serum starved over night, then stimulated with IGF-1 and treated with vehicle (Con), or a chemical inhibitor of Akt, PKA (H-89), GSK-3β (LiCl), Erk MAPK (PD98059-PD9), Cdk-5 (Roscovitine-Rosc), or p38 MAPK (SB202190-SB2). Inhibitor concentrations are listed in Table 1. After 24 hours of growth factor stimulation, cells were harvested to measure (A) AAH, (B) Humbug, and (C) Junctin expression by real time quantitative RT-PCR as described in the legend for Figure 1. The mRNA levels were normalized to 18S rRNA levels measured in the same samples, and the graphs depict the mean ± S.D. of results. Statistical comparisons were made using ANOVA and post hoc Fisher LSD tests (**P < 0.001; *P < 0.01 relative to control).