Figure 10.

Akt is a critical mediator of BF neuron survival. A, BF neurons were grown in culture for 5 d and infected during the last 36 h with 50 MOI of adenovirus expressing either GFP or constitutively activated ras (ras V12) that was myc tagged. Neurons infected with control virus were identified by GFP labeling, and those infected with the rasV12 virus were identified by immunostaining for the myc tag. Uninfected and infected cultures were treated with pro-NGF for 5 h, fixed, and labeled with Hoechst to identify apoptotic nuclei. Data are expressed as percentage of apoptotic neurons. Triplicate cultures were analyzed in two independent experiments (n = 6). The asterisk indicates a value significantly different from all other groups at p < 0.05. Error bars indicate SEM. C, Control. B, BF neurons were grown for 5 d and treated overnight with the PI3K inhibitor LY294002 (LY) (50 μm) or the Mek1 inhibitor PD98059 (PD) (10 μm) alone or in combination with pro-NGF. Triplicate cultures were analyzed in three independent experiments (n = 9) and expressed as percentage of apoptotic neurons. The asterisk indicates a value significantly different from all other groups at p < 0.05. The double asterisk indicates a value significantly different from pro-NGF alone at p < 0.05. Error bars indicate SEM.