Fig. 5.

ATX-induced neurite extension involves a Src family kinase. A, representative images (scale bar, 10 μm) and quantification of neurite extension at 24 h (B). Cerebrocortical neurons were treated with 30 nM ATX in the presence or absence of either 2 μM PP2 or PP3 beginning at 3 h after plating. The experiment was repeated four times, and 20 to 30 neurons were quantified for each exposure condition. ***, p < 0.001, *, p < 0.05, unpaired t test. C, tyrosine phosphorylation (Tyr416) of Src kinase determined by immunoblotting. Cerebrocortical neurons were treated with 30 nM ATX beginning at 3 h after plating, and P-Src (Tyr416) was assessed at the indicated times. A representative blot is shown. The experiment was performed twice with independent cultures. Also depicted is the quantitative analysis of the relative band densities of immunoblots. Each bar represents mean ± S.E.M. of two values.