Fig. 2.

TH induction by electrical stimulation requires mRNA synthesis (A) and functional voltage-activated sodium channels (B). E16.5 PG neurons were stimulated at 5 Hz or with 40 mm KCl for 6 hr in the presence or absence of 0.5 μg/ml actinomycin D (A) or 1.5 μm tetrodotoxin (B). Each bar represents the percentage of total neurons exhibiting TH immunoreactivity. Data are presented as the mean ± SEM. Comparisons among groups were made using ANOVA followed by Duncan's multiple range test; ***p ≤ 0.001. Ctrl, Control.