Figure 9.

Neurotransmitter expansion in the VSC and spinal cord of activity-manipulated larvae. A, The number of TH neurons in the VSC core and annulus increases upon overexpression of rNa_v2a αβ. Expansion of the TH phenotype occurs within the Lim1,2 population in both core and annulus (**p < 0.01, ***p < 0.001, compared with control by the Mann–Whitney U test), and the expansion in the annulus is significantly greater than the expansion in the core (*p < 0.05, comparing normalized control with rNa_v2a αβ values for the core and annulus with the Kruskal–Wallis test followed by the Conover's post hoc analysis). Stage 42; values are mean ± SEM for n = 6 embryos. B, rNa_v2a αβ overexpression expands the TH phenotype within the ventral GABA⁺ population of the spinal cord (*p < 0.05, comparing control vs rNa_v2a αβ values by the Mann–Whitney U test), increasing the number of clusters of TH⁺/GABA⁺ cells (*p < 0.05, comparing control vs rNa_v2a αβ values by the Mann–Whitney U test). Stage 35; values are mean ± SEM for n ≥ 4 larvae.