Fig. 9: Navβ4 mRNA and intrinsic excitable properties in RA of female zebra finches across ages.
From: Resurgent Na+ currents promote ultrafast spiking in projection neurons that drive fine motor control
a Representative in situ hybridization images for Navβ4 across ages (days post hatch, dph); black arrowheads indicate RA borders. b Views of adjacent sections to those in (a), stained for Nissl; black arrowheads indicate RA borders. c Comparison of Navβ4 expression levels (normalized optical density) across age groups within RA (one-way ANOVA with Tukey’s post hoc; P = 0.06, F (2, 10) = 3.290, N (birds/age) = 5/20 dph, 4/35 dph, and 4/50 dph females). Data are presented as individual data points with bars as mean values ± SEM. d Comparison of the proportions of Navβ4-expressing cells across age groups within RA (one-way ANOVA with Tukey’s post hoc; P = 0.0001, F (2, 10) = 24.95; N (birds/age) = 5/20 dph, 4/35 dph, and 4/50 dph females). Data are presented as individual data points with bars as mean values ± SEM. e Representative currents from RAPNs at each age group during the −30 mV test potential shown at the top. The large INaT peaks have been truncated. f Average I–V curves for the peak INaR in RA neurons at each age group; no significant groups differences seen (two-way ANOVA with Tukey’s post hoc; P = 0.83, F (12, 140) = 0.6103, N (cells/age) = 9/20 dph, 10/35 dph, and 4/50 dph females). Data are presented as mean values ± SEM. Gray dashed line shows I–V relationship for 50 dph male (same as in Fig. 4c). g I–V curves after normalization of the peak INaR to the peak INaT measured in a given sweep then averaged across cells (two-way ANOVA with Tukey’s post hoc; P = 0.48, F (12, 140) = 0.9678, N (cells/age) = 9/20 dph, 10/35 dph, and 4/50 dph females). Data are presented as mean values ± SEM. Gray dashed line shows I–V relationship for 50 dph male (same as in Fig. 4d).
