Fig. 7.

Developmental changes of Nav1.2 distribution in mouse brain. Brain sections of wild-type mice at P0.5 (a, f, k, p), P2.5 (b, g, l, q), P7.5 (c, h, m, r), P15.5 (d, i, n, s), and 8-week-old (e, j, o, t) were stained with anti-Nav1.2 (G-20, red). Higher-magnified images outlined in a–e are shown in f–t. Nav1.2 immunoreactivities were observed at AISs of neocortical neurons (single black arrowheads), nodes of Ranvier within white matter (double black arrowheads), AISs of hippocampal pyramidal neurons (white arrowheads), mossy fibers of dentate granule cells (black arrows), etc. Note that, while Nav1.2 at AISs and nodes of Ranvier peaked at P15.5 and became less at 8-weeks, diffused Nav1.2 signals in neocortex continued to become dense until 8-weeks-old. The brain slices were processed in parallel. Representative images of four or more slices per stage are shown. MZ marginal zone, UCP upper cortical plate, LCP lower cortical plate, DG dentate gyrus, WM white matter, IZ intermediate zone, o stratum oriens, p stratum pyramidale, l stratum lucidum, r stratum radiatum. Scale bars: a–e 500 µm; f–o 50 µm; p–t 100 µm