Nerves are less densely stained by an antibody to neurofilament in Nav2 homozygous mutant embryos at E11.5. The (A) mesencephalic tract (mes) nerve fibers, (C) cranial nerve XII, and (E) dorsal root ganglia (drg) nerves are shown in wild-type (WT) mice. (B, D, F) Nav2-/- littermates show decreased staining of nerve fibers in these same regions. The images shown here are representative of the majority of those scored in Table 1 as positive for a reduction of nerve fiber density. Scale bar: 100 μm.