Figure 4.

Immunohistochemical detection of nerve fibres in both functional teeth (full line) and replacement teeth (dashed line), on transverse paraffin sections of adult zebrafish stained with a primary antibody against acetylated tubulin (act). (A) Functional teeth clearly contain many small nerve fibres (arrowheads) in the dental pulp. (B) Replacement teeth (RT), however, are completely devoid of axons at all stages of differentiation. (C) Only at stages of very late cytodifferentiation, i.e. nearing attachment, could nerves (arrowheads) be seen entering the tooth at the base. Scale bars: 50 μm (A); 150 μm (B, C).