Expression of Shh, Ptc1, Ptc2 mRNA in the cap stage of mouse molar / 中华口腔医学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the expression of Shh and its receptors Ptc1 and Ptc2 mRNA in the cap stage of mouse molar and discuss its role in early tooth morphogenesis.</p><p><b>METHODS</b>The embryonic mouse heads of early tooth development (E10.5 - E15.5) were obtained and 5 micro m serial sections were made. Immunohistochemical staining of PCNA was carried out by SP method. The expression pattern of Shh, Ptc1, and Ptc2 mRNA was analysed by in situ hybridization.</p><p><b>RESULTS</b>E14.5, outer dental epithelium, inner dental epithelium, stellate reticulum and underlying dental mesenchyme were PCNA positive. Most of the enamel knot cells were PCNA negative. A few of the enamel knot cells were PCNA positive. Shh, Ptc1, and Ptc2 mRNA were strongly expressed in outer dental epithelium, inner dental epithelium, stellate reticulum and the enamel knot.</p><p><b>CONCLUSION</b>In the cap stage, Shh as a paracrine and autocrine signaling molecule might stimulate epithelium and mesenchyme proliferation.</p>