Publication details
Morphogenesis of Palatal Ridges in the Golden Hamster (Mesocricetus auratus, Rodentia)
| Authors | |
|---|---|
| Year of publication | 2005 |
| Type | Article in Periodical |
| Magazine / Source | Acta Veterinaria Brno |
| MU Faculty or unit | |
| Citation | |
| Field | Morphological specializations and cytology |
| Keywords | Oral cavity; proliferation; embryo; foetus; development |
| Description | Rugae palatinae (RP), transversal mucosal ridges of the mammalian palate, are assumed to play a role during closure of the palate in embryos. The aim of this study was to assess the morphogenesis of palatal ridges in the golden hamster (Mesocricetus auratus, Rodentia) by light and scanning electron microscopy. Cell proliferation was detected by immunohistochemical staining of proliferating cell nuclear antigen (PCNA). In the hamster, three to four antemolar and three intermolar ridges were formed. In ED 11.0 (ED = embryonic day) embryos, RP1 and RP3 were at the epithelial thickening stage, RP2 was a primitive ruga in the rostral part of the palatal processes. In the caudal part of the palate, an epithelial placode represented the prospective RP4-RP7. At ED 12.5, the closed secondary palate bore six ridge primordia. Only RP2 protruded distinctly into the oral cavity. At ED 13.0-14.5 and ED15.0-15.5, the mesenchymal core of the antemolar and intermolar ridge primordia, respectively, started to develop. Strikingly, a local increase of proliferation activity does not seem to be the main process involved in palatal ridge formation and elevation. Although the palatal ridge formation and elevation is based on tissue volume enlargement, strikingly, the proliferation activity was higher in the interrugal epithelium than in the ridge primordia. Rather than the epithelial proliferation activity increase, the change in orientation of mitotic spindles of dividing cells seems to be a reason of palatal ridge formation. |