Immunofluorescent localization of myosin, alpha-actinin and tropomyosin in odontoblast microfilament bundles of the rat incisor

The localization of alpha-actinin, tropomyosin, myosin and actin in odontoblasts was examined by fluorescence microscopy using well characterized antibodies and rhodamine-phalloidin. All the reagents labeled the distal end of the cell body in the form of an oval ring with a preferential axis along the tooth axis. This ring was often interrupted. In conventional electron microscopy, microfilament bundles with periodical dense spots were running along the tooth axis at the level of the distal end of the cell body. The periodicity was about 0.6-1.0 microns. It may be possible that this dynamic structure functions to keep odontoblasts in a layer by contracting in an isometric form.