title: Neurocalcin-immunoreactive primary sensory neurons in the trigeminal ganglion provide myelinated innervation to the tooth pulp and periodontal ligament.
abstract: The distribution of neurocalcin-immunoreactive (NC-ir) primary sensory neurons was examined in the trigeminal ganglion (TG), mesencephalic trigeminal tract nucleus (Mes5) and intraoral structures. NC-ir primary sensory neurons were located in the TG but not the Mes5. The coexpression study demonstrated that virtually all NC-ir TG neurons exhibited S100-immunoreactivity (-ir). In the tooth pulp, NC-ir nerve fibers were observed in the subodontoblastic and odontoblastic layers. Immunoelectron microscopic and retrograde tracing methods revealed that myelinated pulpal axons derived from the TG mostly exhibited the ir. In the periodontal ligament, bush-like endings showed NC-ir. These endings were morphologically identical to Ruffini-like endings. The present study suggests that NC-ir trigeminal primary sensory neurons have their cell bodies in the TG. Their peripheral axons are probably myelinated. Such neurons include pulpal nociceptors and low-threshold mechanoreceptors.
authors.affiliation: Second Department of Oral Anatomy, Okayama University Dental School, 2-5-1 Shikata-cho, Okayama, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Ichikawa
authors.forename: H
authors.initials: H
authors.lastname: Hidaka
authors.forename: T
authors.initials: T
authors.lastname: Sugimoto
mesh_terms: D000818:Animals; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D003782:Dental Pulp / Q000294:innervation* / Q000378:metabolism* / Q000648:ultrastructure; D007150:Immunohistochemistry; D008297:Male; D008465:Mechanoreceptors / Q000378:metabolism* / Q000648:ultrastructure; D008854:Microscopy, Electron; D009413:Nerve Fibers, Myelinated / Q000378:metabolism* / Q000648:ultrastructure; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D051596:Neurocalcin; D009475:Neurons, Afferent / Q000166:cytology / Q000378:metabolism*; D010513:Periodontal Ligament / Q000294:innervation* / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D044169:Receptors, Calcium-Sensing; D012668:Trigeminal Ganglion / Q000166:cytology / Q000378:metabolism*; D014278:Trigeminal Nuclei / Q000166:cytology / Q000378:metabolism
chemical_list: D002135:Calcium-Binding Proteins; D009419:Nerve Tissue Proteins; D051596:Neurocalcin; D044169:Receptors, Calcium-Sensing; C496690:Vsnl1 protein, rat