title: VR1-immunoreactive primary sensory neurons in the rat trigeminal ganglion.
abstract: Immunohistochemistry for VR1, a nociceptive transducer for vanilloid compounds, protons and heat (>43 degrees C), was performed on the rat trigeminal ganglion (TG). The immunoreactivity (IR) was detected in 20% of TG cells and these neurons were mostly small- to medium-sized (mean+/-S.D. 427+/-189 microm(2)). Twenty-six percent of the TG neurons retrogradely labeled from the facial skin exhibited VR1-IR, while the IR was detected in only 8% of those labeled from the tooth pulp. Co-expression of VR1 was common among the calcitonin gene-related peptide-immunoreactive cutaneous neurons (63%) but not among the similar tooth pulp neurons (20%). The present study indicates that primary nociceptive neurons which respond to vanilloid compounds, protons and heat are abundant in the facial skin but not in the tooth pulp.
authors.affiliation: Second Department of Oral Anatomy and Biodental Research Center, Okayama University Dental School, 2-5-1 Shikata-cho, Okayama 700-8525, Japan. hiroichi@dent.okayama-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Ichikawa
authors.forename: T
authors.initials: T
authors.lastname: Sugimoto
mesh_terms: D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis; D048429:Cell Size; D003782:Dental Pulp / Q000294:innervation; D007150:Immunohistochemistry; D008297:Male; D009475:Neurons, Afferent / Q000737:chemistry* / Q000166:cytology; D051381:Rats; D011955:Receptors, Drug / Q000032:analysis* / Q000276:immunology; D012867:Skin / Q000294:innervation; D050916:TRPV Cation Channels; D012668:Trigeminal Ganglion / Q000737:chemistry* / Q000166:cytology
chemical_list: D011955:Receptors, Drug; D050916:TRPV Cation Channels; C494484:TRPV1 receptor; D015740:Calcitonin Gene-Related Peptide