The nerve mechanisms underlying tongue-referred pain associated with tooth pulp inflammation in trigeminal ganglion cells

• Project/Area Number: 26893288
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Conservative dentistry
• Research Institution: Nihon University
• Principal Investigator: OHARA Kinuyo 日本大学, 歯学部, 専修医 (10731606)
• Project Period (FY): 2014-08-29 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000); Fiscal Year 2015: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2014: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 歯髄炎 / 三叉神経節 / 異所性異常疼痛

Outline of Final Research Achievements

The purpose of the present study is to evaluate the mechanisms underlying tongue-referred pain associate-ed with tooth pulp inflammation through TLR4 signaling in trigeminal ganglion cells.
These results are the first documentation that TLR4 is involved in the ectopic tongue pain associated with M1TP inflammation. Following M1TP inflammation, Hsp70 is expressed in the pulpal tissues, transported to the cell bodies of the trigeminal ganglion neurons, or Hsp70 is expressed in TG cells, and then released from TG neurons innervating the inflamed M1TP. Hsp70 binds to TLR4 in TG neurons innervating the tongue, and the excitability of TG neurons innervating the tongue may be enhanced, resulting in ectopic tongue pain.

Research Products

• [Journal Article] 歯内療法における打診痛を考察する (2016)
  • Author(s): 清水康平，羽鳥啓介，大原絹代，篠田雅路，小木曾文内
  • Journal Title: 日本歯科評論 Volume: 76(3) Pages: 47-58
• [Journal Article] Involvement of trigeminal transition zone and laminated subnucleus caudalis in masseter muscle hypersensitivity associated with tooth inflammation. (2014)
  • Author(s): Shimizu K, Matsumoto K, Noma N, Matsuura S, Ohara K, Komiya H, Watase T, Ogiso B, Tsuboi Y, Shinoda M, Hatori K, Nakaya Y, Iwata K.
  • Journal Title: PLoS One Volume: 9 Pages: 1-11
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Presentation] Toll-like receptor 4 in the trigeminal sensory neurons is involved in tongue-referred pain following tooth pulp inflammation (2015)
  • Author(s): Kinuyo Ohara, Kohei Shimizu, Masamichi Shinoda, J Lee, Bunnai Ogiso and Koichi Iwata
  • Organizer: 9th Congress of the EUROPIAN PAIN FEDERATION EFIC
  • Place of Presentation: VIENNA, AUSTRIA
  • Year and Date: 2015-09-02 – 2015-09-05
• [Presentation] Toll-like receptor 4 in the trigeminal sensory neurons is involved in tongue-referred pain following tooth pulp inflammation (2015)
  • Author(s): Kinuyo Ohara, Kohei Shimizu, Masamichi Shinoda, Bunnai Ogiso and Koichi Iwata
  • Organizer: 9th Congress of the European Pain Federation EFIC
  • Place of Presentation: Vienna(AUSTRIA)
  • Year and Date: 2015-09-02
  • Int'l Joint Research
• [Presentation] 歯髄の炎症はToll-like Receptor４の働きを介して舌の異常疼痛を誘導する (2014)
  • Author(s): 大原 絹代, 清水 康平, 林 誠， 井比 陽菜， 小木曾 文内
  • Organizer: 日本歯科保存学会秋季学術大会(第141回)
  • Place of Presentation: 山形テルサ(山形県山形市)
  • Year and Date: 2014-10-30 – 2014-10-31