Mechanisms of referred pain; physiological interaction between oral & maxillofacial pain and visceral diseases

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K17209
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 57060:Surgical dentistry-related
• Research Institution: The Nippon Dental University
• Principal Investigator: Ide Ryoji 日本歯科大学, 生命歯学部, 講師 (10638084)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 関連通 / 篩状神経節 / ナトリウムチャネル / パッチクランプ法 / Dexmedetomidine

Outline of Final Research Achievements

Dexmedetomidine (DEX), an α2-adrenergic agonist, is a sedative and an analgesic, and on the analgesic effect the DEX-related inhibition of tetrodotoxin-resistant voltage-dependent sodium currents (Resurgent sodium currents, INaR) has been suggested to be involved. However, this mechanism has not been examined on visceral pain. Therefore, in this study, we dissociated neonatal rat nodose ganglion neurons, which convey visceral sensation, and measured the INaR by using the whole-cell patch-clamp technique. We found that DEX suppressed the INaR in a dose-dependent manner (IC50 = 128 μM). Therefore, present results suggest a possibility that the DEX has inhibitory effect on the visceral pain.

Free Research Field

生理学

Academic Significance and Societal Importance of the Research Achievements

心筋梗塞などの心疾患や肺癌、腹部内蔵疾患では三叉神経領域にしばしば関連痛が出現することが知られている。しかし、現在までその詳細な機序は未だ不明である。そこでα2アドレナリン作動薬で鎮静薬として知られているDexmedetomidine (DEX)を用いることにより内臓痛に抑制的な効果（鎮痛）をもつことが新たに示唆された。