Identifying new nociceptor in skeletal muscle and its involvement in hyperalgesia

2016 Fiscal Year Final Research Report

• Project/Area Number: 26860161
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Environmental physiology(including physical medicine and nutritional physiology)
• Research Institution: Teikyo University
• Principal Investigator: OTA Hiroki 帝京大学, 医療技術学部, 助教 (10712432)
• Research Collaborator: TAGUCHI Toru 富山大学, 大学院医学薬学研究部, 客員准教授 ; MIZUMURA Kazue 中部大学, 生命健康科学部, 教授
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 痛み / 骨格筋 / 遅発性筋痛 / 末梢神経系 / 機械痛覚過敏

Outline of Final Research Achievements

The“silent nociceptor” is defined as a receptor that does not respond to mechanical stimulation in normal condition but responds to it in pathological condition. However, its existence has not been demonstrated in fibers innervating skeletal muscle. Here in this study we recorded C-fiber activities by in vivo single fiber recording technique, and investigated their axonal properties, their responses to noxious stimulation, and acquisition of the responsibility after injection of sensitizing substances. As a result, 7 of 58 mechanically insensitive C-fibers were presumed to be “silent nociceptors”, the proportion of which was different from other tissues. Among mechanically insensitive C-fibers, one of them got mechanical sensitivity after injecting a mixture of sensitizing substances (bradykinin, serotonin, prostaglandin E2, and histamine).

Free Research Field

環境生理学（含体力医学・栄養生理学）