Elucidation of chronic pain mechanism by approach from physiologically active substances, neural circuits and aging

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K18079
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 56020:Orthopedics-related
• Research Institution: University of Occupational and Environmental Health, Japan
• Principal Investigator: Matsuura Takanori 産業医科大学, 医学部, 非常勤医師 (90821679)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 慢性疼痛 / 神経可塑性 / 視床下部 / オキシトシン

Outline of Final Research Achievements

In chronic pain, changes in the central nervous system, including the limbic system, are considered to be an important area involved in emotions such as fear and anxiety. In this study, we investigated the mechanism of chronic pain, which increases with age, in relation to neuroplastic changes in the central nervous system (especially in areas involved in chronic pain) and descending pain inhibiting pathway (especially the hypothalamic oxytocin system) by means of bioactive substances such as inflammatory cytokines and matrix proteases (MMPs) released from the peripheral tissues. We investigated the relationship between the neuroplasticity in the central nervous system (especially in areas involved in chronic pain) and the decrease in the descending pain inhibiting pathway (with a particular focus on the hypothalamic oxytocin system) by using the Whole Cell Patch Clamp technique, and clarified part of the molecular system of this relationship.

Free Research Field

Chronic pain

Academic Significance and Societal Importance of the Research Achievements

超高齢化社会の日本において、運動器の慢性変性疾患を扱う整形外科医にとって、日常診療の中で骨粗鬆症ならびに変性疾患に伴う慢性疼痛患者といかに向き合うかというのは大きなテーマの一つである。近年、骨粗鬆症ならびに変性疾患の病態として持続性慢性炎症説があり、注目を集めているが、これらの慢性炎症性物質と慢性疼痛のメカニズムの関与については不明な点が多い。今研究では加齢に伴い増加する慢性疼痛の機序が、①大脳辺縁系領域での神経可塑性変化にて来たすこと、また②神経ペプチドを中心とする下行疼痛抑制系の低下にて来たす可能性があることを報告した。