Effects of pain on spinal motor control systems, and their influence on the process of functional recovery from central movement disorders.

Research Project

Project/Area Number	17K09796
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Neurology
Research Institution	Shinshu University
Principal Investigator	MORITA Hiroshi 信州大学, 学術研究院医学系, 教授 (10262718)
Project Period (FY)	2017-04-01 – 2023-03-31
Project Status	Completed (Fiscal Year 2022)
Budget Amount *help	¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000) Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000) Fiscal Year 2018: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000) Fiscal Year 2017: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Keywords	痛覚 / パーキンソン病 / H反射 / 運動調節 / 脊髄反射 / 小径繊維 / 無髄線維 / 小径線維 / Aδ線維 / C線維 / 痛覚刺激 / シナプス前抑制 / 相反性Ia抑制 / 無髄神経
Outline of Final Research Achievements	We studied the effects of pain on spinal monosynaptic reflex and spinal inhibitory pathways in normal and patients with Parkinson's disease.A-delta fiber stimulation on dorsal foot has facilitatory effects on the soleus H reflex with a latency around 200ms and a maximum around 250ms, and showed enhancing Ia inhibition, but did not affect D1 inhibition and inhibition induced with tendon tapping of biceps femoris. C-fiber stimulation also had facilitatory effect with a latency of 800-1000ms and a maximum between 1500 and 1800ms, but did not affect reciprocal inhibition and D1 inhibition, A-delta and C-fiber stimulation in the dorsal foot had a stimulatory effect on the soleus H reflex, and A-delta stimulation enhanced reciprocal Ia inhibition.
Academic Significance and Societal Importance of the Research Achievements	これまでの脊髄運動調節機構への末梢からの入力の影響は伝導速度の速い求心線維に由来する経路が研究されてきたが、痛覚のように伝導速度の遅い成分の効果は殆ど検討されていなかった。今回の研究では新たに開発された選択的に伝導速度の遅い痛みを感じる小径有髄神経と無髄線維を刺激し、その運動調節機構への影響を観察した。痛みは機能回復訓練における阻害因子となるだけでなく、随意運動の遂行にも影響を与えているが、その運動調節神経機構への影響を観察する試みは、類をみないアプローチである。