Interactions between sensory and emotions for chronic pain

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H05074
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Pain science
• Research Institution: Hyogo Medical University
• Principal Investigator: KOGA KOHEI 兵庫医科大学, 医学部, 講師 (50768455)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 前帯状回

Outline of Final Research Achievements

Chronic pain consists of sensory and emotional aspects, and both two aspects interact each other. However, the neural mechanisms and circuits on sensory-emotional interactions are still unknown. We focused on the anterior cingulate cortex (ACC), which is involved in chronic pain and anxiety, and studied the selective projections to form presynaptic long-term potentiation in the ACC. We found that the ACC receives inputs from thalamus mono-synaptically as well as poly-synaptically. Furthermore, an animal model of chronic pain attenuated GABAergic inhibitory synaptic transmission in the ACC. An electrophysilogical study showed that a chronic pain model reduced the release of GABA. When we activate muscarinic M1 receptors within the ACC, mechanical hypersensitivity was alleviated through facilitating muscarinic M1 receptors on GABAergic transmissions in the ACC.

Free Research Field

疼痛学

Academic Significance and Societal Importance of the Research Achievements

前帯状回皮質は、慢性疼痛と不安の形成に関わる大脳皮質の一つである。前帯状回における興奮性シナプスおよび抑制性シナプスが慢性疼痛によっていかに可塑的変化を形成するかや皮質内の局所神経回路が明らかになると、前帯状回における慢性疼痛や不安の仕組みが解明される。本研究結果は、上位中枢に作用する慢性疼痛に対する創薬開発に役立つ可能性がある。さらに、このような感覚がいかに情動や感情を形成し、相互に作用し合うかの神経分子機構が明らかとなると、様々な感覚ー情動系の解明に発展する広範囲な神経科学分野に貢献できる。