Physiological function of slow- and fast-muscle acetylcholine receptors

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K15348
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 48020:Physiology-related
• Research Institution: Osaka Medical and Pharmaceutical University
• Principal Investigator: Yamashita Manami 大阪医科薬科大学, 医学部, 講師 (80750637)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 筋弛緩剤 / 速筋・遅筋 / アセチルコリン受容体

Outline of Final Research Achievements

In mammals, slow and fast muscles are intermingled within individual muscles. Therefore, many of the assumed functions of slow and fast muscles are based on speculation, and their molecular basis remains unclear. In zebrafish, it has been reported that slow and fast muscles are anatomically distinct, and their acetylcholine receptor subunit compositions are different. It is also known that the muscles used for body movements change during development. We showed here that a classical non-depolarizing muscle relaxant pancuronium inhibits fast muscle fibers at lower concentration compared to slow muscle fibers in zebrafish. We further showed that this difference arises from the different composition of acetylcholine receptors between slow and fast muscle fibers in the neuromuscular junction of zebrafish.

Free Research Field

生理学

Academic Significance and Societal Importance of the Research Achievements

筋弛緩剤は手術等の全身麻酔の際に体動を抑えるために必須である。筋弛緩剤が速筋・遅筋といったすべての骨格筋を同等に効果があるのかはわかっていなかった。今回速筋優位に抑える筋弛緩剤を同定し、そのメカニズムを明らかにしたことにより、今後速筋・遅筋を選択的に抑制する薬剤の開発につながると考えられる。速筋・遅筋選択的な筋弛緩剤が開発されれば、リハビリテーションへの応用も期待される。