Regulatory mechanisms of esophageal striated muscle motility by the central and peripheral systems

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K08122
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Integrative animal science
• Research Institution: Gifu University
• Principal Investigator: Shiina Takahiko 岐阜大学, 応用生物科学部, 准教授 (90362178)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 食道 / 横紋筋 / 平滑筋 / 一酸化窒素 / カリウムチャネル / プリン受容体

Outline of Final Research Achievements

The aim of this study was to clarify central and peripheral regulation on esophageal striated muscle motility in mammals. I characterized peristaltic motility using a novel in vivo method in rats. A balloon-tipped catheter was placed in the esophagus of a rat anesthetized with urethane to induce esophageal peristalsis. A nitric oxide synthase inhibitor abolished the induction of esophageal peristalsis, which suggests that nitric oxide plays essential roles in the induction of esophageal peristalsis. On the other hand, an isolated segment of the rat esophagus was placed in an organ bath and mechanical responses were recorded. Pharmacological and morphological studies indicated that purinergic receptors and potassium channels contribute to motor regulation of esophageal muscle motility peripherally. These findings provide novel insights into the regulatory mechanisms of esophageal striated muscle motility.

Free Research Field

獣医学

Academic Significance and Societal Importance of the Research Achievements

ほ乳類の食道筋層は、小腸や大腸と異なり、一部または全長にわたって横紋筋で構成されている。一方、食道は摂取した食物を胃まで運搬する役割を持つことから、食道横紋筋も小腸や大腸の平滑筋と同様に蠕動運動を担っている。蠕動運動は、筋の収縮のみならず、適切な弛緩も必要とすることから、食道横紋筋が「収縮」とともに「弛緩（収縮の抑制）」する制御機構の解明は重要である。食道以外の消化管（胃、小腸、大腸）では、中枢性制御に加えて、内在神経系などによる末梢性（局所）制御が発達している。本研究の意義は、食道横紋筋運動の中枢性および末梢性制御機構の一旦を明らかにしたことにある。