Elucidation of swallowing suppression mechanism during mastication and central control mechanism of swallowing

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K11492
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Functional basic dentistry
• Research Institution: The Nippon Dental University
• Principal Investigator: Satoh Yoshihide 日本歯科大学, 新潟生命歯学部, 教授 (20287775)
• Research Collaborator: INOUE Makoto ; TSUJIMURA Takanori
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 嚥下 / 顎運動 / 扁桃体

Outline of Final Research Achievements

The rhythmic jaw movements were induced by repetitive electrical stimulation of the dorsomedial part of the central amygdaloid nucleus in the rat. The number of swallowing reflexes evoked by electrical stimulation of the superior laryngeal nerve was significantly reduced when rhythmic jaw movements were occurring compared to when jaw movements were not occurring. In addition, the time from the onset of superior laryngeal nerve stimulation to the first swallowing was significantly prolonged when rhythmic jaw movement was induced compared to when jaw movement was not occurring.
From these results, it is suggested that suppression of the swallowing reflex during jaw movements is caused by inhibition of the nucleus of the solitary tract which is the swallowing center.

Free Research Field

口腔生理学

Academic Significance and Societal Importance of the Research Achievements

大脳辺縁系に存在する扁桃体の電気刺激により、咀嚼運動に似たリズミックな顎運動が誘発された。そして、リズミックな顎運動が生じているときは、顎運動が生じていないときに比べ、嚥下反射の回数は有意に減少した。従って咀嚼を行っている間は、嚥下が生じないように脳内で調節されていることが示唆された。
本研究は、咀嚼と嚥下の関係およびその制御機構解明の一助となり、誤嚥性肺炎の予防ための基礎研究といえる。