The mechanism of photic input transmission in response to light and dark environmental changes in the suprachiasmatic nucleus.

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K07234
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 48010:Anatomy-related
• Research Institution: Kindai University
• Principal Investigator: Nagano Mamoru 近畿大学, 医学部, 准教授 (80155960)
• Co-Investigator(Kenkyū-buntansha): 鯉沼 聡 近畿大学, 医学部, 講師 (10340770) ; 筋野 貢 近畿大学, 医学部, 助教 (30460843)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 視交叉上核 / 光同調 / 時差症候群

Outline of Final Research Achievements

We have elucidated the inter-cellular and inter-regional synchronization system within each region of the suprachiasmatic nucleus (SCN), the center of the internal clock, and the mechanism of light input transmission in response to changes in light and dark environments. We found that light-dark changes cause not only desynchronization between light- and non-light-responsive regions but also interregional desynchronization in the non-photoresponsive region in the SCN. In addition, we found that the longer circadian rhythm of the rostral region appears to entrain the circadian rhythm in the caudal region in the SCN.

Free Research Field

体内時計

Academic Significance and Societal Importance of the Research Achievements

本研究成果は、時差症候群が生じるのかという疑問に対して、体内時計の中枢である視交叉上核における単に光反応領域と非光反応領域間の脱同調のみならず、非光反応領域内においても領域間の脱同調が生じることを明らかにしたもので、時差症候群の原因解明および解消法の早期開発に繋がるものと考える。また、時差症候群の早期解消にとどまらず、体内時計の明暗環境への適応システムの解明に繋がり、リズム障害治療に大いに役立つとともにシフトワーカーの生活習慣病の治療薬などの開発につながるものとして期待される。