Internal de-synchronization among multiple circadian oscillators.

2015 Fiscal Year Final Research Report

• Project/Area Number: 26861780
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Orthodontics/Pediatric dentistry
• Research Institution: Osaka University
• Principal Investigator: Takasu Nana 大阪大学, 歯学研究科(研究院), 特別研究員(RPD) (30467394)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 概日リズム / 体内時計 / 社会的時差ボケ / 内的脱同調 / 視交叉上核 / 弓状核

Outline of Final Research Achievements

The circadian pacemaker in the suprachiasmatic nucleus (SCN) of the hypothalamus is responsible for controlling behavioral activity rhythms, such as a free running rhythm in constant darkness. There are several circadian oscillators in other brain regions including the arcuate nucleus (ARC). In specific conditions such as food anticipatory activity rhythms in the context of timed restricted feeding, an alternative circadian pace-making system has been assumed by means of circadian oscillators like the SCN. Consequently, an internal de-synchronization might be occurred within a body. We investigated circadian rhythms in the SCN and extra-SCN region of the ARC by analyzing PER2::LUCIFERASE expression in specific regions from wild-type C57BL/6, Cry1－/－, and Cry2－/－ mice. Interestingly, the periods in the ARC of both genotypes were identical to those in the SCN. Moreover, the amplitudes of PER2::LUC rhythms in the ARC of all animals were decreased compared to those in the SCN.

Free Research Field

環境生理学