2012 Fiscal Year Final Research Report

Ghrelin, a feeding related peptide, and circadian entrainment to the restricted feeding schedule in CS mice

Research Project

Project/Area Number	22590222
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Environmental physiology (including Physical medicine and Nutritional physiology)
Research Institution	University of Fukui
Principal Investigator	ABE Hiroshi 福井大学, 医学部, 教授 (80201896)
Project Period (FY)	2010 – 2012
Keywords	生物時計 / グレリン
Research Abstract	The circadian clock in CS mice entrains to restricted feeding schedule (RF). Behavioral rhythm and clock gene rhythms in the supurachiasmatic nucleus (SCN, a central oscillator in the circadian clock system) of CS mice show clear entrainment to RF (food entrainment). To investigate the mechanisms of RF entrainment in CS mice, present study was designed to clarify the role of ghrelin, which is a peptide closely related to feeding behavior, in the food entrainment in CS mice. Plasma ghrelin concentration levels in RF mice were increased prior to feeding time, while there were no rhythmic changes in ad lib feeding mice. Periodic ghrelin administration induced no changes in behavioral freerunning rhythms under DD. These results indicate t hat ghrelin is not a major cue for food entrainment of circadian clock in the CS mice . The present results suggest that ghrelin might have a role in the food-entrainable oscillator which regulates food anticipatory activity under RF.