Document Detail

Entrainment of temperature and activity rhythms to restricted feeding in orexin knock out mice.
MedLine Citation:
PMID:  18343358     Owner:  NLM     Status:  MEDLINE    
Ablation of the SCN, an established circadian clock, does not abolish food entrainment, suggesting that the food-entrainable oscillator (FEO) must lie outside the SCN. Typically, animals show anticipatory locomotor activity and rise in core body temperature under the influence of the FEO. Signals from the FEO would, therefore, converge onto arousal neurons so that the animal might forage for food. In the present study, we investigate whether the neuropeptide orexin, which has been linked to arousal, might transduce the arousal signal. Orexin-knockout (orexin-KO) and wildtype (WT) mice (both C57BL/6J derived) were implanted with MiniMitter transmitters that recorded core body temperature and activity (12 h LD cycle). After a week of ad-libitum feeding, the mice were given access to food for 4 h (ZT 4-8) for nine days followed by 2-days of fasting. When orexin-KO mice were placed in a restricted feeding schedule, both core body temperature and activity entrained to the feeding schedule. In these mice gross locomotor activity was severely blunted during the nine day period of restricted feeding (-79.4+/-6.3%) from the WT, but they showed an increase in core body temperature in anticipation to the meal time similar to the WT mice. There was no difference in the amount of food intake between the genotypes. We conclude that orexin is not required for entrainment of activity and temperature to a restricted feeding schedule, but is required for the robust expression of gross locomotor activity in anticipation of the scheduled feeding.
Satvinder Kaur; Stephen Thankachan; Suraiya Begum; Carlos Blanco-Centurion; Takeshi Sakurai; Masashi Yanagisawa; Priyattam J Shiromani
Related Documents :
21676728 - Phenotypic flexibility and physiological tradeoffs in the feeding and growth of marine ...
6411488 - The effect of digitoxose on feeding behavior.
19096078 - Characterization of energetic efficiency in adult broiler breeder hens.
18400998 - Laboratory observations on the feeding behavior and feeding rate of the nemertean proce...
14635808 - Leaf pubescence mediates the abundance of non-prey food and the density of the predator...
20630488 - Technological trends, global market, and challenges of bio-ethanol production.
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural; Research Support, U.S. Gov't, Non-P.H.S.     Date:  2008-02-21
Journal Detail:
Title:  Brain research     Volume:  1205     ISSN:  0006-8993     ISO Abbreviation:  Brain Res.     Publication Date:  2008 Apr 
Date Detail:
Created Date:  2008-04-18     Completed Date:  2008-07-22     Revised Date:  2011-05-12    
Medline Journal Info:
Nlm Unique ID:  0045503     Medline TA:  Brain Res     Country:  Netherlands    
Other Details:
Languages:  eng     Pagination:  47-54     Citation Subset:  IM    
West Roxbury VA Medical Center and Harvard Medical School, 1400 VFW Parkway, West Roxbury, MA 02132, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Arousal / physiology
Caloric Restriction*
Fasting / physiology
Intracellular Signaling Peptides and Proteins / genetics*,  physiology*
Mice, Inbred C57BL
Mice, Knockout
Motor Activity / physiology*
Neuropeptides / genetics*,  physiology*
Signal Transduction / physiology
Grant Support
Reg. No./Substance:
0/Intracellular Signaling Peptides and Proteins; 0/Neuropeptides; 0/orexins

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Effects of omni-directional noise-exposure during hearing onset and age on auditory spatial resoluti...
Next Document:  Influence of volume reduction and cryopreservation methodologies on quality of thawed umbilical cord...