Document Detail


The role of corticosterone in supporting migratory lipogenesis in the dark-eyed Junco, Junco hyemalis: a model for central and peripheral regulation.
MedLine Citation:
PMID:  17160885     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The functional role of corticosterone (CORT) in regulating migratory hyperphagia and lipogenesis was investigated in an annual migrant, the dark-eyed junco (Junco hyemalis). Intraperitoneal injections of either dexamethasone (9 microg DXM/500 microL of 5% EtOH in saline, n=10) to inhibit an increase in baseline CORT or saline (5% EtOH, n=9) were given every 48 h for 15 d after transfer from short (10.5L:13.5D) to long (15.5L:8.5D) days. Food intake, body mass, furcular fat deposition scores, and nocturnal migratory activity were recorded for 29 d after photostimulation. Both groups showed the same increase in daily food intake over the study period (DXM=52%, control=41%). Controls began to increase baseline CORT and mass about 2 wk after photostimulation. DXM-treated birds maintained low CORT and did not increase mass or CORT until injections ceased, at which time they gained mass at the same rate shown earlier by controls. DXM-treated birds did not show greater levels of migratory activity despite experiencing an increase in energy intake during the CORT-inhibited period. Collectively, the results support the migration modulation hypothesis, illustrating how an increase in baseline CORT is needed to support the development of migratory condition. We address the apparent conflict with earlier studies on CORT and migratory food intake and propose a model in which migratory hyperphagia is supported by changes in centrally regulated responses to CORT that can occur even if CORT remains low and lipogenesis is regulated predominantly by peripheral mechanisms that require an increase in baseline CORT.
Authors:
R L Holberton; C Morgan Wilson; M J Hunter; W B Cash; C G Sims
Related Documents :
1570805 - The effect of dietary protein intake on glutamine and glutamate nitrogen metabolism in ...
24919545 - Survival of norovirus surrogate on various food-contact surfaces.
19650955 - When, how much and what foods are eaten are related to total daily food intake.
22297045 - Use of mid- and near-infrared spectroscopy to track degradation of bio-based eating ute...
10574515 - Overeating in america: association between restaurant food consumption and body fatness...
11716315 - Do adolescent vitamin-mineral supplement users have better nutrient intakes than nonuse...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.     Date:  2006-11-21
Journal Detail:
Title:  Physiological and biochemical zoology : PBZ     Volume:  80     ISSN:  1522-2152     ISO Abbreviation:  Physiol. Biochem. Zool.     Publication Date:    2007 Jan-Feb
Date Detail:
Created Date:  2006-12-12     Completed Date:  2007-02-16     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  100883369     Medline TA:  Physiol Biochem Zool     Country:  United States    
Other Details:
Languages:  eng     Pagination:  125-37     Citation Subset:  IM    
Affiliation:
Department of Biology, University of Mississippi, Mississippi 38677, USA. rebecca.holberton@maine.edu
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animal Migration*
Animals
Body Weight
Corticosterone / physiology*
Energy Intake
Lipogenesis*
Photoperiod
Songbirds / physiology*
Chemical
Reg. No./Substance:
50-22-6/Corticosterone

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


Previous Document:  The potential role of CO2 in initiation and maintenance of estivation in the land snail Helix lucoru...
Next Document:  Energetic consequences and ecological significance of heterothermy and social thermoregulation in st...