spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

First published online September 11, 2009
Journal of Experimental Biology 212, 3060-3067 (2009)
Published by The Company of Biologists 2009
doi: 10.1242/jeb.029835
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Google Scholar
Right arrow Articles by Rønning, B.
Right arrow Articles by Bech, C.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Rønning, B.
Right arrow Articles by Bech, C.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

Food restriction in young Japanese quails: effects on growth, metabolism, plasma thyroid hormones and mRNA species in the thyroid hormone signalling pathway

Bernt Rønning1,*, Anne S. Mortensen1, Børge Moe1,2, Olivier Chastel3, Augustine Arukwe1,{dagger} and Claus Bech1,{dagger}

1 Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
2 Norwegian Institute for Nature Research (NINA), Division of Arctic Ecology, NO-9296 Tromsø, Norway
3 Centre d'Étude Biologiques de Chizé (CEBC), Centre National de la Recherche Scientifique, 79360 Villiers en Bois, France

* Author for correspondence (bernt.ronning{at}bio.ntnu.no)

Accepted 29 June 2009

Young birds, in their post-natal growth period, may reduce their growth and metabolism when facing a food shortage. To examine how such responses can be mediated by endocrine-related factors, we exposed Japanese quail chicks to food restriction for either 2 days (age 6–8 days) or 5 days (age 6–11 days). We then measured growth and resting metabolic rate (RMR), and circulating 3,3',5-triiodo-L-thyronine (T3) and 3,5,3',5'-tetraiodothyronine (T4) levels as well as expression patterns of genes involved in growth (insulin-like growth factor-I: IGF-I) and thyroid hormone signalling (thyroid-stimulating hormone-β: TSHβ, type II iodothyronine deiodinase: D2, thyroid hormone receptors isoforms: TR{alpha} and TRβ). The food-restricted chicks receiving a weight-maintenance diet showed reductions in structural growth and RMR. Plasma levels of both T3 and T4 were reduced in the food-restricted birds, and within the 5 days food-restricted group there was a positive correlation between RMR and T3. IGF-I mRNA showed significantly higher abundance in the liver of ad libitum fed birds at day 8 compared with food-restricted birds. In the brain, TSHβ mRNA level tended to be lower in food-restricted quails on day 8 compared with controls. Furthermore, TR{alpha} expression was lower in the brain of food-restricted birds at day 8 compared with birds fed ad libitum. Interestingly, brain D2 mRNA was negatively correlated with plasma T3 levels, tending to increase with the length of food restriction. Overall, our results show that food restriction produced significant effects on circulating thyroid hormones and differentially affected mRNA species in the thyroid hormone signalling pathway. Thus, we conclude that the effects of food restriction observed on growth and metabolism were partly mediated by changes in the endocrine-related factors investigated.


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?




© The Company of Biologists Ltd 2009