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The onset of daily torpor is regulated by the same low body mass in lean mice and in mice with diet-induced obesity

Effects of reducing body mass on body core temperature and locomotor activity of mice originally kept on conventional rodent diet (Group-1) were compared to those made obese by feeding them a high-fat diet (Group-2), both groups being kept at a cool ambient temperature. Based on earlier experience,...

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Autores principales: Solymár, Margit, Pétervári, Erika, Balaskó, Márta, Szelényi, Zoltán
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Taylor & Francis 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4843878/
https://www.ncbi.nlm.nih.gov/pubmed/27227011
http://dx.doi.org/10.1080/23328940.2015.1014250
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author Solymár, Margit
Pétervári, Erika
Balaskó, Márta
Szelényi, Zoltán
author_facet Solymár, Margit
Pétervári, Erika
Balaskó, Márta
Szelényi, Zoltán
author_sort Solymár, Margit
collection PubMed
description Effects of reducing body mass on body core temperature and locomotor activity of mice originally kept on conventional rodent diet (Group-1) were compared to those made obese by feeding them a high-fat diet (Group-2), both groups being kept at a cool ambient temperature. Based on earlier experience, threshold torpor core temperature of 31° was chosen as the endpoint to decreasing body mass. It was hypothesized that the onset of this hypothermia develops in obese mice only when their body mass approaches a similar low body mass as in lean mice. Mice in Group-1 maintained nocturnal core temperature but developed marked daytime hypothermia of 30–31°C with their body mass approaching 20 g by this time. Mice in Group-2 could maintain normal circadian temperature rhythm for 3 weeks before similar daytime hypothermia started to develop while their body mass dropped also to about 20 g. Mice belonging to Group-1 or Group-2 could regain original body mass after re-feeding with the original diet within 2 days or 5 weeks, respectively. In the course of the development of daily torpor, nighttime normothermia was accompanied by progressive increases in locomotor activity in both groups of mice. It is concluded that in mice a marked fall of daytime body core temperature is only induced when a similar low critical body mass is reached, irrespective of the initial body mass. In other words, in both groups of mice the nutritional state determines the threshold for the thermoregulatory change during torpor.
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spelling pubmed-48438782016-05-25 The onset of daily torpor is regulated by the same low body mass in lean mice and in mice with diet-induced obesity Solymár, Margit Pétervári, Erika Balaskó, Márta Szelényi, Zoltán Temperature (Austin) Research Paper Effects of reducing body mass on body core temperature and locomotor activity of mice originally kept on conventional rodent diet (Group-1) were compared to those made obese by feeding them a high-fat diet (Group-2), both groups being kept at a cool ambient temperature. Based on earlier experience, threshold torpor core temperature of 31° was chosen as the endpoint to decreasing body mass. It was hypothesized that the onset of this hypothermia develops in obese mice only when their body mass approaches a similar low body mass as in lean mice. Mice in Group-1 maintained nocturnal core temperature but developed marked daytime hypothermia of 30–31°C with their body mass approaching 20 g by this time. Mice in Group-2 could maintain normal circadian temperature rhythm for 3 weeks before similar daytime hypothermia started to develop while their body mass dropped also to about 20 g. Mice belonging to Group-1 or Group-2 could regain original body mass after re-feeding with the original diet within 2 days or 5 weeks, respectively. In the course of the development of daily torpor, nighttime normothermia was accompanied by progressive increases in locomotor activity in both groups of mice. It is concluded that in mice a marked fall of daytime body core temperature is only induced when a similar low critical body mass is reached, irrespective of the initial body mass. In other words, in both groups of mice the nutritional state determines the threshold for the thermoregulatory change during torpor. Taylor & Francis 2015-02-13 /pmc/articles/PMC4843878/ /pubmed/27227011 http://dx.doi.org/10.1080/23328940.2015.1014250 Text en © 2015 The Author(s). Published with license by Taylor & Francis Group, LLC http://creativecommons.org/licenses/by-nc/3.0/ This is an Open Access article distributed under the terms of the Creative Commons Attribution-Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. The moral rights of the named author(s) have been asserted.
spellingShingle Research Paper
Solymár, Margit
Pétervári, Erika
Balaskó, Márta
Szelényi, Zoltán
The onset of daily torpor is regulated by the same low body mass in lean mice and in mice with diet-induced obesity
title The onset of daily torpor is regulated by the same low body mass in lean mice and in mice with diet-induced obesity
title_full The onset of daily torpor is regulated by the same low body mass in lean mice and in mice with diet-induced obesity
title_fullStr The onset of daily torpor is regulated by the same low body mass in lean mice and in mice with diet-induced obesity
title_full_unstemmed The onset of daily torpor is regulated by the same low body mass in lean mice and in mice with diet-induced obesity
title_short The onset of daily torpor is regulated by the same low body mass in lean mice and in mice with diet-induced obesity
title_sort onset of daily torpor is regulated by the same low body mass in lean mice and in mice with diet-induced obesity
topic Research Paper
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4843878/
https://www.ncbi.nlm.nih.gov/pubmed/27227011
http://dx.doi.org/10.1080/23328940.2015.1014250
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