Premium
Stress‐induced hyperthermia is not mediated by interscapular brown adipose tissue in mice
Author(s) -
Vianna Daniel Machado Luiz,
Carrive Pascal
Publication year - 2011
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.25.1_supplement.1044.1
Subject(s) - brown adipose tissue , propranolol , thermogenesis , hyperthermia , open field , medicine , endocrinology , saline , adipose tissue , chemistry
Psychological stress increases body temperature through a sympathetic mechanism. Brown adipose tissue (BAT) produces heat in response to sympathetic activation. Stress‐induced hyperthermia (SIH) is a widely used anxiety indicator. We thus sought to verify if SIH can be attributed to BAT thermogenesis in mice. Eight C57BL/6 mice received injections of 20 mg/kg dl‐propranolol or saline and were placed in either an open field or 4°C enclosure for 30 min. Infrared pictures were taken each minute to record interscapular (TiScap), lumbar (TBack) and tail (TTail) temperatures. Propranolol reduced SIH observed during open field exposure (p<0.01), as indicated by TiScap and TBack, but did not change the 2°C difference between these two variables (p>0.05), which is a measure of BAT thermogenesis. There was no observable effect of propranolol on behaviour, as animals remained active throughout the test. In contrast, the difference between TiScap and TBack was increased by 2°C during cold exposure, and this increase was abolished after propranolol (p<0.0005), indicating BAT thermogenesis during this challenge. Just as rats exposed to conditioned fear, mice exposed to an open field display SIH that is not mediated by BAT. Supported by the National Health and Medical Research Council of Australia.