Cold acclimation-associated changes in brown adipose tissue do not necessarily indicate an increase of nonshivering thermogenesis in C57BL/6J mice

Mark I. Talan, Sergei A Kirov, Lori A. Clow, Nadejda A. Kosheleva

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

We have reported previously that a cold acclimation procedure (3-hr partial restraint at 6°C, repeated 3 times at 2-week intervals) usually improves the cold tolerance of adult C57BL/6J mice. Those mice that did not improve their cold tolerance had lower cold-induced sympathetic nervous outflow to the interscapular brown adipose tissue (IBAT), suggesting a failure in the mechanisms of nonshivering thermogenesis. To understand the origin of this failure, this study was intended to measure nonshivering thermogenesis in mice that did not improve their cold tolerance after the cold acclimation procedure. After being subjected 3 times to a partial restraint at 6°C, mice were anesthetized with urethane, immobilized with vecuronium bromide, and placed on artificial ventilation. The VO2 and VCO2 in expired air were measured and metabolic heat production (MHP) was calculated while body temperature was artificially lowered to 7.5°C below control level. In a separate group of mice, the total amount and concentration of mitochondrial uncoupling protein, thermogenin (UCP), in IBAT was measured immediately after completion of the cold-acclimation procedure. The concentration and the amount of UCP in the mitochondria of IBAT was significantly higher in all mice that had been presented to the cold acclimation procedure, regardless of its outcome, than in mice that had never been exposed to an environment below room temperature (NAIVE). MHP increased significantly during body cooling in all mice. However, MHP before and during cold stimulation in mice that did not improve their cold tolerance as a result of the cold-acclimation procedure was significantly lower than the MHP of animals in which cold tolerance was improved, and was not different from MHP of the NAIVE group. Therefore, in mice in which cold tolerance did not improve after repeated cord exposure, the anatomical and biochemical changes in brown adipose tissue typical of cold acclimation were not associated with a cold-induced increase in MHP. We infer that the expression of UCP in brown adipose tissue is a necessary, but not sufficient, attribute of cold acclimation. Cold acclimation, measured as increased cold tolerance, occurs only if synthesis of UCP in BAT is associated with an increased cold-induced response of the sympathetic nervous system.

Original languageEnglish (US)
Pages (from-to)1285-1289
Number of pages5
JournalPhysiology and Behavior
Volume60
Issue number5
DOIs
StatePublished - Jan 1 1996
Externally publishedYes

Fingerprint

Brown Adipose Tissue
Thermogenesis
Acclimatization
Inbred C57BL Mouse
Vecuronium Bromide

Keywords

  • Adaptation
  • Body temperature
  • Brown adipose tissue
  • Cold tolerance
  • Heat production
  • Mitochondria
  • Rodents
  • Temperature regulation
  • Thermogenin
  • Uncoupling protein

ASJC Scopus subject areas

  • Experimental and Cognitive Psychology
  • Behavioral Neuroscience

Cite this

Cold acclimation-associated changes in brown adipose tissue do not necessarily indicate an increase of nonshivering thermogenesis in C57BL/6J mice. / Talan, Mark I.; Kirov, Sergei A; Clow, Lori A.; Kosheleva, Nadejda A.

In: Physiology and Behavior, Vol. 60, No. 5, 01.01.1996, p. 1285-1289.

Research output: Contribution to journalArticle

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