Energy expenditure is reduced in preobese 2-day Zucker fa/fa rats.

B. J. Moore, S. J. Armbruster, B. A. Horwitz, Judith S Stern

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


The rate of oxygen consumption was measured in 2-day Zucker preobese (fa/fa), homozygous (Fa/Fa) lean, and lean rats of unknown genotype (Fa/?) over the ambient temperature range of 26-35 degrees C. Significant differences in body mass were found among the three groups at this early age, the preobese pups having the greatest body mass. To account for body mass differences, the oxygen consumption data were expressed in terms of metabolic body size (ml O2 consumed X g body mass-2/3 X h-1). This mass-independent rate of oxygen consumption was significantly lower in the preobese pups than in the homozygous lean (Fa/Fa) pups at both thermoneutral (33-34 degrees C) and cold (26-27 degrees C) ambient temperatures at which, respectively, minimal and maximal rates of oxygen consumption were observed. This reduction in energy expenditure occurs before the establishment of hyperphagia or decreased levels of activity in the preobese pups. These data support the view that attenuated energy expenditure is a significant contributor to the early development of obesity in the Zucker fatty rat and point to the possibility of defective brown adipose tissue-mediated thermogenesis in the preobese pup.

Original languageEnglish (US)
JournalThe American journal of physiology
Issue number2 Pt 2
StatePublished - Aug 1985
Externally publishedYes

ASJC Scopus subject areas

  • Medicine(all)


Dive into the research topics of 'Energy expenditure is reduced in preobese 2-day Zucker fa/fa rats.'. Together they form a unique fingerprint.

Cite this