Adrenalectomy lowers the body weight set-point in rats.
In order to evaluate the impact of a complete depletion of glucocorticoids on rats' body weight set-point, rats were adrenalectomized, and their set-points were estimated before, and after surgery. Body weight set-points were obtained from a quantitative behavioral method based on the rats' food-hoarding response to weight deficit. In addition, body fat contents were measured in vivo using a total body electrical conductivity analyzer (TOBEC). The hoarding of food showed that adrenalectomized rats had significantly lower body weight set-points than the sham-operated controls (337 +/- 11 g vs. 385 +/- 8 g) and were also significantly lighter. TOBEC measurements showed that the sham-operated control rats had a higher body fat content than the adrenalectomized rats ( 16.7 +/- 1.1% vs. 10.2 +/- 1.2%). The present study demonstrates that adrenalectomy lowers the body weight set-point in rats, suggesting that the concentrations of glucocorticoid hormones, and in turn, the hypothalamic corticotrophin releasing hormone (CRH) participates in the adjustment of the body weight set-point.
Gosselin
C
C
Département de physiologie, Faculté de médecine, Université Laval, Québec, Canada.
Cabanac
M
M
D000315:Adrenalectomy; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D001835:Body Weight / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley