Format

Send to

Choose Destination
Am J Physiol Regul Integr Comp Physiol. 2011 Nov;301(5):R1267-80. doi: 10.1152/ajpregu.00314.2011. Epub 2011 Aug 17.

"Liking" and "wanting" of sweet and oily food stimuli as affected by high-fat diet-induced obesity, weight loss, leptin, and genetic predisposition.

Author information

1
Neurobiology of Nutrition Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA.

Abstract

Cross-sectional studies in both humans and animals have demonstrated associations between obesity and altered reward functions at the behavioral and neural level, but it is unclear whether these alterations are cause or consequence of the obese state. Reward behaviors were quantified in male, outbred Sprague-Dawley (SD) and selected line obesity-prone (OP) and obesity-resistant (OR) rats after induction of obesity by high-fat diet feeding and after subsequent loss of excess body weight by chronic calorie restriction. As measured by the brief access lick and taste-reactivity paradigms, both obese SD and OP rats "liked" low concentrations of sucrose and corn oil less, but "liked" the highest concentrations more, compared with lean rats, and this effect was fully reversed by weight loss in SD rats. Acute food deprivation was unable to change decreased responsiveness to low concentrations but eliminated increased responsiveness to high concentrations in obese SD rats, and leptin administration in weight-reduced SD rats shifted concentration-response curves toward that seen in the obese state in the brief access lick test. "Wanting" and reinforcement learning as assessed in the incentive runway and progressive ratio lever-pressing paradigms was paradoxically decreased in both obese (compared with lean SD rats) and OP (compared with OR rats). Thus, reversible, obesity-associated, reduced "liking" and "wanting" of low-calorie foods in SD rats suggest a role for secondary effects of the obese state on reward functions, while similar differences between select lines of OP and OR rats before induction of obesity indicate a genetic component.

PMID:
21849633
PMCID:
PMC3213949
DOI:
10.1152/ajpregu.00314.2011
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Atypon Icon for PubMed Central
Loading ...
Support Center