Overfeeding-induced weight gain suppresses plasma ghrelin levels in rats

The elevation of plasma ghrelin associated with weight loss has been taken as evidence of a role for ghrelin in the adaptive response to body weight change. However, there has been no clear experimental evidence that circulating ghrelin is suppressed by weight gain. We investigate this issue using a...

Full description

Saved in:
Bibliographic Details
Published in:Journal of endocrinological investigation 2006-11, Vol.29 (10), p.863-868
Main Authors: Williams, D L, Grill, H J, Cummings, D E, Kaplan, J M
Format: Article
Language:English
Subjects:
Adipose Tissue - physiopathology
Animals
Body Weight - physiology
Energy Metabolism - physiology
Ghrelin
Hyperphagia - blood
Hyperphagia - physiopathology
Male
Obesity - blood
Obesity - etiology
Obesity - physiopathology
Peptide Hormones - blood
Rats
Rats, Sprague-Dawley
Weight Gain - physiology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The elevation of plasma ghrelin associated with weight loss has been taken as evidence of a role for ghrelin in the adaptive response to body weight change. However, there has been no clear experimental evidence that circulating ghrelin is suppressed by weight gain. We investigate this issue using a model of involuntary (intra-gastric gavage) overfeeding-induced obesity. Rats were first maintained at normal body weight with 4 daily tube-feedings of liquid diet (2.11 kcal/ml), each delivered at a volume of 9 ml. Gavage volume was then increased to 13 ml/feeding for 2 weeks, during which rats gained 25% of their initial body weight. Fasting plasma ghrelin levels and the response to 9- and 13-ml intra-gastric load sizes were measured during the weight-stable and overfed conditions. We found that: 1) weight gain decreased circulating ghrelin levels; 2) this response could not be attributed to additional food in the gastrointestinal tract; 3) the ghrelin response to nutrient loads was diminished in the obese vs normal-weight conditions. Having discounted diet composition and differences in gastric contents at the time of blood sampling, the decrease in ghrelin levels with overfeeding can be unambiguously attributed to physiological correlates of weight gain.
ISSN:0391-4097
1720-8386
DOI:10.1007/BF03349188