|
|
|
|
Manuscript received 20 October 1997. Initial reviews completed 4 December 1997. Revision accepted 28 May 1998.
Pennington Biomedical Research Center and * Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70808
Osborne-Mendel (OM) and S5B/Pl rats differ in their sensitivity to develop obesity when fed a high fat (HF) diet; OM rats become obese, whereas S5B/Pl rats remain thin. We have investigated the possibilities that either an impaired leptin response or resistance to leptin action underlies the sensitivity to this form of obesity in OM rats. In Experiment 1, OM and S5B/Pl rats fed a nonpurified diet were killed at d 0 or were fed either a HF (56% fat energy) or a low fat (LF, 10% fat energy) diet for 2 or 7 d. The HF diet increased serum leptin significantly by d 2 to levels that were similar in both rat strains. At 7 d, leptin levels were lower than at d 2 but remained higher than levels in the d 0 control groups. The leptin mRNA:18S RNA ratio in epididymal adipose tissue increased to higher levels in HF-fed OM rats than in S5B/Pl rats fed that diet. However, although the LF diet had no effect in S5B/Pl rats, it increased leptin mRNA levels in epididymal adipose tissue of OM rats compared with the controls fed the nonpurified diet. In Experiment 2, OM and S5B/Pl rats were fed HF or LF diets for 5 wk. At that time, their feeding response to a range of leptin doses (0, 1, 5 or 10 µg) given intracerebroventricularly was tested after overnight food deprivation. There was a similar dose-dependent reduction in energy intake in response to leptin in both OM and S5B/Pl rats. These responses were independent of the diet. The data suggest that the susceptibility of OM rats to HF diet-induced obesity is not related to either a loss of central sensitivity to leptin or a failure to enhance leptin production acutely, although the failure to maintain chronically increased levels of serum leptin could contribute to the obesity.
Key words: leptin, dietary fat, obesity, adipose tissue, rats.
The Journal of Nutrition Vol. 128 No. 10 October 1998,
pp. 1606-1613
Copyright ©1998 by the American Society for Nutritional Sciences
This article has been cited by other articles:
![]() |
B. G. Irani, A. A. Dunn-Meynell, and B. E. Levin Altered Hypothalamic Leptin, Insulin, and Melanocortin Binding Associated with Moderate-Fat Diet and Predisposition to Obesity Endocrinology, January 1, 2007; 148(1): 310 - 316. [Abstract] [Full Text] [PDF] |
||||
![]() |
B Beck Neuropeptide Y in normal eating and in genetic and dietary-induced obesity Phil Trans R Soc B, July 29, 2006; 361(1471): 1159 - 1185. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Zheng, L. M. Patterson, C. B. Phifer, and H.-R. Berthoud Brain stem melanocortinergic modulation of meal size and identification of hypothalamic POMC projections Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2005; 289(1): R247 - R258. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. A. Archer, D. V. Rayner, and J. G. Mercer Hypothalamic Gene Expression Is Altered in Underweight but Obese Juvenile Male Sprague-Dawley Rats Fed a High-Energy Diet J. Nutr., June 1, 2004; 134(6): 1369 - 1374. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. E. Levin, A. A. Dunn-Meynell, M. R. Ricci, and D. E. Cummings Abnormalities of leptin and ghrelin regulation in obesity-prone juvenile rats Am J Physiol Endocrinol Metab, November 1, 2003; 285(5): E949 - E957. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. R. Ricci and B. E. Levin Ontogeny of diet-induced obesity in selectively bred Sprague-Dawley rats Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2003; 285(3): R610 - R618. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. K. Roberts, J. J. Berger, and R. J. Barnard Long-term effects of diet on leptin, energy intake, and activity in a model of diet-induced obesity J Appl Physiol, September 1, 2002; 93(3): 887 - 893. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. M. Madiehe, L. Lin, C. White, H. D. Braymer, G. A. Bray, and D. A. York Constitutive activation of STAT-3 and downregulation of SOCS-3 expression induced by adrenalectomy Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2001; 281(6): R2048 - R2058. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Lin, R. Martin, A. O. Schaffhauser, and D. A. York Acute changes in the response to peripheral leptin with alteration in the diet composition Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2001; 280(2): R504 - R509. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. R. Steinberg and D. J. Dyck Development of leptin resistance in rat soleus muscle in response to high-fat diets Am J Physiol Endocrinol Metab, December 1, 2000; 279(6): E1374 - E1382. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. A Ainslie, J. Proietto, B. C Fam, and A. W Thorburn Short-term, high-fat diets lower circulating leptin concentrations in rats1 Am. J. Clinical Nutrition, February 1, 2000; 71(2): 438 - 442. [Abstract] [Full Text] [PDF] |
||||