Leptin responsiveness in chronically decerebrate rats

Ruth Babette Harris, Timothy J. Bartness, Harvey J. Grill

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

Peripheral infusions of physiological doses of leptin decrease body fat mass, but it is not known whether this results from direct effects on peripheral tissue or activation of central leptin receptors. In this study, we infused chronically decerebrate (CD) rats, in which the forebrain was surgically isolated from the caudal brainstem, with 60 μg leptin/d or PBS for 14 d from ip mini-osmotic pumps. The CD rats were tube fed an amount of food equivalent to the intake of ad libitum-fed intact controls or 75% of this amount to account for their reduced energy expenditure. Control rats fed ad libitum or tube fed 75, 100, or 125% of their ad libitum intake also were peripherally infused with leptin or PBS. CD rats had a lower serum testosterone, energy expenditure, and lean body mass compared with controls but had increased levels of adiponectin and leptin and were obese. Leptin increased body fat and decreased energy expenditure during the light period in 100%-fed CD rats, but not 75%-fed CD rats. Leptin decreased body fat of ad libitum- and 100%-fed but not 75%-fed or 125%-fed intact controls. Energy expenditure did not change in any control group. These results show that leptin can change body fat independent of a change in food intake or energy expenditure, that the forebrain normally prevents leptin from inhibiting energy expenditure through mechanisms initiated in the caudal brainstem or peripheral tissues, and that the leptin response in both intact and CD rats is determined by the energy status of the animal.

Original languageEnglish (US)
Pages (from-to)4623-4633
Number of pages11
JournalEndocrinology
Volume148
Issue number10
DOIs
StatePublished - Oct 1 2007

Fingerprint

Leptin
Energy Metabolism
Adipose Tissue
Prosencephalon
Brain Stem
Leptin Receptors
Adiponectin
Testosterone
Eating
Light
Food
Control Groups
Serum

ASJC Scopus subject areas

  • Endocrinology

Cite this

Leptin responsiveness in chronically decerebrate rats. / Harris, Ruth Babette; Bartness, Timothy J.; Grill, Harvey J.

In: Endocrinology, Vol. 148, No. 10, 01.10.2007, p. 4623-4633.

Research output: Contribution to journalArticle

Harris, Ruth Babette ; Bartness, Timothy J. ; Grill, Harvey J. / Leptin responsiveness in chronically decerebrate rats. In: Endocrinology. 2007 ; Vol. 148, No. 10. pp. 4623-4633.
@article{78f81a89c81040c580aa71b411afa7ab,
title = "Leptin responsiveness in chronically decerebrate rats",
abstract = "Peripheral infusions of physiological doses of leptin decrease body fat mass, but it is not known whether this results from direct effects on peripheral tissue or activation of central leptin receptors. In this study, we infused chronically decerebrate (CD) rats, in which the forebrain was surgically isolated from the caudal brainstem, with 60 μg leptin/d or PBS for 14 d from ip mini-osmotic pumps. The CD rats were tube fed an amount of food equivalent to the intake of ad libitum-fed intact controls or 75{\%} of this amount to account for their reduced energy expenditure. Control rats fed ad libitum or tube fed 75, 100, or 125{\%} of their ad libitum intake also were peripherally infused with leptin or PBS. CD rats had a lower serum testosterone, energy expenditure, and lean body mass compared with controls but had increased levels of adiponectin and leptin and were obese. Leptin increased body fat and decreased energy expenditure during the light period in 100{\%}-fed CD rats, but not 75{\%}-fed CD rats. Leptin decreased body fat of ad libitum- and 100{\%}-fed but not 75{\%}-fed or 125{\%}-fed intact controls. Energy expenditure did not change in any control group. These results show that leptin can change body fat independent of a change in food intake or energy expenditure, that the forebrain normally prevents leptin from inhibiting energy expenditure through mechanisms initiated in the caudal brainstem or peripheral tissues, and that the leptin response in both intact and CD rats is determined by the energy status of the animal.",
author = "Harris, {Ruth Babette} and Bartness, {Timothy J.} and Grill, {Harvey J.}",
year = "2007",
month = "10",
day = "1",
doi = "10.1210/en.2006-1565",
language = "English (US)",
volume = "148",
pages = "4623--4633",
journal = "Endocrinology",
issn = "0013-7227",
publisher = "The Endocrine Society",
number = "10",

}

TY - JOUR

T1 - Leptin responsiveness in chronically decerebrate rats

AU - Harris, Ruth Babette

AU - Bartness, Timothy J.

AU - Grill, Harvey J.

PY - 2007/10/1

Y1 - 2007/10/1

N2 - Peripheral infusions of physiological doses of leptin decrease body fat mass, but it is not known whether this results from direct effects on peripheral tissue or activation of central leptin receptors. In this study, we infused chronically decerebrate (CD) rats, in which the forebrain was surgically isolated from the caudal brainstem, with 60 μg leptin/d or PBS for 14 d from ip mini-osmotic pumps. The CD rats were tube fed an amount of food equivalent to the intake of ad libitum-fed intact controls or 75% of this amount to account for their reduced energy expenditure. Control rats fed ad libitum or tube fed 75, 100, or 125% of their ad libitum intake also were peripherally infused with leptin or PBS. CD rats had a lower serum testosterone, energy expenditure, and lean body mass compared with controls but had increased levels of adiponectin and leptin and were obese. Leptin increased body fat and decreased energy expenditure during the light period in 100%-fed CD rats, but not 75%-fed CD rats. Leptin decreased body fat of ad libitum- and 100%-fed but not 75%-fed or 125%-fed intact controls. Energy expenditure did not change in any control group. These results show that leptin can change body fat independent of a change in food intake or energy expenditure, that the forebrain normally prevents leptin from inhibiting energy expenditure through mechanisms initiated in the caudal brainstem or peripheral tissues, and that the leptin response in both intact and CD rats is determined by the energy status of the animal.

AB - Peripheral infusions of physiological doses of leptin decrease body fat mass, but it is not known whether this results from direct effects on peripheral tissue or activation of central leptin receptors. In this study, we infused chronically decerebrate (CD) rats, in which the forebrain was surgically isolated from the caudal brainstem, with 60 μg leptin/d or PBS for 14 d from ip mini-osmotic pumps. The CD rats were tube fed an amount of food equivalent to the intake of ad libitum-fed intact controls or 75% of this amount to account for their reduced energy expenditure. Control rats fed ad libitum or tube fed 75, 100, or 125% of their ad libitum intake also were peripherally infused with leptin or PBS. CD rats had a lower serum testosterone, energy expenditure, and lean body mass compared with controls but had increased levels of adiponectin and leptin and were obese. Leptin increased body fat and decreased energy expenditure during the light period in 100%-fed CD rats, but not 75%-fed CD rats. Leptin decreased body fat of ad libitum- and 100%-fed but not 75%-fed or 125%-fed intact controls. Energy expenditure did not change in any control group. These results show that leptin can change body fat independent of a change in food intake or energy expenditure, that the forebrain normally prevents leptin from inhibiting energy expenditure through mechanisms initiated in the caudal brainstem or peripheral tissues, and that the leptin response in both intact and CD rats is determined by the energy status of the animal.

UR - http://www.scopus.com/inward/record.url?scp=34748864673&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34748864673&partnerID=8YFLogxK

U2 - 10.1210/en.2006-1565

DO - 10.1210/en.2006-1565

M3 - Article

C2 - 17615147

AN - SCOPUS:34748864673

VL - 148

SP - 4623

EP - 4633

JO - Endocrinology

JF - Endocrinology

SN - 0013-7227

IS - 10

ER -