Format

Send to

Choose Destination
Am J Physiol Regul Integr Comp Physiol. 2014 Aug 15;307(4):R465-70. doi: 10.1152/ajpregu.00179.2014. Epub 2014 Jun 18.

Hindbrain nucleus tractus solitarius glucagon-like peptide-1 receptor signaling reduces appetitive and motivational aspects of feeding.

Author information

1
Department of Psychology, University of Pennsylvania, Philadelphia, Pennsylvania amberla@sas.upenn.edu.
2
Department of Psychology, University of Pennsylvania, Philadelphia, Pennsylvania.

Abstract

Central glucagon-like peptide-1 receptor (GLP-1R) signaling reduces food intake by affecting a variety of neural processes, including those mediating satiation, motivation, and reward. While the literature suggests that separable neurons and circuits control these processes, this notion has not been adequately investigated. The intake inhibitory effects of GLP-1R signaling in the hindbrain medial nucleus tractus solitarius (mNTS) have been attributed to interactions with vagally transmitted gastrointestinal satiation signals that are also processed by these neurons. Here, behavioral and pharmacological techniques are used to test the novel hypothesis that the reduction of food intake following mNTS GLP-1R stimulation also results from effects on food-motivated appetitive behaviors. Results show that mNTS GLP-1R activation by microinjection of exendin-4, a long-acting GLP-1R agonist, reduced 1) intake of a palatable high-fat diet, 2) operant responding for sucrose under a progressive ratio schedule of reinforcement and 3) the expression of a conditioned place preference for a palatable food. Together, these data demonstrate that the intake inhibitory effects of mNTS GLP-1R signaling extend beyond satiation and include effects on food reward and motivation that are typically ascribed to midbrain and forebrain neurons.

KEYWORDS:

exendin-4; food intake; glucagon-like peptide-1; motivation; nucleus tractus solitarius; reward

PMID:
24944243
PMCID:
PMC4137150
DOI:
10.1152/ajpregu.00179.2014
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

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