Parabrachial CGRP Neurons Control Meal Termination

Cell Metab. 2016 May 10;23(5):811-20. doi: 10.1016/j.cmet.2016.04.006.

Abstract

The lateral parabrachial nucleus is a conduit for visceral signals that cause anorexia. We previously identified a subset of neurons located in the external lateral parabrachial nucleus (PBel) that express calcitonin gene-related peptide (CGRP) and inhibit feeding when activated by illness mimetics. We report here that in otherwise normal mice, functional inactivation of CGRP neurons markedly increases meal size, with meal frequency being reduced in a compensatory manner, and renders mice insensitive to the anorexic effects of meal-related satiety peptides. Furthermore, CGRP neurons are directly innervated by orexigenic hypothalamic AgRP neurons, and photostimulation of AgRP fibers supplying the PBel delays satiation by inhibiting CGRP neurons, thereby contributing to AgRP-driven hyperphagia. By establishing a role for CGRP neurons in the control of meal termination and as a downstream mediator of feeding elicited by AgRP neurons, these findings identify a node in which hunger and satiety circuits interact to control feeding behavior.

MeSH terms

  • Agouti-Related Protein / metabolism
  • Animals
  • Anorexia / metabolism
  • Anorexia / pathology
  • Calcitonin Gene-Related Peptide / metabolism*
  • Central Amygdaloid Nucleus / metabolism
  • Cholecystokinin
  • Feeding Behavior*
  • Glucagon-Like Peptide-1 Receptor / agonists
  • Glucagon-Like Peptide-1 Receptor / metabolism
  • Hyperphagia / metabolism
  • Hyperphagia / pathology
  • Leptin
  • Mice, Inbred C57BL
  • Neurons / metabolism
  • Parabrachial Nucleus / metabolism*
  • Satiety Response

Substances

  • Agouti-Related Protein
  • Glucagon-Like Peptide-1 Receptor
  • Leptin
  • Cholecystokinin
  • Calcitonin Gene-Related Peptide