Proteins activate satiety-related neuronal pathways in the brainstem and hypothalamus of rats

J Nutr. 2008 Jun;138(6):1172-8. doi: 10.1093/jn/138.6.1172.

Abstract

Our objective was to study the relationship between the satiety induced by high-protein meals and the activation of brain areas involved in the onset of satiety. In rats, we used immunohistochemistry to monitor brain centers activated by a meal by receiving information from the gastrointestinal tract or via humoral pathways. In the nucleus of the solitary tract (NTS), the acute or chronic intake of high-protein meals led to increased activation of the noradrenergic/adrenergic neurons involved in cholecystokinin-induced satiety. In the arcuate nucleus of the hypothalamus, the melanocortin pathway was also more strongly activated after the acute or chronic intake of high-protein meals. Moreover, the glucagon-like peptide 1 pathway arising from the NTS, which is triggered, among other behaviors, during nonphysiological anorexia, was not activated by high-protein meals, supporting the lack of aversive behavior associated with this diet. Taken together, these results show that the ability of high-protein meals to inhibit food intake occurs alongside the activation, in nutrient-sensitive brain areas, of several specific neuronal populations involved in satiety.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain Stem / cytology*
  • Brain Stem / drug effects
  • Dietary Proteins / administration & dosage
  • Dietary Proteins / pharmacology*
  • Eating / drug effects
  • Hypothalamus / cytology*
  • Hypothalamus / drug effects
  • Male
  • Neurons / drug effects*
  • Neurons / physiology
  • Rats
  • Rats, Wistar
  • Satiation / drug effects*
  • Signal Transduction / drug effects*

Substances

  • Dietary Proteins