Intracerebroventricular administration of galanin or galanin receptor subtype 1 agonist M617 induces c-Fos activation in central amygdala and dorsomedial hypothalamus

Peptides. 2007 May;28(5):1120-4. doi: 10.1016/j.peptides.2007.01.015. Epub 2007 Feb 1.

Abstract

The neuropeptide galanin and galanin receptors are widespread throughout cortical, limbic and midbrain areas implicated in reward, learning/memory, pain, drinking and feeding. While many studies have shown that galanin produces a variety of presynaptic and post-synaptic responses, work studying the effects of galanin on neural activation is limited. The present study examined patterns of c-Fos immunoreactivity resulting from intracerebroventricular administration of galanin versus saline injection in awake rats. An initial comprehensive qualitative survey was conducted to identify regions of high c-Fos expression followed up with quantitative analysis. Galanin induced a significant increase in c-Fos levels relative to saline-treated controls in dorsomedial hypothalamus and in the central nucleus of the amygdala. This pattern of activation was also produced by galanin receptor type 1 agonist M617. The present findings confirm that galanin upregulates c-Fos activation in hypothalamic nuclei, and supports roles for galanin in central amygdala-mediated regulation of stress-responses, food intake, and Pavlovian conditioning.

MeSH terms

  • Amygdala / drug effects*
  • Amygdala / metabolism
  • Analysis of Variance
  • Animals
  • Dorsomedial Hypothalamic Nucleus / drug effects*
  • Dorsomedial Hypothalamic Nucleus / metabolism
  • Galanin / administration & dosage
  • Galanin / pharmacology*
  • Immunohistochemistry
  • Injections, Intraventricular
  • Male
  • Proto-Oncogene Proteins c-fos / metabolism*
  • Rats
  • Rats, Sprague-Dawley
  • Receptor, Galanin, Type 1 / agonists*

Substances

  • Proto-Oncogene Proteins c-fos
  • Receptor, Galanin, Type 1
  • Galanin