Intracerebroventricular administration of galanin or galanin receptor subtype 1 agonist M617 induces c-Fos activation in central amygdala and dorsomedial hypothalamus.
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.
Blackshear
Alice
A
Department of Psychology, Stony Brook University, Stony Brook, NY 11794-2500, USA.
Yamamoto
Mihoko
M
Anderson
Brenda J
BJ
Holmes
Philip V
PV
Lundström
Linda
L
Langel
Ulo
U
Robinson
John K
JK
D000679:Amygdala / Q000187:drug effects* / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D004302:Dorsomedial Hypothalamic Nucleus / Q000187:drug effects* / Q000378:metabolism; D019004:Galanin / Q000008:administration & dosage / Q000494:pharmacology*; D007150:Immunohistochemistry; D007276:Injections, Intraventricular; D008297:Male; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D044091:Receptor, Galanin, Type 1 / Q000819:agonists*
D016760:Proto-Oncogene Proteins c-fos; D044091:Receptor, Galanin, Type 1; D019004:Galanin