Feeding effects of hypothalamic injection of melanocortin 4 receptor ligands.
It has been reported that intraventricular administration of the melanocortin 4 receptor (MC4-R) agonist MT II and antagonist SHU9119 alter food intake. We found that MT II and SHU9119 have extremely potent effects on feeding when injected in the paraventricular nucleus (PVN), a site where MC4-R gene expression is very high. Our finding provides direct evidence that MC4-R signaling is important in mediating food intake and that melanocortin neurons in the PVN exert a tonic inhibition of feeding behavior. Chronic disruption of this inhibitory signal is a possible explanation of the agouti-obesity syndrome.
Giraudo
S Q
SQ
Department of Medicine, University of Minnesota, Minneapolis, USA.
Billington
C J
CJ
Levine
A S
AS
D000818:Animals; D004435:Eating / Q000187:drug effects*; D008024:Ligands; D008297:Male; D009074:Melanocyte-Stimulating Hormones / Q000494:pharmacology*; D009479:Neuropeptides / Q000494:pharmacology; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects / Q000502:physiology*; D010456:Peptides, Cyclic / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D044105:Receptor, Melanocortin, Type 4; D018043:Receptors, Corticotropin / Q000819:agonists* / Q000037:antagonists & inhibitors*; D000521:alpha-MSH / Q000031:analogs & derivatives / Q000494:pharmacology
D008024:Ligands; D009479:Neuropeptides; D010456:Peptides, Cyclic; D044105:Receptor, Melanocortin, Type 4; D018043:Receptors, Corticotropin; C096783:acetyl-norleucyl-aspartyl-histidyl-phenylalanyl-arginyl-beta-methyltryptophyl-lysinamide, cyclic (2-7)-peptide; C103272:SHU 9119; D000521:alpha-MSH; D009074:Melanocyte-Stimulating Hormones