title: Nociceptin/orphanin FQ peptide in hypothalamic neurones associated with the control of feeding behaviour.
abstract: Nociceptin/orphanin FQ (N/OFQ), an endogenous peptide agonist of the opioid N/OFQ receptor, has been implicated in the regulation of energy balance. In the present study, we have used immunohistochemistry to investigate the cellular localisation and colocalisation of N/OFQ-immunoreactive cell bodies in hypothalamic regions containing neurones producing orexigenic or anorexigenic transmitters. In colchicine-treated rats, N/OFQ immunoreactivity was demonstrated in many cell bodies of the arcuate nucleus (Arc), paraventricular nucleus (PVN) and lateral hypothalamic area (LHA). Double-labelling revealed that N/OFQ was present in some neurones located in the ventrolateral part of the Arc producing pro-opiomelanocortin, as shown by the presence of the anorexigenic peptides alpha-melanocyte-stimulating hormone (alpha-MSH) and cocaine- and amphetamine-regulated transcript and, occasionally, in single neurones of the ventrolateral Arc producing orexigenic agouti-related peptide, but not neuropeptide Y. N/OFQ immunoreactivity was also demonstrated in a few tyrosine hydroxylase- or dynorphin (DYN)-containing neurones in the dorsomedial part of the Arc. In the parvocellular PVN, N/OFQ was demonstrated in some thyrotrophin-releasing hormone- or DYN-, but not corticotrophin-releasing hormone-containing neurones. Most N/OFQ-immunoreactive neurones in the LHA contained orexin- and DYN, but not melanin-concentrating hormone. The results obtained, demonstrating the presence of N/OFQ in some alpha-MSH- and in many orexin-containing neurones, suggest a functional relationship between these neuropeptides and N/OFQ in the control of feeding behaviour and body weight.
authors.affiliation: Department of Neuroscience, The Retzius Laboratory, Karolinska Institutet, Stockholm, Sweden.
authors.forename: N
authors.initials: N
authors.lastname: Maolood
authors.forename: B
authors.initials: B
authors.lastname: Meister
mesh_terms: D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000378:metabolism*; D005247:Feeding Behavior / Q000502:physiology*; D007026:Hypothalamic Area, Lateral / Q000378:metabolism*; D007031:Hypothalamus / Q000378:metabolism; D007150:Immunohistochemistry; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D008297:Male; D009474:Neurons / Q000378:metabolism*; D009479:Neuropeptides / Q000378:metabolism; D018847:Opioid Peptides / Q000378:metabolism*; D000068797:Orexins; D010286:Paraventricular Hypothalamic Nucleus / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D000521:alpha-MSH / Q000378:metabolism; D000097629:Nociceptin
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D018847:Opioid Peptides; D000068797:Orexins; D000521:alpha-MSH; D000097629:Nociceptin