Nutritional State Influences Nociceptin/Orphanin FQ Peptide Receptor Expression in the Dorsal Raphe Nucleus
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Psychology
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Agonists of the nociceptin/orphanin FQ (N/OFQ) peptide (NOP) receptor stimulate food intake. Concordantly, neuroanatomical localization of NOP receptor mRNA has revealed it to be highly expressed in brain regions associated with the regulation of energy balance. However, the specific mechanisms and neurochemical pathways through which physiological N/OFQ influences appetite are not well understood. To investigate this, we examined nutritional state-associated changes in NOP receptor mRNA levels throughout the rostrocaudal extent of the rat brain using in situ hybridization histochemistry (ISHH) and quantitative densitometry analysis. We observed a significant downregulation of NOP receptor mRNA in the dorsal raphe nucleus (DRN) of fasted rats compared to free-feeding rats. In contrast, no difference in NOP receptor mRNA expression was observed in the supraoptic, parventricular, ventromedial, arcuate or dorsomedial nuclei of the hypothalamus, the red nucleus, the locus coeruleus or the hypoglossal nucleus in the fasted or fed state. These data suggest that the endogenous N/OFQ system is responsive to changes in energy balance and that NOP receptors specifically within the DRN may be physiologically relevant to N/OFQ's effects on appetite.
Diaz-Rua A, Chivite M, Comesana S, Conde-Sieira M, Soengas J Front Physiol. 2022; 13:800218.
PMID: 35299666 PMC: 8921556. DOI: 10.3389/fphys.2022.800218.
Mendez I, Maidment N, Murphy N Behav Pharmacol. 2016; 27(6):516-27.
PMID: 27100061 PMC: 4965319. DOI: 10.1097/FBP.0000000000000240.
Nociceptin receptor antagonist SB 612111 decreases high fat diet binge eating.
Hardaway J, Jensen J, Kim M, Mazzone C, Sugam J, DiBerto J Behav Brain Res. 2016; 307:25-34.
PMID: 27036650 PMC: 4896639. DOI: 10.1016/j.bbr.2016.03.046.
Battistoni S, Kloting I, Cifani C, Massi M, Polidori C Genes Nutr. 2011; 6(2):197-202.
PMID: 21484154 PMC: 3092911. DOI: 10.1007/s12263-010-0189-3.
Distinct physiological and behavioural functions for parental alleles of imprinted Grb10.
Garfield A, Cowley M, Smith F, Moorwood K, Stewart-Cox J, Gilroy K Nature. 2011; 469(7331):534-8.
PMID: 21270893 PMC: 3031026. DOI: 10.1038/nature09651.