title: The effect of serotonergic system on nociceptin/orphanin FQ induced food intake in chicken.
abstract: The present study was designed to examine the effects of intracerebroventricular injection of para-chlorophenylalanine (PCPA) (cerebral serotonin depletive), fluoxetine (selective serotonin reuptake inhibitor), 8-OH-DPAT (5-HT1A autoreceptor agonist) and SB 242084 (5-HT2c receptor antagonist) on nociceptin/orphanin FQ (N/OFQ) induced feeding response in chickens. A guide cannula was surgically implanted into the lateral ventricle of chickens. Before the experiments, 3-h fasting periods had been given to all experimental birds. In experiment 1, chickens were injected with PCPA (1.5 μg) followed by an N/OFQ injection (16 nmol) intracerebroventricularly. In experiment 2, birds received fluoxetine (10 μg) prior to the injection of N/OFQ. In experiment 3, chickens were administered with N/OFQ after the 8-OH-DPAT administration (15.25 nmol). In experiment 4, birds were injected with SB 242084 (1.5 μg) followed by an N/OFQ injection. Cumulative food intake was measured at 3 h post injection. The results of this study show that N/OFQ increases food intake in broiler cockerels (P < 0.05) and that this effect is amplified by pretreatment with PCPA and SB 242084 in an additive manner (P < 0.05). The effect of N/OFQ is not changed by pretreatment with 8-OH-DPAT (P > 0.05). Furthermore, the stimulatory effect of N/OFQ on food intake was significantly attenuated by pretreatment with fluoxetine. These results suggest that N/OFQ induced hyperphagia is mediated by serotonergic mechanisms, and possibly imply an interaction between N/OFQ and the serotonergic system (via 5-HT2C receptors) on food intake in chickens.
authors.affiliation: Department of Physiology, Faculty of Veterinary Medicine, University of Tehran, 14155-6453, Tehran, Iran. zendedel@ut.ac.ir
authors.forename: Morteza
authors.initials: M
authors.lastname: Zendehdel
authors.forename: Kasra
authors.initials: K
authors.lastname: Mokhtarpouriani
authors.forename: Vahab
authors.initials: V
authors.lastname: Babapour
authors.forename: Ali
authors.initials: A
authors.lastname: Baghbanzadeh
authors.forename: Maryam
authors.initials: M
authors.lastname: Pourrahimi
authors.forename: Shahin
authors.initials: S
authors.lastname: Hassanpour
mesh_terms: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000631:Aminopyridines / Q000494:pharmacology; D000818:Animals; D002645:Chickens; D005247:Feeding Behavior / Q000187:drug effects*; D010134:Fenclonine / Q000494:pharmacology; D005473:Fluoxetine / Q000494:pharmacology; D007211:Indoles / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D018847:Opioid Peptides / Q000008:administration & dosage / Q000494:pharmacology*; D044405:Receptor, Serotonin, 5-HT2C / Q000502:physiology; D012701:Serotonin / Q000502:physiology*; D058830:Serotonin 5-HT2 Receptor Antagonists / Q000494:pharmacology; D012702:Serotonin Antagonists / Q000494:pharmacology*; D000097629:Nociceptin
chemical_list: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000631:Aminopyridines; D010134:Fenclonine; D005473:Fluoxetine; D007211:Indoles; D018847:Opioid Peptides; D044405:Receptor, Serotonin, 5-HT2C; D012701:Serotonin; D058830:Serotonin 5-HT2 Receptor Antagonists; D012702:Serotonin Antagonists; D000097629:Nociceptin; C107820:6-chloro-5-methyl-1-((2-(2-methylpyrid-3-yloxy)pyrid-5-yl)carbamoyl)indoline