Thioperamide, a histamine H3 receptor antagonist, suppresses NPY-but not dynorphin A-induced feeding in rats.
Whether or not neuropeptide Y (NPY)-induced feeding in rats is influenced by the histaminergic system in the brain was investigated by intracerebroventricular (i.c.v.) administration of a selective histamine H3 receptor antagonist prior to i.c.v. administration of NPY. NPY (10 microg/10 microl) strongly induced feeding in sated rats during the light phase of the day. Dynorphin A1-17 (10 microg/10 microl), a kappa-opioid agonist, and rat pancreatic polypeptide (rPP, 30 microg/10 microl) also stimulated ingestive behavior in sated rats, but food intake in both cases was less than that induced by NPY. Thioperamide maleate, a specific histamine H3 receptor antagonist (408.5 microg/10 microl) reduced the feeding response to NPY by 52% (P < 0.0001), but not to dynorphin A1-17 and rPP. Thioperamide at i.c.v. doses of 40.8-408.5 microg/10 microl had no effect on food intake in sated rats. These results suggest that the thioperamide may have a specific effect on NPY receptor-mediated neuronal systems related to feeding.
Itoh
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E
Pharmaceutical Research Dept., Ube Research Laboratory, UBE Industries Ltd., Yamaguchi, Japan. 28946u@ube-ind.co.jp
Fujimiya
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M
Inui
A
A
D000818:Animals; D004399:Dynorphins / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D004435:Eating / Q000187:drug effects* / Q000502:physiology; D006633:Histamine Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D009478:Neuropeptide Y / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D010191:Pancreatic Polypeptide / Q000008:administration & dosage / Q000494:pharmacology / Q000502:physiology; D019894:Peptide YY / Q000008:administration & dosage / Q000494:pharmacology / Q000502:physiology; D010880:Piperidines / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D018100:Receptors, Histamine H3 / Q000187:drug effects* / Q000502:physiology; D017473:Receptors, Opioid, kappa / Q000819:agonists
D006633:Histamine Antagonists; D009478:Neuropeptide Y; D010880:Piperidines; D018100:Receptors, Histamine H3; D017473:Receptors, Opioid, kappa; D019894:Peptide YY; D010191:Pancreatic Polypeptide; D004399:Dynorphins; C052075:thioperamide