title: Histamine H(3) receptor modulates nociception in a rat model of cholestasis.
abstract: Cholestasis is associated with changes including analgesia. The histaminergic system regulates pain perception. The involvement of histamine H(3) receptors in modulation of nociception in a model of elevated endogenous opioid tone, cholestasis, was investigated in this study using immepip and thioperamide as selective H(3) receptor agonist and antagonist respectively. Cholestasis was induced by ligation of main bile duct using two ligatures and transsection the duct between them. Cholestatic rats had increased tail-flick latencies (TFLs) compared to non-cholestatics. Administration of immepip (5 and 30mg/kg) and thioperamide (10 and 20mg/kg) to the cholestatic groups significantly increased and decreased TFLs compared to the saline treated cholestatic group. Immepip antinociception in cholestatic animals was attenuated by co-administration of naloxone. Immepip and thioperamide injections into non-cholestatic animals did not alter TFLs. At the doses used here, none of the drugs impaired motor coordination, as revealed by the rotarod test. The present data show that the histamine H(3) receptor system may be involved in the regulation of nociception during cholestasis in rats.
authors.affiliation: Bu-Ali Sina University, School of Basic Sciences, Department of Biology, 65178-33391 Hamedan, Iran. p.hasanein@basu.ac.ir
authors.forename: Parisa
authors.initials: P
authors.lastname: Hasanein
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001652:Bile Ducts / Q000502:physiology; D002779:Cholestasis / Q000150:complications / Q000503:physiopathology*; D017442:Histamine Agonists / Q000494:pharmacology; D054828:Histamine H3 Antagonists / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D008297:Male; D009270:Naloxone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D010146:Pain / Q000209:etiology / Q000503:physiopathology*; D010147:Pain Measurement / Q000187:drug effects; D010880:Piperidines / Q000494:pharmacology; D004856:Postural Balance / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time; D018100:Receptors, Histamine H3 / Q000502:physiology*
chemical_list: D017442:Histamine Agonists; D054828:Histamine H3 Antagonists; D007093:Imidazoles; D009292:Narcotic Antagonists; D010880:Piperidines; D018100:Receptors, Histamine H3; C085755:4-(1H-imidazol-4-ylmethyl)piperidine; D009270:Naloxone; C052075:thioperamide