title: Histaminergic modulation of stress-induced analgesia and cognitive dysfunction.
abstract: Physiological stress is known to produce analgesia and memory disruption. A large body of evidence favors the nonopiate mediation of stress-induced analgesia. It is suggested that brain histamine mediates nonopiate analgesia and participates in learning and memory in rodents. Histamine is released during stress, although the nature of histaminergic involvement in stress response is not clearly defined. Therefore, we studied the effect of L-histidine and histamine-receptor antagonists on antinociception and impaired retention induced by immobilization stress. In the present study, immobilization stress produced a naloxone-resistant analgesia that was potentiated by L-histidine and antagonized by pretreatment with the histamine receptor antagonists chlorpheniramine and cimetidine. L-histidine attenuated the memory disruption induced by immobilization stress, which was significantly reversed by chlorpheniramine but not by cimetidine. Thus the involvement of the central histaminergic system, through histamine H1- and H2-receptors, may be speculated in analgesia and cognitive deficit induced by immobilization stress.
authors.affiliation: University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India.
authors.forename: V N
authors.initials: VN
authors.lastname: Paul
authors.forename: K
authors.initials: K
authors.lastname: Chopra
authors.forename: S K
authors.initials: SK
authors.lastname: Kulkarni
mesh_terms: D000698:Analgesia; D000700:Analgesics / Q000494:pharmacology; D000818:Animals; D002744:Chlorpheniramine / Q000494:pharmacology; D002927:Cimetidine / Q000494:pharmacology; D003072:Cognition Disorders / Q000378:metabolism / Q000503:physiopathology / Q000517:prevention & control*; D005260:Female; D018494:Histamine Agents / Q000494:pharmacology*; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D006635:Histamine H2 Antagonists / Q000494:pharmacology; D006636:Histamine Release / Q000187:drug effects; D006639:Histidine / Q000494:pharmacology; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008569:Memory Disorders / Q000378:metabolism / Q000503:physiopathology / Q000517:prevention & control*; D051379:Mice; D009270:Naloxone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D011968:Receptors, Histamine / Q000187:drug effects; D011969:Receptors, Histamine H1 / Q000187:drug effects; D011970:Receptors, Histamine H2 / Q000187:drug effects; D013312:Stress, Physiological / Q000503:physiopathology*
chemical_list: D000700:Analgesics; D018494:Histamine Agents; D006634:Histamine H1 Antagonists; D006635:Histamine H2 Antagonists; D009292:Narcotic Antagonists; D011968:Receptors, Histamine; D011969:Receptors, Histamine H1; D011970:Receptors, Histamine H2; D009270:Naloxone; D002744:Chlorpheniramine; D006639:Histidine; D002927:Cimetidine