Histaminergic H1 receptors mediate L-histidine-induced anxiety in elevated plus-maze test in mice.
The central histaminergic system is reported to mediate behavioural, hormonal and physiological homeostasis of living organisms. Recent reports indicate its prominent role in various neurobehavioural disorders such as depression and psychosis. This study evaluated the effect of activation of the central histaminergic system in anxiety-like conditions, using the elevated plus-maze test in mice, and elucidated the role of different histaminergic receptors mediating such effects. Peripheral administration of L-histidine (L-His), in a dose-dependent manner, significantly decreased the exploration time in open arms and number of entries into open arms without modifying the number of entries into closed arms of the elevated plus-maze, indicating anxiogenesis. Further, such effects of central histamine were significantly attenuated, in a dose-dependent manner, by pretreatment with pyrilamine (H1 receptor antagonist). Pretreatment with either zolantidine (H2 receptor antagonist) or thioperamide (H3 receptor antagonist), however, failed to attenuate the L-His-induced anxiogenesis. Our results indicate that anxiogenic effects of central histaminergic system appear to be mediated prominently by activation of H1 receptors.
Kumar
Kuchibhotla Vijaya
KV
Neuropharmacology Unit, Division of Pharmacology, Central Drug Research Institute, Lucknow, India.
Krishna
Devarakonda Rama
DR
Palit
Gautam
G
D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology; D001007:Anxiety / Q000139:chemically induced* / Q000523:psychology*; D052160:Benzothiazoles / Q000494:pharmacology; D003975:Diazepam / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006633:Histamine Antagonists / Q000494:pharmacology; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D006635:Histamine H2 Antagonists / Q000494:pharmacology; D006639:Histidine; D008297:Male; D051379:Mice; D050198:Phenoxypropanolamines / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D011738:Pyrilamine / Q000494:pharmacology; D011968:Receptors, Histamine / Q000187:drug effects / Q000502:physiology; D011969:Receptors, Histamine H1 / Q000187:drug effects*; D018100:Receptors, Histamine H3 / Q000187:drug effects
D014151:Anti-Anxiety Agents; D052160:Benzothiazoles; D006633:Histamine Antagonists; D006634:Histamine H1 Antagonists; D006635:Histamine H2 Antagonists; D050198:Phenoxypropanolamines; D010880:Piperidines; D011968:Receptors, Histamine; D011969:Receptors, Histamine H1; D018100:Receptors, Histamine H3; D006639:Histidine; D011738:Pyrilamine; C052075:thioperamide; C055302:zolantidine; D003975:Diazepam