title: A pharmacological evidence of positive association between mouse intermale aggression and brain serotonin metabolism.
abstract: The neurotransmitter serotonin (5-HT) is involved in the regulation of mouse intermale aggression. Previously, it was shown that intensity of mouse intermale aggression was positively associated with activity of the key enzyme of 5-HT synthesis - tryptophan hydroxylase 2 (TPH2) in mouse brain. The aim of the present study was to investigate the effect of pharmacological activation or inhibition of 5-HT synthesis in the brain on intermale aggression in two mouse strains differing in the TPH2 activity: C57BL/6J (B6, high TPH2 activity, high aggressiveness) and CC57BR/Mv (BR, low TPH2 activity, low aggressiveness). Administration of 5-HT precursor L-tryptophan (300 mg/kg, i.p.) to BR mice significantly increased the 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) levels in the midbrain as well as the number of attacks and their duration in the resident-intruder test. And vice versa, administration of TPH2 inhibitor p-chlorophenylalanine (pCPA) (300 mg/kg, i.p., for 3 consecutive days) to B6 mice dramatically reduced the 5-HT and 5-HIAA contents in brain structures and attenuated the frequency and the duration of aggressive attacks. At the same time, L-tryptophan or pCPA did not influence the percentage of aggressive mice and the attack latency reflecting the threshold of aggressive reaction. This result indicated that the intensity of intermale aggression, but not the threshold of aggressive reaction is positively dependent on 5-HT metabolism in mouse brain.
authors.affiliation: Department of Behavioral Neurogenomics, Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Science, Lavrentyeva av. 10, Novosibirsk 630090, Russia. akulikov@ngs.ru
authors.forename: A V
authors.initials: AV
authors.lastname: Kulikov
authors.forename: D V
authors.initials: DV
authors.lastname: Osipova
authors.forename: V S
authors.initials: VS
authors.lastname: Naumenko
authors.forename: E
authors.initials: E
authors.lastname: Terenina
authors.forename: P
authors.initials: P
authors.lastname: Mormède
authors.forename: N K
authors.initials: NK
authors.lastname: Popova
mesh_terms: D000374:Aggression / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D001921:Brain / Q000033:anatomy & histology / Q000187:drug effects* / Q000201:enzymology*; D004563:Electrochemistry; D004791:Enzyme Inhibitors / Q000009:adverse effects; D005106:Exploratory Behavior / Q000187:drug effects; D010134:Fenclonine / Q000009:adverse effects; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011110:Polymorphism, Genetic / Q000235:genetics; D012701:Serotonin / Q000378:metabolism*; D014364:Tryptophan / Q000494:pharmacology; D014365:Tryptophan Hydroxylase / Q000235:genetics / Q000378:metabolism*
chemical_list: D004791:Enzyme Inhibitors; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D014364:Tryptophan; C487802:Tph2 protein, mouse; D014365:Tryptophan Hydroxylase; D010134:Fenclonine