title: Anxiogenic effect of naltrexone in social interaction test in rats.
abstract: OBJECTIVE
  To study the anxiogenic effect of naltrexone (Nal) on the emotional state of rats.
  
  
  METHODS
  The duration of active interaction was measured in the social interaction test in rats.
  
  
  RESULTS
  Without influence on the locomotor activity, Nal (0.1-50 mg.kg-1) dose- and time-dependently decreased the duration of active interaction, which was antagonized by morphine (5 mg.kg-1) or fenclonine (Fen, 150 mg.kg-1 x 3 d) and was enhanced by 5-hydroxytryptophan (5-HTP, 50 mg.kg-1).
  
  
  CONCLUSIONS
  Nal produced anxiety via its blockade of opioid receptors; central opioidergic neurons were involved in the regulation of anxiety through their tonic inhibitions in serotonergic neurons.
authors.affiliation: Institute of Pharmacology & Toxicology, Academy of Military Medical Sciences, Beijing, China.
authors.forename: H T
authors.initials: HT
authors.lastname: Zhang
authors.forename: Z M
authors.initials: ZM
authors.lastname: Xu
authors.forename: Z P
authors.initials: ZP
authors.lastname: Luo
authors.forename: B Y
authors.initials: BY
authors.lastname: Qin
mesh_terms: D000819:Animal Communication; D000818:Animals; D001522:Behavior, Animal; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D009271:Naltrexone / Q000494:pharmacology*; D009292:Narcotic Antagonists / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D009292:Narcotic Antagonists; D009271:Naltrexone