title: The Female Encounter Test: A Novel Method for Evaluating Reward-Seeking Behavior or Motivation in Mice.
abstract: BACKGROUND
  Reduced motivation is an important marker of psychiatric disorders, including depression. We describe the female encounter test, a novel method of evaluating reward-seeking behavior in mice.
  
  
  METHODS
  The test apparatus consists of three open chambers, formed with partitions that allow the animal to move freely from one chamber to another. A test male mouse is habituated in the apparatus, and subsequently a female and male mouse are introduced into a wire-mesh box in the left and right chamber, respectively. The time the test male mouse spends in the female or male area is measured for 10 min.
  
  
  RESULTS
  All six strains of mice tested showed a significant preference for female encounters. The preference was observed in 7-30-week-old mice. The preference was blocked by castration of the resident male test mouse, and was not affected by the phase of the menstrual cycle of the female intruder. The preference was impaired in mouse models of depression, including social isolation-reared, corticosterone-treated, and lipopolysaccharide-treated mice. The impairment was alleviated by fluvoxamine in isolation-reared and lipopolysaccharide-treated mice, and it was improved by the metabotropic glutamate 2/3 receptor antagonist LY341495 in corticosterone-treated mice. Encounter with a female, but not male, mouse increased c-Fos expression in the nucleus accumbens shell of test male mice. Furthermore, both the preference and encounter-induced increases in c-Fos expression were blocked by dopamine D1 and D2 receptor antagonists.
  
  
  CONCLUSIONS
  These findings indicate that motivation in adult male mice can be easily evaluated by quantitating female encounters.
authors.affiliation: Laboratory of Medicinal Pharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Ago, Mr Hasebe, Ms Nishiyama, Mr Oka, Mr Onaka, Drs Takuma, and Matsuda); Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Hashimoto); United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Suita, Osaka, Japan (Drs Hashimoto and Matsuda); Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan (Dr Takuma).
authors.forename: Yukio
authors.initials: Y
authors.lastname: Ago
authors.affiliation: Laboratory of Medicinal Pharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Ago, Mr Hasebe, Ms Nishiyama, Mr Oka, Mr Onaka, Drs Takuma, and Matsuda); Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Hashimoto); United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Suita, Osaka, Japan (Drs Hashimoto and Matsuda); Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan (Dr Takuma).
authors.forename: Shigeru
authors.initials: S
authors.lastname: Hasebe
authors.affiliation: Laboratory of Medicinal Pharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Ago, Mr Hasebe, Ms Nishiyama, Mr Oka, Mr Onaka, Drs Takuma, and Matsuda); Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Hashimoto); United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Suita, Osaka, Japan (Drs Hashimoto and Matsuda); Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan (Dr Takuma).
authors.forename: Saki
authors.initials: S
authors.lastname: Nishiyama
authors.affiliation: Laboratory of Medicinal Pharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Ago, Mr Hasebe, Ms Nishiyama, Mr Oka, Mr Onaka, Drs Takuma, and Matsuda); Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Hashimoto); United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Suita, Osaka, Japan (Drs Hashimoto and Matsuda); Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan (Dr Takuma).
authors.forename: Satoshi
authors.initials: S
authors.lastname: Oka
authors.affiliation: Laboratory of Medicinal Pharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Ago, Mr Hasebe, Ms Nishiyama, Mr Oka, Mr Onaka, Drs Takuma, and Matsuda); Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Hashimoto); United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Suita, Osaka, Japan (Drs Hashimoto and Matsuda); Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan (Dr Takuma).
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Onaka
authors.affiliation: Laboratory of Medicinal Pharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Ago, Mr Hasebe, Ms Nishiyama, Mr Oka, Mr Onaka, Drs Takuma, and Matsuda); Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Hashimoto); United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Suita, Osaka, Japan (Drs Hashimoto and Matsuda); Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan (Dr Takuma).
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Hashimoto
authors.affiliation: Laboratory of Medicinal Pharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Ago, Mr Hasebe, Ms Nishiyama, Mr Oka, Mr Onaka, Drs Takuma, and Matsuda); Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Hashimoto); United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Suita, Osaka, Japan (Drs Hashimoto and Matsuda); Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan (Dr Takuma).
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Takuma
authors.affiliation: Laboratory of Medicinal Pharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Ago, Mr Hasebe, Ms Nishiyama, Mr Oka, Mr Onaka, Drs Takuma, and Matsuda); Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (Dr Hashimoto); United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Suita, Osaka, Japan (Drs Hashimoto and Matsuda); Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan (Dr Takuma). matsuda@phs.osaka-u.ac.jp.
authors.forename: Toshio
authors.initials: T
authors.lastname: Matsuda
mesh_terms: D000596:Amino Acids / Q000494:pharmacology; D000818:Animals; D018687:Antidepressive Agents, Second-Generation / Q000494:pharmacology; D002369:Castration; D002755:Choice Behavior / Q000187:drug effects / Q000502:physiology; D003345:Corticosterone; D003866:Depressive Disorder / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology; D004195:Disease Models, Animal; D004867:Equipment Design; D030762:Estrous Cycle; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005260:Female; D016666:Fluvoxamine / Q000494:pharmacology; D008070:Lipopolysaccharides; D008297:Male; D051379:Mice / Q000502:physiology / Q000523:psychology*; D009042:Motivation; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism; D011581:Psychological Tests; D012201:Reward; D012919:Social Behavior; D012934:Social Isolation; D014966:Xanthenes / Q000494:pharmacology
chemical_list: D000596:Amino Acids; D018687:Antidepressive Agents, Second-Generation; D018691:Excitatory Amino Acid Antagonists; C114624:LY 341495; D008070:Lipopolysaccharides; D014966:Xanthenes; D016666:Fluvoxamine; D003345:Corticosterone
keywords: Depression model; dopamine; encounter test; nucleus accumbens; sexual motivation