title: Chronic mild stress-induced changes of risk assessment behaviors in mice are prevented by chronic treatment with fluoxetine but not diazepam.
abstract: As an important part of risk-related defensive behavior and central element of anxiety, risk assessment in rodents is particularly sensitive to psychosocial stress and may consequently influence the following decision-making and behavioral output. In this study, using a mouse-test battery, we evaluated the possible impacts of chronic mild stress (CMS) on risk assessment behaviors and action selections. For non-stressed control animals, a close relationship between risk assessment and choice behavior was observed in EPM and LDT. For stressed animals, however, 5 weeks of CMS exposure not only increased risk assessment behaviors, but also abolished the correlations between risk assessment and action selection. Pharmacological intervention with GABA-A receptor modulator diazepam (0.25-4 mg/kg) blocked the alterations of conventional spatiotemporal behaviors in response to CMS, but had no effect on the CMS-induced risk assessment behavioral changes. In contrast, 4-weeks of chronic treatment with fluoxetine (4-20mg/kg), a selective serotonin reuptake inhibitor, not only ameliorated the CMS-affected risk-assessment behaviors, but also restored the CMS-impaired correlations between risk assessment and decision making-related action selection. The present findings may shed new light on the better understanding of emotional reactivity and decision making under stressful situations. These results also indicate a differential pharmacological sensitivity in CMS-affected emotional response and risk-assessment behaviors.
authors.affiliation: Liaoning Key Laboratory of Biotechnology and Molecular Drug Research and Development, Liaoning Normal University, Dalian 116081, China; Department of Pharmacy, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China.
authors.forename: Che
authors.initials: C
authors.lastname: Wang
authors.affiliation: School of Foreign Languages, Liaoning Normal University, Dalian 116029, China.
authors.forename: Min
authors.initials: M
authors.lastname: Li
authors.affiliation: Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Morsani College of Medicine, University of South Florida, Tampa, FL 33613, USA.
authors.forename: Darrell
authors.initials: D
authors.lastname: Sawmiller
authors.affiliation: Blood Center of Dalian, Dalian 116001, China.
authors.forename: Yaxin
authors.initials: Y
authors.lastname: Fan
authors.affiliation: School of Humanities and Social Sciences, Dalian University of Technology, Dalian 116023, China.
authors.forename: Yinghua
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Morsani College of Medicine, University of South Florida, Tampa, FL 33613, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Tan
authors.affiliation: School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Yiwei
authors.initials: Y
authors.lastname: Ren
authors.affiliation: School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, China; Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Morsani College of Medicine, University of South Florida, Tampa, FL 33613, USA. Electronic address: lisong_spu2005@yahoo.com.
authors.forename: Song
authors.initials: S
authors.lastname: Li
mesh_terms: D000818:Animals; D014151:Anti-Anxiety Agents / Q000008:administration & dosage*; D001522:Behavior, Animal; D002908:Chronic Disease; D003345:Corticosterone / Q000097:blood; D003975:Diazepam / Q000008:administration & dosage*; D005473:Fluoxetine / Q000008:administration & dosage*; D008297:Male; D051379:Mice; D018570:Risk Assessment; D017367:Selective Serotonin Reuptake Inhibitors / Q000008:administration & dosage*; D013315:Stress, Psychological / Q000517:prevention & control*
chemical_list: D014151:Anti-Anxiety Agents; D003345:Corticosterone; D003975:Diazepam; D005473:Fluoxetine; D017367:Selective Serotonin Reuptake Inhibitors
keywords: Chronic mild stress; Decision making; Risk assessment; Serotonin; γ-Aminobutyric acid