title: Neurochemical, hormonal, and behavioral effects of chronic unpredictable stress in the rat.
abstract: The high comorbidity of anxiety and depression suggests a potential degree of commonality in their etiologies. The chronic unpredictable stress (CUS) model effectively replicates depressive-like phenotypes; however, the ability of CUS to produce anxiety-like behaviors has not been adequately addressed. Using the CUS paradigm (2 stressors per day for 10 days) in adult Sprague-Dawley rats we identified behavioral, hormonal, and neurochemical changes one day after the cessation of treatment. Stress attenuated weight gain throughout the study and increased locomotor activity one day after treatment, but had no effect on anxiety-behavior as measured by the elevated plus maze. In addition, plasma corticosterone levels were positively correlated with hypothalamic serotonin (5-HT) activity one day after stress treatment as determined by the ratio of the metabolite 5-hydroxyindoleacetic acid (5-HIAA) to the parent compound (5-HIAA/5-HT ratio). These data suggest behavioral phenotypes associated with depression, but not comorbid anxiety, emerge in the immediate period after cessation of stress and that stress related physiology is related to 5-HT activity in the hypothalamus.
authors.affiliation: Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI 48201, USA.
authors.forename: Brittney M
authors.initials: BM
authors.lastname: Cox
authors.forename: Fares
authors.initials: F
authors.lastname: Alsawah
authors.forename: Peter C
authors.initials: PC
authors.lastname: McNeill
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Galloway
authors.forename: Shane A
authors.initials: SA
authors.lastname: Perrine
mesh_terms: D000818:Animals; D001007:Anxiety / Q000503:physiopathology; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D001921:Brain / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002908:Chronic Disease; D003345:Corticosterone / Q000097:blood*; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism*; D007031:Hypothalamus / Q000378:metabolism / Q000473:pathology; D008297:Male; D018782:Maze Learning / Q000502:physiology; D009043:Motor Activity / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000378:metabolism; D013223:Statistics as Topic; D013315:Stress, Psychological / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D015430:Weight Gain / Q000502:physiology
chemical_list: D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D003345:Corticosterone