title: Long-term ovariectomy enhances anxiety and depressive-like behaviors in mice submitted to chronic unpredictable stress.
abstract: Ovarian hormones exert anti-depressive and anxiolytic actions. In this study we have analyzed the effects of ovariectomy on the development of anxiety and depression-like behaviors and on cell proliferation in the hippocampus of mice submitted to chronic unpredictable stress. Animals submitted to stress 4 months after ovariectomy showed a significant increase in immobility behavior in the forced swimming test compared to animals submitted to stress 2 weeks after ovariectomy. In addition, long-term ovariectomy resulted in a significant decrease on the time spent in the open arms in the elevated plus-maze test compared to control animals. Stress did not significantly affect cell proliferation in the hilus of the dentate gyrus. However, ovariectomy resulted in a significant decrease in cell proliferation. These results indicate that long-term deprivation of ovarian hormones enhances the effect of chronic unpredictable stress on depressive- and anxiety-like behaviors in mice. Therefore, a prolonged deprivation of ovarian hormones may represent a risk factor for the development of depressive and anxiety symptoms after the exposure to stressful experiences.
authors.affiliation: Instituto Cajal, CSIC, Avenida Doctor Arce 37, Madrid, Spain.
authors.forename: Natalia
authors.initials: N
authors.lastname: Lagunas
authors.forename: Isabel
authors.initials: I
authors.lastname: Calmarza-Font
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Diz-Chaves
authors.forename: Luis M
authors.initials: LM
authors.lastname: Garcia-Segura
mesh_terms: D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology; D001007:Anxiety / Q000209:etiology* / Q000517:prevention & control; D001522:Behavior, Animal / Q000502:physiology*; D002908:Chronic Disease; D003863:Depression / Q000209:etiology* / Q000517:prevention & control; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D018782:Maze Learning / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D010052:Ovariectomy / Q000009:adverse effects*; D013315:Stress, Psychological / Q000150:complications* / Q000503:physiopathology* / Q000523:psychology; D013550:Swimming / Q000502:physiology; D013997:Time Factors; D015854:Up-Regulation
chemical_list: D014151:Anti-Anxiety Agents; D004958:Estradiol