title: High levels of estradiol disrupt conditioned place preference learning, stimulus response learning and reference memory but have limited effects on working memory.
abstract: The present study investigated the effects of high levels of estradiol in female rats on four different radial arm maze tasks: the hippocampus-dependent spatial working-reference memory task; the prefrontal cortex-hippocampus dependent delayed win-shift task; the striatum-dependent cued win-stay task; and the amygdala-dependent conditioned place preference task. Ovariectomized female rats were injected daily with either 10 microg of estradiol benzoate or sesame oil vehicle approximately 4 h prior to testing. In Experiment 1, treatment with estradiol disrupted learning on the spatial working-reference memory task by increasing the number of reference memory errors to reach criterion. In Experiment 2, treatment with estradiol had no significant effect on the delayed win-shift task. In Experiment 3, treatment with estradiol resulted in impaired performance on a striatum-dependent cued win-stay task. In Experiment 4, treatment with estradiol impaired the acquisition of a conditioned place-preference task. Taken together these findings suggest that high levels of estradiol inhibit reference memory, stimulus response learning, and amygdala-dependent appetitive conditioning while having little effect on working memory.
authors.affiliation: Department of Psychology, The University of British Columbia, 2136 West Mall, Vancouver B.C., Canada V6T 1Z4. lgalea@psych.ubc.ca
authors.forename: L A
authors.initials: LA
authors.lastname: Galea
authors.forename: J K
authors.initials: JK
authors.lastname: Wide
authors.forename: T A
authors.initials: TA
authors.lastname: Paine
authors.forename: M M
authors.initials: MM
authors.lastname: Holmes
authors.forename: B K
authors.initials: BK
authors.lastname: Ormerod
authors.forename: S B
authors.initials: SB
authors.lastname: Floresco
mesh_terms: D000679:Amygdala / Q000187:drug effects; D000818:Animals; D001245:Association Learning / Q000187:drug effects*; D001931:Brain Mapping; D002755:Choice Behavior / Q000187:drug effects*; D003216:Conditioning, Operant / Q000187:drug effects*; D003342:Corpus Striatum / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology*; D005260:Female; D006624:Hippocampus / Q000187:drug effects; D018782:Maze Learning / Q000187:drug effects*; D011939:Mental Recall / Q000187:drug effects*; D009473:Neuronal Plasticity / Q000187:drug effects; D017397:Prefrontal Cortex / Q000187:drug effects; D051381:Rats; D020318:Rats, Long-Evans; D012153:Retention, Psychology / Q000187:drug effects*
chemical_list: C074283:estradiol 3-benzoate; D004958:Estradiol