Differential effects of acute progesterone administration on spatial and object memory in middle-aged and aged female C57BL/6 mice. Horm Behav 2008 Aug;54(3):455-62
Date
07/01/2008Pubmed ID
18585714Pubmed Central ID
PMC2586174DOI
10.1016/j.yhbeh.2008.05.010Scopus ID
2-s2.0-47549108627 (requires institutional sign-in at Scopus site) 38 CitationsAbstract
The present study examined the effects of acute progesterone administration on hippocampal-dependent memory consolidation in ovariectomized middle-aged (16 months old) and aged (22 months old) female mice. Spatial memory was tested in a 2-day Morris water-maze task and object memory was tested using an object recognition task with 24- and 48-h delays. Immediately after water-maze training, mice received i.p. injections of vehicle, or 5.0, 10.0, or 20.0 mg/kg of water-soluble progesterone. Twenty-four hours later, retention of the platform location was tested. No overnight forgetting of the platform location was observed in middle-aged vehicle-treated mice. Acute progesterone administration had no effect on spatial memory in middle-aged mice. However, aged vehicle-treated mice demonstrated impaired memory for the platform location on Day 2 relative to Day 1. Twenty mg/kg, but not 5 or 10 mg/kg, progesterone reversed these deficits, suggesting that 20 mg/kg progesterone can improve spatial memory in aged females. In the object recognition task, mice explored two identical objects and then immediately received vehicle or progesterone injections. In middle-aged mice, 10 and 20 mg/kg progesterone enhanced object memory consolidation, relative to chance, after 24-h, but all doses were ineffective after 48-h. In aged mice, 10 mg/kg progesterone enhanced object memory consolidation, relative to chance, after 24 h, whereas both 5 and 10 mg/kg progesterone enhanced memory after 48 h. Together, these results indicate that acute progesterone differentially enhances hippocampal-dependent memory in middle-aged and aged females.
Author List
Lewis MC, Orr PT, Frick KMAuthor
Karyn Frick BA,MA,PhD Professor in the Psychology department at University of Wisconsin - MilwaukeeMESH terms used to index this publication - Major topics in bold
AgingAnimals
Dose-Response Relationship, Drug
Exploratory Behavior
Female
Hippocampus
Maze Learning
Mental Recall
Mice
Mice, Inbred C57BL
Orientation
Pattern Recognition, Visual
Progesterone