Adolescent fluoxetine history impairs spatial memory in adult male, but not female, C57BL/6 mice.
J Affect Disord 2019;
249:347-356. [PMID:
30807936 PMCID:
PMC6951803 DOI:
10.1016/j.jad.2019.02.051]
[Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/13/2019] [Accepted: 02/17/2019] [Indexed: 11/21/2022]
Abstract
BACKGROUND
Epidemiological reports indicate that mood-related disorders are common in the adolescent population. The prevalence of juvenile major depressive disorder has resulted in a parallel increase in the prescription rates of fluoxetine (FLX) within this age group. Although such treatment can last for years, little is known about the enduring consequences of adolescent antidepressant exposure on memory-related performance.
METHODS
We exposed separate groups of adolescent (postnatal day [PD] 35) male and female C57BL/6 mice to FLX (20 mg/kg) for 15 consecutive days (PD35-49). Three weeks after FLX exposure (PD70), we assessed learning and memory performance on a single-day training object novelty recognition test, or a spatial memory task on the Morris water maze (MWM).
RESULTS
We found that FLX pretreatment did not influence performance on either the object novelty recognition task or the MWM, 24 h after training. Conversely, 48 h post spatial-training on the MWM, FLX pretreated male mice spent significantly less time on the quadrant of the missing platform during a standard probe trial. No differences in MWM performance were observed in the adult female mice pretreated with FLX.
LIMITATIONS
A limitation of this study is that normal adolescent mice (i.e., non-stressed) were evaluated for memory-related behavior three weeks after antidepressant exposure. Thus, it is possible that FLX pre-exposure in combination with animal models for the study of depression may yield different results.
CONCLUSION
Together, these results demonstrate enduring spatial memory-related deficiencies after pre-exposure to FLX during adolescence in male, but not female, C57BL/6 mice.
Collapse