The role of estrogen receptor manipulation on persistent fear memory induced by traumatic stress exposure
Date
2022
Authors
Journal Title
Journal ISSN
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Publisher
University of Delaware
Abstract
Post traumatic stress disorder (PTSD) is a debilitating psychiatric disorder
which stems from fear memory persistence after exposure to a traumatic experience.
PTSD is associated with a high socioeconomic cost, as well as a higher prevalence rate
in women than in men, though the reason behind this sex difference remains unknown.
A possible explanation may be cyclic changes in vascular estrogen release, which may
be a contributing factor to the higher prevalence of PTSD, though the role of estrogen
receptors in modulating traumatic stress effects has been insufficiently explored. By
using a well-validated PTSD model (single prolonged stress – SPS) in female rats, we
first studied the effects of antagonizing nuclear estrogen receptors (Experiment 1),
finding that SPS induced persistent fear memory (measured using freezing) and that
this response was not affected by antagonism of nuclear estrogen receptors. Following
this, we examined the effects of agonizing G-protein coupled estrogen receptors
(GPERs, Experiment 2), finding that SPS had no effect on persistent fear memory, and
that activation of GPERs prior to SPS had no effect on persistent fear memory.
Finally, we studied the effects of activating estrogen receptors utilizing 17β-estradiol,
and found that SPS increased persistent fear memory (measured using darting), and
that this enhancement in persistent fear memory was attenuated by activation of
estrogen receptors prior to SPS. Overall, the results of the study suggest that SPS
effects on persistent fear memory can be observed in female rats (by measuring
multiple behaviors) and that increasing estrogen levels prior to SPS attenuates
persistent fear memory induced by SPS in female rats.
Description
Keywords
Fear memory, Estrogen receptors, Traumatic stress