Early life adversity decreases pre-adolescent fear expression by accelerating amygdala PV cell development
Abstract
Early life adversity (ELA) is associated with increased risk for stress-related disorders later in life. The link between ELA and risk for psychopathology is well established but the developmental mechanisms remain unclear. Using a mouse model of resource insecurity, limited bedding (LB), we tested the effects of LB on the development of fear learning and neuronal structures involved in emotional regulation, the medial prefrontal cortex (mPFC) and basolateral amygdala (BLA). LB delayed the ability of peri-weanling (21 days old) mice to express, but not form, an auditory conditioned fear memory. LB accelerated the developmental emergence of parvalbumin (PV) positive cells in the BLA and increased anatomical connections between PL and BLA. Fear expression in LB mice was rescued through optogenetic inactivation of PV positive cells in the BLA. The current results provide a model of transiently blunted emotional reactivity in early development, with latent fear-associated memories emerging later in adolescence.
Data availability
Data has been deposited in the Brown Digital Repository with the following DOI: https://doi.org/10.26300/9krc-h052
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Data from Early life adversity decreases pre-adolescent fear expression by accelerating amygdala PV cell developmentBrown Digital Repository, doi:10.26300/9krc-h052.
Article and author information
Author details
Funding
National Institutes of Health (MH115914)
- Kevin G Bath
National Institutes of Health (MH115049)
- Kevin G Bath
National Institutes of Health (NS105219)
- Gabriela Manzano Nieves
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#19-10-0003) of Brown University.
Copyright
© 2020, Manzano Nieves et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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