Dataset Information

Prediction of individual differences in fear response by novelty seeking, and disruption of contextual fear memory reconsolidation by ketamine.

ABSTRACT: Only a portion of the population exposed to trauma will develop persistent emotional alterations characteristic of posttraumatic stress disorder (PTSD), which illustrates the necessity for identifying vulnerability factors and novel pharmacotherapeutic alternatives. Interestingly, clinical evidence suggests that novelty seeking is a good predictor for vulnerability to the development of excessive and persistent fear. Here, we first tested this hypothesis by analyzing contextual and cued fear responses of rats selected for their high (high responders, HR) or low (low responders, LR) exploration of a novel environment, indicator of novelty seeking. While HR and LR rats exhibited similar sensitivity to the shock and cued fear memory retention, fewer extinction sessions were required in HR than LR animals to reach extinction, indicating faster contextual and cued memory extinction. In a second part, we found an effective disruption of contextual fear reconsolidation by the N-methyl-d-aspartate receptor antagonist ketamine, associated with a down-regulation of early growth response 1 (Egr1) in the hippocampal CA1 area, and up-regulation of brain-derived neurotrophic factor (Bdnf) mRNA levels in the prelimbic and infralimbic cortices. Altogether, these data demonstrate a link between novelty seeking and conditioned fear extinction, and highlight a promising novel role of ketamine in affecting established fear memory.

SUBMITTER: Duclot F

PROVIDER: S-EPMC5017153 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Prediction of individual differences in fear response by novelty seeking, and disruption of contextual fear memory reconsolidation by ketamine.

Duclot Florian F Perez-Taboada Iara I Wright Katherine N KN Kabbaj Mohamed M

Neuropharmacology 20160622

Only a portion of the population exposed to trauma will develop persistent emotional alterations characteristic of posttraumatic stress disorder (PTSD), which illustrates the necessity for identifying vulnerability factors and novel pharmacotherapeutic alternatives. Interestingly, clinical evidence suggests that novelty seeking is a good predictor for vulnerability to the development of excessive and persistent fear. Here, we first tested this hypothesis by analyzing contextual and cued fear res ...[more]

PMID: 27343386

Similar Datasets

Project description:Innate differences in human temperament strongly influence how individuals cope with stress and predispose for specific types of psychopathology. The present study examines the developing brain in an animal model of temperamental differences to understand how altered neurodevelopment may engender differences in emotional reactivity that are stable throughout the animal’s life. We utilize selectively-bred High Responder (bHR) and Low Responder (bLR) rats that exhibit dramatic emotional behavior differences, with bHRs exhibiting exaggerated novelty-exploration, aggression, impulsivity and drug self-administration, and bLRs showing marked behavioral inhibition, exaggerated anxiety- and depressive-like behavior. Using Affymetrix microarrays, we assessed bLR/bHR gene expression in the developing brain on postnatal days (P)7, 14, and 21, focusing on the hippocampus and nucleus accumbens, two regions related to emotionality and known to differ in adult bLR/bHR rats. We found dramatic bLR/bHR gene expression differences in the P7 and P14 hippocampus, with minimal differences in the nucleus accumbens. Some of the most profound differences involved genes critical for neurodevelopment and synaptogenesis. Stereological studies evaluated hippocampal structure in developing bHR/bLR pups, revealing enhanced hippocampal volume and cell proliferation in bLR animals. Finally, behavioral studies showed that the bHR/bLR behavioral phenotypes emerge very early in life, with exploratory differences apparent at P16 and anxiety differences present by P25. Together these data point to specific brain regions and critical periods when the bHR/bLR phenotypes begin to diverge, which may eventually allow us to test possible therapeutic interventions to normalize extreme phenotypes (e.g. the anxiety-prone nature of bLRs or drug addiction proclivity of bHRs). 2x2x3 factorial design with N=6 per group. Factors as follows: 1) Two selectively bred strains of rats (derived from an original Sprague Dawley population) termed High Responders (HR) and Low Responders (LR), 2) Two brain regions, Hippocampus (HPC) and Nucleus Accumbens (N.Acc), 3) Three developmental timepoints, specifically postnatal days 7 (P7), 14 (P14) and 21 (P21).

Dataset Information

Prediction of individual differences in fear response by novelty seeking, and disruption of contextual fear memory reconsolidation by ketamine.

Publications

Prediction of individual differences in fear response by novelty seeking, and disruption of contextual fear memory reconsolidation by ketamine.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets