Chronic adolescent stress increases exploratory behavior but does not appear to change the acute stress response in adult male C57BL/6 mice

• DOI: 10.1016/j.ynstr.2021.100388
• Publication Date: 2021-09-04T14:58:13Z
• Authors: Oliver Sturman; Lukas von Ziegler; Mattia Privitera; Rebecca Waag; Sian Duss; Yannick Vermeiren; Letizia Giovagnoli; Peter de Deyn; Johannes Bohacek
• Keywords: Neurophysiology and neuropsychology; 0301 basic medicine; Neurosciences. Biological psychiatry. Neuropsychiatry; Anxiety; Hippocampus; Mice; 03 medical and health sciences; 0302 clinical medicine; ANIMAL-MODEL; ANXIETY; Original Research Article; BRAIN; RC346-429; Acute stress; Biology; GENE-EXPRESSION; SOCIAL INSTABILITY STRESS; Social stress; QP351-495; APICAL DENDRITES; Adolescence; 3. Good health; DEFEAT; EARLY-LIFE STRESS; NOREPINEPHRINE; LOCUS-COERULEUS; Noradrenaline; Human medicine; Neurology. Diseases of the nervous system; Transcriptome; RC321-571

Neurobiology of Stress, 15<br/>ISSN:2352-2895<br/>Chronic stress exposure in adolescence can lead to a lasting change in stress responsiveness later in life and is associated with increased mental health issues in adulthood. Here we investigate whether the Chronic Social Instability (CSI) paradigm influences the behavioral and molecular responses to novel acute stressors in mice, and whether it alters physiological responses influenced by the noradrenergic system. Using large cohorts of mice, we show that CSI mice display a persistent increase in exploratory behaviors in the open field test alongside small but widespread transcriptional changes in the ventral hippocampus. However, both the transcriptomic and behavioral responses to novel acute stressors are indistinguishable between groups. In addition, the pupillo-metric response to a tail shock, known to be mediated by the noradrenergic system, remains unaltered in CSI mice. Ultra-high performance liquid chromatography analysis of monoaminergic neurotransmitter levels in the ventral hippocampus also shows no differences between control or CSI mice at baseline or in response to acute stress. We conclude that CSI exposure during adolescence leads to persistent changes in exploratory behavior and gene expression in the hippocampus, but it does not alter the response to acute stress in adulthood and is unlikely to alter the function of the noradrenergic system.<br/>