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Ghrelin is a persistent biomarker for chronic stress exposure in adolescent rats and humans.

ABSTRACT: Prolonged stressor exposure in adolescence enhances the risk of developing stress-sensitive mental illnesses, including posttraumatic stress disorder (PTSD), for many years following exposure cessation, but the biological underpinnings of this long-term vulnerability are unknown. We show that severe stressor exposure increased circulating levels of the hormone acyl-ghrelin in adolescent rats for at least 130 days and in adolescent humans for at least 4.5 years. Using a rodent model of longitudinal PTSD vulnerability in which rodents with a history of stressor exposure during adolescence display enhanced fear in response to fear conditioning administered weeks after stressor exposure ends, we show that systemic delivery of a ghrelin receptor antagonist for 4 weeks surrounding stressor exposure (2 weeks during and 2 weeks following) prevented stress-enhanced fear memory. These data suggest that protracted exposure to elevated acyl-ghrelin levels mediates a persistent vulnerability to stress-enhanced fear after stressor exposure ends.

SUBMITTER: Yousufzai MIUA

PROVIDER: S-EPMC5895712 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Ghrelin is a persistent biomarker for chronic stress exposure in adolescent rats and humans.

Yousufzai Muhammad I Ul Akbar MIUA Harmatz Elia S ES Shah Mohsin M Malik Muhammad O MO Goosens Ki A KA

Translational psychiatry 20180411 1

Prolonged stressor exposure in adolescence enhances the risk of developing stress-sensitive mental illnesses, including posttraumatic stress disorder (PTSD), for many years following exposure cessation, but the biological underpinnings of this long-term vulnerability are unknown. We show that severe stressor exposure increased circulating levels of the hormone acyl-ghrelin in adolescent rats for at least 130 days and in adolescent humans for at least 4.5 years. Using a rodent model of longitudin ...[more]

PMID: 29643360

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Ghrelin is a persistent biomarker for chronic stress exposure in adolescent rats and humans.

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Ghrelin is a persistent biomarker for chronic stress exposure in adolescent rats and humans.

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