Related Experiment Video
Updated: Aug 14, 2026

The Unpredictable Chronic Mild Stress Protocol for Inducing Anhedonia in Mice
Published on: October 24, 2018
Alterations in cortisol negative feedback inhibition as examined using the ACTH response to cortisol administration
Rachel Yehuda1, Ren-Kui Yang, Monte S Buchsbaum
1The Traumatic Stress Studies Program, Psychiatry Department, Mount Sinai School of Medicine, and the Bronx Veterans Affairs Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA. rachel.yehuda@med.va.gov
Objective:
Studies using the dexamethasone suppression test (DST) have demonstrated an enhanced negative feedback inhibition at the pituitary in PTSD, but have not provided information about central feedback effects, since dexamethasone (DEX) does not penetrate the brain well. The authors therefore examined the change in ACTH and cortisol before and after cortisol administration, which acts at central feedback sites in addition to peripheral targets.
Method:
Blood was obtained from 31 male veterans (18 with PTSD) before, and 8, 40 and 95 min following injection of 17.5 mg cortisol and placebo.
Results:
A greater decline in ACTH was observed after cortisol injection in PTSD.
Conclusions:
Central as well as peripheral negative feedback inhibition may be altered in PTSD.
Related Concept Videos
Cushing Syndrome II: Pathophysiology
Cushing Syndrome I: Introduction
Post-traumatic Stress Disorder
Symptoms and Behavioral Manifestations
A spectrum of distressing symptoms characterizes PTSD. Recurrent flashbacks, where individuals involuntarily relive traumatic events, are a...
Introduction to Stress and Lifestyle

