Acute episodes of predator exposure in conjunction with chronic social instability as an animal model of post-traumatic stress disorder.
People who are exposed to horrific, life-threatening experiences are at risk for developing post-traumatic stress disorder (PTSD). Some of the symptoms of PTSD include persistent anxiety, exaggerated startle, cognitive impairments and increased sensitivity to yohimbine, an alpha(2)-adrenergic receptor antagonist. We have taken into account the conditions known to induce PTSD, as well as factors responsible for long-term maintenance of the disorder, to develop an animal model of PTSD. Adult male Sprague-Dawley rats were administered a total of 31 days of psychosocial stress, composed of acute and chronic components. The acute component was a 1-h stress session (immobilization during cat exposure), which occurred on Days 1 and 11. The chronic component was that on all 31 days the rats were given unstable housing conditions. We found that psychosocially stressed rats had reduced growth rate, reduced thymus weight, increased adrenal gland weight, increased anxiety, an exaggerated startle response, cognitive impairments, greater cardiovascular and corticosterone reactivity to an acute stressor and heightened responsivity to yohimbine. This work demonstrates the effectiveness of acute inescapable episodes of predator exposure administered in conjunction with daily social instability as an animal model of PTSD.
Department of Psychology, University of South Florida, Tampa, FL 33620, USA.
Phillip R
PR
Zoladz
Cheryl D
CD
Conrad
Monika
M
Fleshner
David M
DM
Diamond
D000818:Animals; D003345:Corticosterone / Q000097:blood; D004195:Disease Models, Animal; D008297:Male; D018782:Maze Learning / Q000502:physiology; D011235:Predatory Behavior; D051381:Rats; D017207:Rats, Sprague-Dawley; D013216:Reflex, Startle / Q000502:physiology; D013313:Stress Disorders, Post-Traumatic / Q000209:etiology*; D013315:Stress, Psychological / Q000150:complications
D003345:Corticosterone