The psychobiology of posttraumatic stress disorder.

Posttraumatic stress disorder (PTSD) develops after exposure to events that are threatening and/or intensely distressing. Accumulating evidence suggests that intense psychological trauma can cause long-standing alterations in the neurobiological response to stress. These alterations translate into a number of symptoms commonly experienced by patients with PTSD. Current treatments for this disorder are only partially effective in managing the disease, and patients have to endure unpleasant symptoms associated with hyperarousal. As a result, they often withdraw from social interaction and increase the use of central nervous system depressants. Data suggest that biological dysregulation of the glutamatergic, amine neurotransmitter (noradrenergic and serotonergic), and neuroendocrine pathways plays a fundamental part in the pathology of PTSD and may cause brain structural as well as functional abnormalities. Knowledge of these pathologic changes in PTSD provides direction for the development of new treatments that will offer more comprehensive management of PTSD and enable patients to enjoy a much improved quality of life. This article reviews current knowledge regarding the psychobiology of PTSD and considers specific agents that are emerging as key modulators of this pathological process.