Psychoneuroendocrinology of posttraumatic

stress disorder Psiconeuroendocrinologia do transtorno de estresse pós-traumático Abst rac t Objective: To review the literature on neurobiological findings related to hypothalamic-pituitary-adrenal axis dysfunctions associated with posttraumatic stress disorder. Method: The relevant scientific findings were described according to the date of publication and the characteristics of the studies: preclinical studies, studies on early life violence as a risk factor, and clinical findings related to patients diagnosed with posttraumatic stress disorder. Results: A rich literature on hypothalamic-pituitary-adrenal axis dysfunctions and posttraumatic stress disorder was found. Neurobiological findings showed that posttraumatic stress disorder is associated with hypothalamic-pituitary-adrenal axis dysfunctions and other brain-related structures: prefrontal cortex, hippocampus, and amygdala. Posttraumatic stress disorder patients have low plasma levels of cortisol and present increased responsivity of glucocorticoid receptors, suggesting that the inhibition of negative feedback plays a significant role in the disorder pathology. Preclinical studies using animal models of maternal deprivation showed that depending on the moment the trauma occurred during the development, different hypothalamic-pituitary-adrenal axis dysfunctions were produced. Clinical studies showed that early life stress is related to the development of psychopathologies during adulthood. Conclusions: There is robust evidence of hypothalamic-pituitary-adrenal axis dysfunctions related to posttraumatic stress disorder, and the mechanisms underlying this association are being better understood