Figure 3.

Hypothalamic-pituitary-adrenal (HPA) axis and hippocampal negative feedback regulation. The HPA axis is activated by stress and integrates stress responses. Anxiety responses via activation of the amygdala can exacerbate the stress response through its projections to the paraventricular nucleus of the hypothalamus (PVN). The hippocampus (HPC) is important for the evaluation of stress and is a site of glucocorticoid receptor (GR)- and mineralocorticoid (MR)-mediated negative feedback to the PVN. Release of the neuropeptides corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) from the hypothalamus promotes the release of adrenocorticotropin (ACTH) from the pituitary. ACTH then stimulates the release of glucocorticoids from the adrenal cortices. These hormones circulate to the body and brain and bind to intracellular steroid hormone receptors. (CRF) Corticotropin-releasing factor, (MR) mineralocorticoid receptor.