[The concept of stress and the role of hypothalamic and extra-hypothalamic corticotropin-releasing factor (CRF) in the integration of the neuroendocrine and immune responses. Clinical and experimental aspects].

Several evidences suggest the existence of a bidirectional link between the immune and neuroendocrine systems. This relationship explains how a "non cognitive" stimulus (as antigen) can activate the neuroendocrine axis through the inflammatory substances (cytokines) in the same manner as a stress response. A disregulation of this response can determine the basis for a pathological situation. The key-peptide of the stress response is hypothalamic CRF, though also extra-hypothalamic sources, such as the cells of the immune system, are present and could play an important role in the peripheral regulation of stress response.