FIGURE 2.

Interactions and regulation of nervous and immune systems. This diagram represents the close interaction between the nervous and immune system. The nervous system has many afferences from the immune system: by immune system transmitters: cytokines, peptides, and others, including immune cells (fine lines); the immune cells and their transmitters acceded to nervous system trespassing the blood‐brain barrier by circumventricular organs, capillary diapedesis, and cerebrospinal fluid inter‐neuronal‐glial space; and by nervous impulses via sensory neurons (spinothalamic tract) and peripheral nervous system, autonomous nervous system included (fine open arrow at left bottom). The main effectors of the nervous system to immune system are hypothalamic hormones (mainly by the hypothalamic‐pituitary adrenal axis), and peripheral nervous system (PNS), but also neurotransmitters (descending open bold arrows). Scheme designed with data mainly from references [22] and [25]. Other more complex explanations [28] are not represented