To the issue of neuro-immuno-endocrine system theory

The review presents the history of evolving views about interrelations between the immune, nervous, and endocrine systems, A number of arguments justify the concept suggesting that they are components of a single regulatory system, since their structures are tightly integrated into each other, and they use similar biologically active substances as signaling molecules. At the same time, distinct molecules, depending on the cell of origin, may be classified as neurotransmitters, hormones, or cytokines. Receptors for cytokines were found on peripheral neurons and vagal nerve endings, e.g., IL-4 regulates synaptic transmission. The ability of immune cells to produce hormones and neuropeptides has been recently proven. Catecholamines may originate from the cells of immune system. Hypothalamic neurosecretory cells express IL-1, and astrocytic glial cells may express interferon. They always act together, in functional regulation by complementing or replacing each other, having a common coordination center. E.g., the anterior lobe of pituitary gland, by secreting growth hormone, may affect synthesis and secretion of thymulin by epithelial thymic cells. Thus, the hypothalamic-pituitary-thymic axis is formed. On this basis, neuroimmunoendocrinology, a new scientific discipline, has emerged. The disorder of a distinct subsystem leads to significant changes in its other compartments. There is not a single type of pathology that would not involve all three components of the whole system. The unity of all components of the system is most clearly observed in stress, traumatic shock, and cytokine storm. Cross-usage of drugs for the therapy of diseases affecting either of the three systems is of particular interest. For example, usage of immunotropic drugs has found applications in the treatment of psychiatric disorders. Pharmacological effects on macrophages are currently implemented in the treatment of endocrine disorders. Thus, sufficient evidence has been accumulated to consider the immune, nervous and endocrine systems an integrated system of physiological regulation which is presumably based on transmission and processing of information.