[Serotonin and its immune and physiological effects]

Now that the neurotransmitter serotonin modulates the immune system cells, and its main sources for antigenpresenting cells and lymphocytes are enterochromaffin cells of the gut, peripheral nerves, platelets and mast cells in case of inflammation. Immune cells uptake serotonin because they express receptors for this monoamine and intracellular serotonin transporters. The dendritic cells have a mechanism to transfer serotonin to T lymphocytes during antigen presentation. The macrophages and T cells have the ability to serotonin synthesis. Serotonin can influence mobility and proliferation of lymphocytes, phagocytosis, cytolytic properties, synthesis of chemokines and cytokines. Diversity of immunomodulating effects of serotonin is determined by heterogeneity of serotoninergic receptors. Immunomodulating action of serotonin is evidence of the close relationship between nervous and immune systems.