BIOLOGICAL EFFECTS OF SUBSTANCE P IN THE BRAIN

Substance P (SP) is a non-cholinergic neuropeptide produced at different levels in different cell types, including mast cells (MCs) and neurons. SP is involved in the regulation of many central nervous system (CNS) disorders such as anxiety, stress, mood disorders, and neurogenesis, and functions such as synapse growth, dendritic formation, respiration, neurotoxicity, nociception and pain. This neuropeptide produces inflammation after binding to its natural killer (NK) cell receptor. MCs and neurons possess the NK1 receptor and are activated by SP to produce inflammatory molecules such as cytokines and chemokines. In this article, we report that SP not only induces the generation of pro-inflammatory proteins, but also acts synergistically with cytokines such as IL-33 to enhance the inflammatory process.