Substance P/NK1 Receptor Phosphorylation Assays

Tachykinin 1 (NK1) receptor is a member of the tachykinin receptor family, which is characterized by the ability to bind tachykinin neuropeptides resulting in spasmodic contractions. Substance P (SP) is the most selective agonist towards NK1. The NK1 receptor is a 7TM receptor that associates with the G-protein q11. NK1 is widely distributed in both the central nervous system and peripheral tissues including the substantia nigra, the hypothalamus, the lateral habenula, the inferior colliculus the central amygdala, the frontal cortex and the sensorimotor cortex as well as the gastrointestinal tract. Antagonists such as aprepitant and fosaprepitant were approved for the prevention of nausea and vomiting associated with cancer chemotherapy. NK1 receptor desensitization, β-arrestin recruitment and internalization are regulated by phosphorylation of carboxyl-terminal threonine344/serine347 (pT344/pS347-NK1).This nomenclature refers to the human NK1 receptor. This phosphorylation motif is highly conserved across species but corresponds to pT344/pS346/pS347-NK1 in mice and rats. For more information on NK1 pharmacology please refer to the IUPHAR database. For further reading refer to:
Barrett J, Canning B, Coulson J, Dombrowsky E, Douglas SD, Fong TM, Heyward CY, Leeman SE, Remeshwar P. Tachykinin receptors (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database. IUPHAR/BPS Guide to Pharmacology CITE. 2019; 2019(4).