In a new study, Chen’s lab has identified NMBR as a novel itch receptor for mediating histaminergic itch in the spinal cord.  Using a combination of pharmacological, behavioral and genetic approaches, the study delineates the respective roles for GRPR and NMBR in itch transmission.   The study reveals that NMB, an endogenous ligand for NMBR, exclusively activates NMBR, and additionally acts as a functional antagonist for GRPR.   In contrast, GRP, a cognate ligand for GRPR, activates both GRPR and NMBR in response to both histamine and chloroquine, a histamine-independent pruritogen.  GRP-GRPR signaling has a unique role in mediating chloroquine-induced itch.  The new study also for the first time places NMBR interneurons upstream of GRPR neurons in the dorsal spinal cord.  For more details, please see:

 Zhou-Feng Chen  Chen Lab