Neuroscience Forefront ReviewNeural processing of itch

- There are histamine-dependent and -independent types of itch.
- Molecular detectors of pruritogens include Mrgprs, PARs, and many others.
- Spinal transmitters include gastrin releasing peptide and natriuretic polypeptide B.
- Pruritogen-sensitive sensory neurons usually also respond to pain-producing stimuli.
- Pruritogen-responsive sensory neurons connect to an itch-specific central pathway.

While considerable effort has been made to investigate the neural mechanisms of pain, much less effort has been devoted to itch, at least until recently. However, itch is now gaining increasing recognition as a widespread and costly medical and socioeconomic issue. This is accompanied by increasing interest in the underlying neural mechanisms of itch, which has become a vibrant and rapidly-advancing field of research. The goal of the present forefront review is to describe the recent progress that has been made in our understanding of itch mechanisms.