Figure 1.
Schematic of nociceptor neurons and their functions. Nociceptor cell bodies reside in dorsal root ganglia (DRG) and trigeminal ganglia (TG). Nociceptor neurons have two axons: peripheral axons terminate in the skin, muscle, and gut and central axons terminate in the spinal cord and trigeminal nucleus dorsal horn. A subset of nociceptor neurons can also sense itch as pruriceptors. TRPV1 and TRPA1 ion channels are critical for the transduction and transmission of both pain and itch.