BioProject

Itch is an unpleasant skin sensation which can be triggered by exposure to many chemicals including those released by mast cells. More...

Itch is an unpleasant skin sensation which can be triggered by exposure to many chemicals including those released by mast cells. The Nppb-expressing class of sensory neurons when activated elicit scratching responses in mice, however, it is unclear which itch-inducing agents stimulate these cells and the receptors involved. Here, we identify receptors expressed by Nppb-neurons and demonstrate the functional importance of these receptors as sensors of endogenous pruritogens released by mast cells. Our search for receptors in Nppb-neurons revealed that they express leukotriene, serotonin, and sphingosine-1-phosphate receptors. Targeted cell ablation, calcium imaging of primary sensory neurons, and conditional receptor knockout studies demonstrate that these receptors induce itch by the direct stimulation of Nppb-neurons and neurotransmission through the canonical GRP-dependent spinal cord itch pathway. Together our results define a molecular and cellular pathway for mast cell-induced itch. Overall design: Examination of transcriptome (RNA-seq) of 2 different populations of DRG neurons in quadruplicates. Less...