Synaptic control of spinal GRPR + neurons by local and long-range inhibitory inputs

Significance Itch signal processing is dynamically modulated. However, the neural mechanism underlying the modulation of itch processing at the spinal level remains elusive. Here, we studied the inhibitory control of spinal itch circuitry. We demonstrated that, in addition to local inhibitory neurons, long-range inhibitory neurons also play a critical role in modulating the spinal itch circuit by forming inhibitory synapses with spinal GRPR + neurons, which are known to be essential for itch processing in the spinal cord. Our study revealed the mechanism underlying the inhibitory control of the spinal itch circuit.