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Gate control of mechanical itch by a subpopulation of spinal cord interneurons.

ABSTRACT: Light mechanical stimulation of hairy skin can induce a form of itch known as mechanical itch. This itch sensation is normally suppressed by inputs from mechanoreceptors; however, in many forms of chronic itch, including alloknesis, this gating mechanism is lost. Here we demonstrate that a population of spinal inhibitory interneurons that are defined by the expression of neuropeptide Y::Cre (NPY::Cre) act to gate mechanical itch. Mice in which dorsal NPY::Cre-derived neurons are selectively ablated or silenced develop mechanical itch without an increase in sensitivity to chemical itch or pain. This chronic itch state is histamine-independent and is transmitted independently of neurons that express the gastrin-releasing peptide receptor. Thus, our studies reveal a dedicated spinal cord inhibitory pathway that gates the transmission of mechanical itch.

SUBMITTER: Bourane S

PROVIDER: S-EPMC4700934 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Gate control of mechanical itch by a subpopulation of spinal cord interneurons.

Bourane Steeve S Duan Bo B Koch Stephanie C SC Dalet Antoine A Britz Olivier O Garcia-Campmany Lidia L Kim Euiseok E Cheng Longzhen L Ghosh Anirvan A Ma Qiufu Q Goulding Martyn M

Science (New York, N.Y.) 20151001 6260

Light mechanical stimulation of hairy skin can induce a form of itch known as mechanical itch. This itch sensation is normally suppressed by inputs from mechanoreceptors; however, in many forms of chronic itch, including alloknesis, this gating mechanism is lost. Here we demonstrate that a population of spinal inhibitory interneurons that are defined by the expression of neuropeptide Y::Cre (NPY::Cre) act to gate mechanical itch. Mice in which dorsal NPY::Cre-derived neurons are selectively abla ...[more]

PMID: 26516282

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