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Substance P activates Mas-related G protein-coupled receptors to induce itch.

ABSTRACT: Substance P (SP) is linked to itch and inflammation through activation of receptors on mast cells and sensory neurons. There is increasing evidence that SP functions through Mas-related G protein-coupled receptors (Mrgprs) in addition to its conventional receptor, neurokinin-1.Because Mrgprs mediate some aspects of inflammation that had been considered mediated by neurokinin-1 receptor (NK-1R), we sought to determine whether itch induced by SP can also be mediated by Mrgprs.Genetic and pharmacologic approaches were used to evaluate the contribution of Mrgprs to SP-induced scratching behavior and activation of cultured dorsal root ganglion neurons from mice.SP-induced scratching behavior and activation of cultured dorsal root ganglion neurons was dependent on Mrgprs rather than NK-1R.We deduce that SP activates MrgprA1 on sensory neurons rather than NK-1R to induce itch.

SUBMITTER: Azimi E

PROVIDER: S-EPMC5546940 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Substance P activates Mas-related G protein-coupled receptors to induce itch.

Azimi Ehsan E Reddy Vemuri B VB Pereira Paula Juliana Seadi PJS Talbot Sebastien S Woolf Clifford J CJ Lerner Ethan A EA

The Journal of allergy and clinical immunology 20170220 2

<h4>Background</h4>Substance P (SP) is linked to itch and inflammation through activation of receptors on mast cells and sensory neurons. There is increasing evidence that SP functions through Mas-related G protein-coupled receptors (Mrgprs) in addition to its conventional receptor, neurokinin-1.<h4>Objective</h4>Because Mrgprs mediate some aspects of inflammation that had been considered mediated by neurokinin-1 receptor (NK-1R), we sought to determine whether itch induced by SP can also be med ...[more]

PMID: 28219706

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Substance P activates Mas-related G protein-coupled receptors to induce itch.

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Substance P activates Mas-related G protein-coupled receptors to induce itch.

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