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Peripheral Mechanisms of Itch

  • Changxiong J. Guo
    Affiliations
    Center for the Study of Itch & Sensory Disorders, Department of Anesthesiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
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  • Nathaniel S. Grabinski
    Affiliations
    Center for the Study of Itch & Sensory Disorders, Department of Anesthesiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
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  • Qin Liu
    Correspondence
    Correspondence: Qin Liu, Center for the Study of Itch & Sensory Disorders, Department of Anesthesiology, School of Medicine, Washington University in St. Louis, 660 South Euclid Avenue, CB8054, St. Louis, Missouri 63110, USA.
    Affiliations
    Center for the Study of Itch & Sensory Disorders, Department of Anesthesiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
    Search for articles by this author
Published:November 24, 2021DOI:https://doi.org/10.1016/j.jid.2021.10.024
      Itch is a universally experienced sensation, and chronic itch can be as diabolically debilitating as pain. Recent advances have not only identified the neuronal itch sensing circuitry, but also have uncovered the intricate interactions between skin and immune cells that work together with neurons to identify itch-inducing irritants. In this review, we will summarize the fundamental mechanisms of acute itch detection in the skin, as well as highlight the recent discoveries relating to this topic.

      Abbreviations:

      5-HT (5-hydroxytryptamine), ACD (allergic contact dermatitis), AD (atopic dermatitis), AEW (acetone:ether water), CGRP (calcitonin gene-related peptide), CTCL (cutaneous T-cell lymphoma), DRG (dorsal root ganglia), GRP (gastrin-releasing peptide), HTR (serotonin receptor), KC (keratinocyte), KOR (κ-opioid receptor), LTC4 (cysteinyl leukotriene), LTMR (low-threshold mechanoreceptor), miR (microRNA), NP (nonpeptidergic), NPPB (brain natriuretic peptide), PAR (protease-activated receptor), SP (substance P), Th (T helper), TG (trigeminal ganglia), TLR (toll-like receptor)
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