Itch is described as an irritating sensation that triggers a desire to scratch. However, this definition hardly seems fitting for the millions of people who suffer from intractable itch. Indeed, the Buddhist philosopher Nā´áäāgārjuna more aptly stated, “There is pleasure when an itch is scratched. But to be without an itch is more pleasurable still.” Chronic itch is widespread and very difficult to treat. In this review we focus on the molecules, cells and circuits in the peripheral and central nervous systems that drive acute and chronic itch transmission. Understanding the itch circuitry is critical to developing new therapies for this intractable disease.
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We are grateful to M. Pellegrino for critical comments on the manuscript. This work was supported by US National Institutes of Health (NIH) grants AR059385 and DOD007123A (D.M.B.), the intramural research program of the NIH NIDCR (M.A.H.) and a US National Science Foundation Fellowship (S.R.W.).
All authors are in the process of filing a patent application related to some of the results described in this manuscript.
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Bautista, D., Wilson, S. & Hoon, M. Why we scratch an itch: the molecules, cells and circuits of itch. Nat Neurosci 17, 175–182 (2014). https://doi.org/10.1038/nn.3619
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