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Relief of itch by scratching: state-dependent inhibition of primate spinothalamic tract neurons.

ABSTRACT: Itch is relieved by scratching, but the neural mechanisms that are responsible for this are unknown. Spinothalamic tract (STT) neurons respond to itch-producing agents and transmit pruritic information to the brain. We observed that scratching the cutaneous receptive field of primate STT neurons produced inhibition during histamine-evoked activity but not during spontaneous activity or activity evoked by a painful stimulus, suggesting that scratching inhibits the transmission of itch in the spinal cord in a state-dependent manner.

SUBMITTER: Davidson S

PROVIDER: S-EPMC3006451 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature

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Relief of itch by scratching: state-dependent inhibition of primate spinothalamic tract neurons.

Davidson Steve S Zhang Xijing X Khasabov Sergey G SG Simone Donald A DA Giesler Glenn J GJ

Nature neuroscience 20090406 5

Itch is relieved by scratching, but the neural mechanisms that are responsible for this are unknown. Spinothalamic tract (STT) neurons respond to itch-producing agents and transmit pruritic information to the brain. We observed that scratching the cutaneous receptive field of primate STT neurons produced inhibition during histamine-evoked activity but not during spontaneous activity or activity evoked by a painful stimulus, suggesting that scratching inhibits the transmission of itch in the spin ...[more]

PMID: 19349977

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