Peripheral sensitisation of nociceptors via G‐proteindependent potentiation of mechanotransduction currents

摘要: Mechanical stimuli impinging on the skin are converted into electrical signals by mechanically gated ion channels located at peripheral nerve endings of dorsal root ganglion (DRG) neurons. Under inflammatory conditions sensory neurons commonly sensitised to mechanical stimuli; a putative mechanism that may contribute such sensitisation is enhanced responsiveness mechanotransduction channels. Here we show algogens UTP and ATP potentiate mechanosensitive RA currents in peptidergic nociceptive DRG reduce thresholds for induced action potential firing these neurones. Pharmacological characterisation suggests this effect mediated Gq-coupled P2Y2 nucleotide receptor. Moreover, using vitro technique, also increases rates response subpopulation C-fibre nociceptors. Together our findings suggest sensitises cutaneous nociceptors via previously undescribed G-protein-dependent potentiation activated RA-type currents.