The modality-specific contribution of peptidergic and non-peptidergic nociceptors is manifest at the level of dorsal horn nociresponsive neurons.

摘要: We previously demonstrated that genetic and/or pharmacological ablation of the TRPV1+/peptidergic or MrgprD+/non-peptidergic subset nociceptors produced selective, modality-specific deficits in behavioural responses to heat and mechanical stimuli, respectively. To assess whether this contribution is also manifest at level spinal cord neuron responsiveness, here we made extracellular recordings from lumbar dorsal horn neurons mouse response graded thermal stimulation. found that, following intrathecal injection capsaicin eliminate central terminals TRPV1+ nociceptors, region laminae I V lost responsiveness noxious (whether generated by a contact probe diode laser), with no change their In contrast, MrgprD+ afferents did not alter heat, but reduced firing superficial nociceptive-specific stimulation decreased relative number wide dynamic range were exclusively mechanosensitive. Neither procedure responded cold. These findings support conclusion are necessary probably sufficient for activation despite polymodal properties, provide contributions properties neurons.