PMC

Topical activation of proteinase-activated receptor (PAR) 2 promotes desensitization of mechanical suprathreshold responses of meningeal nociceptors. (a) Suprathreshold responses of Aδ and C-unit meningeal nociceptors following application of vehicle [synthetic interstitial fluid (SIF)] and subsequent ascending doses of the PAR2 agonist. Individual neuronal responses to suprathreshold stimulation of Aδ-units (b) and C-units (c) 15 min following topical application of 500 μg/cc SLIGRL-NH2. The effect of chronic mast cell (MC) depletion using 48/80 on the duration of PAR2-mediated suprathreshold desensitization of Aδ (d) and C-units (e). *P < 0.05 Student's t-test SLIGRL-NH2 vs. vehicle.

Proteinase-activated receptor (PAR) 2-mediated excitation of meningeal nociceptors. (a) Changes in ongoing discharge rate of Aδ and C-unit meningeal nociceptors following application of vehicle [synthetic interstitial fluid (SIF)] and subsequent ascending doses of the PAR2 agonist. Individual changes in neuronal ongoing discharge rate of Aδ-units (b) and C-units (c) 15 min following topical application of 500 μg/cc SLIGRL-NH2. The effect of chronic mast cell (MC) depletion using 48/80 on the duration of PAR2-mediated activation of Aδ (d) and C-units (e). *P < 0.05 Student's t-test SLIGRL-NH2 vs. vehicle.

Topical activation of proteinase-activated receptor (PAR) 2 promotes increases in mechanical threshold responses of meningeal nociceptors. (a) Threshold responses of Aδ and C-unit meningeal nociceptors following application of vehicle [synthetic interstitial fluid (SIF)] and subsequent ascending doses of the PAR2 agonist SLIGRL-NH2. Individual neuronal responses to threshold mechanical stimulation of Aδ-units (b) and C-units (c) 15 min following topical application of 500 μg/cc SLIGRL-NH2. The effect of chronic mast cell (MC) depletion using 48/80 on the duration of PAR2-mediated threshold sensitization of Aδ (d) and C-units (e). *P < 0.05 Student's t-test SLIGRL-NH2 vs. vehicle.