Figure 4.

Effect of PAR₂ activation on joint fibre firing in response to a mechanical stimulus. Example of a single unit recording from a single joint fibre before and 3 min after (A) 100 nmol scrambled control peptide 2-furoyl-OLGRIL-NH₂ and (B) 100 nmol 2-furoyl-LIGRLO-NH₂ during normal and noxious rotation of the knee joint. Time course of close intra-arterial injection of either 2-furoyl-LIGRLO-NH₂ (at doses 1–100 nmol·100 μL⁻¹) or scrambled peptide, 2-furoyl-OLGRIL-NH₂ (100 nmol·100 μL⁻¹) on knee joint afferent activity over 15 min in response to (C) normal and (D) noxious rotation of the knee joint. Baseline values before drug administration were used as control. Data are shown as mean ± SEM, n = 10–21. Two-way anova followed by Bonferroni test. *P < 0.05 compared with scrambled peptide.