Figure 3
From: Transient inflammation-induced ongoing pain is driven by TRPV1 sensitive afferents
A. RTX (0.1 mg/kg, i.p.) treatment 4 days prior to testing blocked thermal nociception with all responses on the hot plate (52°C) reaching the cut-off time (32 s). CFA reduced the thermal response latency within 24 hr in animals that received vehicle for RTX. Thermal hypersensitivity was completely blocked in the RTX treated group. *p < 0.05 vs. pre-RTX; #p < 0.05 vs. vehicle, n = 7. B. RTX treatment 4 days prior to testing blocked CFA induced guarding of the hindpaw observed 24 hours following injury. *p < 0.05 vs. vehicle treated, n = 8-10. C. RTX treatment 1 day prior to testing prior to habituation blocked CPP to chambers paired with lidocaine administration into the popliteal fossa in CFA treated rats 24 hr post-CFA. Rats that received saline into the hindpaw failed to show preference for the lidocaine paired chamber irrespective of RTX treatment. *p < 0.05 vs. pre-conditioning, n = 6-8. D. Difference scores calculated as test time - preconditioning time spent in lidocaine chamber confirm that only CFA treated rats that did not receive RTX (Vehicle) showed preference for the lidocaine paired chamber. *p < 0.05 vs. saline treated group.