A. CFA reduced withdrawal latency within 24 hrs post-CFA. AMG9810 (30 mg/kg, i.p.) reversed CFA-induced thermal hyperalgesia within 15 min, with paw-flick latencies returning to pre-drug levels 60 min post administration. AMG9810 also elevated paw-flick latencies of control (saline treated) rats with 15 min of administration. *p < 0.05 vs. post-CFA, #p < 0.05 vs. pre-CFA, n = 5-6. B. Systemic administration of the selective TRPV1 receptor antagonist, AMG9810 (30 mg/kg i.p.) failed to alter CFA-induced guarding behavior 24 hours following injury, p > 0.05 vs. vehicle. C. Pre-conditioning values did not differ between treatment groups, therefore values were pooled for graphical representation. Lidocaine increased time spent in the lidocaine paired chambers in both the AMG9810 and vehicle treated rats, *p < 0.05 vs. pre-conditioning, n = 5. D. Difference scores calculated as test time - preconditioning time spent in the lidocaine chamber confirm that CFA treated rats increased time spent in the lidocaine paired chambers in both the vehicle and AMG9810 treatment groups, *p < 0.05 vs. saline/vehicle.
Okun et al. Molecular Pain 2011 7:4 doi:10.1186/1744-8069-7-4