R-Flurbiprofen Reduces Neuropathic Pain in Rodents by Restoring Endogenous Cannabinoids
Figure 2
Time course of the nociceptive behavior in nerve-injured and naïve rats treated with R-flurbiprofen or vehicle (n = 6 per group) and glutamate release in the dorsal horn of the spinal cord.
a In SNI, the daily drug treatment started the day after nerve injury. Mechanical hyperalgesia was assessed by recording the paw withdrawal threshold to stimulation with a Dynamic Plantar Aesthesiometer, b cold allodynia as paw withdrawal latency after exposure to a 10°C cold plate. Comparison of the areas under the effect x time curves revealed statistically significant differences between R-flurbiprofen and vehicle treatment (P<0.05). c In naïve rats mechanical sensitivity was assessed with a Dynamic Plantar Aesthesiometer, and d heat sensitivity as withdrawal latency to noxious heat stimulation in the Hargreaves test. R-flurbiprofen was injected at time zero, it had no effect. e Time course of glutamate release in the dorsal horn of the lumbar spinal cord in rats treated with 9 mg/kg R-flurbiprofen i.p. or vehicle 30 min before application of capsaicin cream (0.1%) onto the exposed sciatic nerve (time “zero”). Glutamate was analyzed in microdialysates from the dorsal horn in a colorimetric enzyme assay. The peak glutamate release after capsaicin application differed significantly between the treatment groups (n = 6; P<0.05).