Fig. 5.
Capsazepine mitigates hyperalgesia and spontaneous pain in ethanol-withdrawn (EtOH-WD) rats. (A) The paw withdrawal latency (PWL) to thermal stimuli was significantly reduced in EtOH-WD rats at 24-h withdrawal, in comparison with the Naïve counterparts. $$$P < 0.001 relative to respective baseline. Two-way repeated measures ANOVA followed by Tukey post hoc comparison. (B) Intra-lateral habenula injection of capsazepine (CPZ) significantly increased the nociceptive response in EtOH-WD rats. The change in nociceptive response is expressed as percent maximum peak effect (%MPE). Intra–lateral habenula DNQX significantly increased PWL in both Naïve and EtOH-WD rats. (C) In the place conditioning paradigm, intra–lateral habenula CPZ significantly increased the place conditioning score in EtOH-WD rats; intra–lateral habenula 6, 7-Dinitroquinoxaline-2, 3-dione (DNQX) significantly increased the conditioned place paradigm score in both Naïve and EtOH-WD rats. **P < 0.01, ***P < 0.001 relative to respective artificial cerebrospinal fluid treatment; ###P < 0.001 Naïve versus ethanol-withdrawn rats. The place conditioning score was significantly correlated with %MPE with intra–lateral habenula DNQX (D) and CPZ (E) in EtOH-WD rats.