Figure 7.
The effect of injection of 20 μl of 10% formalin on licking the injected paw (pain-related behavior) in the African naked mole-rat, 30 min after pre-treatment with drugs. Data are presented as mean±standard error of the mean (SEM). A) Pain-related behavior 30 min after pre-treatment with saline (n=8) and epibatidine at 0.5 μg/kg bw (EPI 0.5), 1 μg/kg bw (EPI 1), 2 μg/kg bw (EPI 2), and 3 μg/kg bw (EPI 3) (all n=6). Two-way ANOVA with Bonferroni's post-test was used to demonstrate differences in pain-related behavior between groups. Significant difference a, between saline and EPI 0.5; b, between saline and EPI 1; c, between saline and EPI 2; d, between saline and EPI 3; e, between EPI 0.5 and EPI 1; f, between EPI 0.5 and EPI 2; g, between EPI 0.5 and EPI 3; and h, between EPI 1 and EPI 3. B: Pain-related behavior 30 min after pre-treatment with EPI 2 in co-administration with mecamylamine at 50 μg/kg bw (EPI 2 + MEC 50) (n=6), in comparison to treatment with saline (n=8), EPI 2, and mecamylamine 50 μg/kg alone (MEC 50) (n=6). Significant difference a, between saline and EPI 2; b, between MEC 50 and EPI 2; and c, between EPI 2 and EPI 2 + MEC 50. C: Pain-related behavior 30 min after pre-treatment with EPI 2 in co-administration with naloxone 2.5 at mg/kg (EPI 2 + NAL 2.5) (n=6), in comparison to treatment with saline, EPI 2, and naloxone 2.5 mg/kg alone (NAL 2.5) (n=6). Significant difference a, between saline and EPI 2; b, between saline and EPI 2 + NAL 2.5; c, between NAL 2 and EPI 2; and d, between NAL 2.5 and EPI 2 + NAL 2.5.