Fig. 3

Participation of the DRN in MCS-induced antinociception. Quantification of Egr-1 (A) and 5HT (B) IR in the DRN of naive (without surgical intervention), sham (with epidural electrodes but without stimulation) and stimulated (MCS, 1.0 V/60 Hz/210 µs, 15 min) rats. Values represent the mean ± SEM (n = 5 animals per group). *p < 0.05 and **p < 0.01 in comparison to the naive group, after Bonferroni’s post hoc test. Photomicrographs illustrating the 5HT-IR in the DRN of sham (C) and stimulated (D) rats. 5HT serotonin, DRN dorsal raphe nucleus, IR immunoreactivity, MCS motor cortex stimulation. Scale bars: 200 µm