Fig. 5.

Electroencephalographic spectral parameters on the medial prefrontal cortex (FC) and the parietal cortex (PC) in rats treated with tramadol. The rats (n=6) were intraperitoneally administered saline, and tramadol 5, 10, 20 and 40 mg/kg, respectively (group 'Control', 'TRA5', 'TRA10', 'TRA20' and 'TRA40'). The changes of spectral edge frequency 95 (SEF95) and median power frequency (MPF) between groups were not significant, except in MPF of FC. Data were expressed as mean±S.D. Data were analyzed by two factor repeated measures ANOVA with time and treatment, and a Bonferroni test was used to analyze variables for time between groups. Statistical results were not marked in figure, but were described in text.