Fig. 3.

Detailed analysis of low-dose morphine-induced behavioral changes. Three distinct animal behavior (A. Moving time, B. Clockwise (CW) rotation time, C. Counter-clockwise (CCW) rotation time) were recorded after a single-dose of morphine (5 mg/kg, s.c.) in 8 and 24 week old rats and analyzed using ActiMot software (TSE Systems). Measurements were taken prior to drug administration (basal), 30 and 180 min post-administration, as described in Section 2. Differences between the 30 min time point and the basal or 180 min time points were significantly different (*p<0.05, ***p<0.001 and ****p<0.0001, using repeated measure one-way ANOVA with Sidak's multiple comparison post hoc test). Likewise, significant differences against 8 week old animals were observed for some time points (^##p<0.01 and ^###p<0.001, using non-repeated measure one-way ANOVA with Sidak's multiple comparison post hoc test). All data are presented as mean±SEM, n=5 per group.