Table 2.

The mean ratios of the distance traveled in the inner to outer zone in male and female rats in 30 min testing period.

Test day	CON (SEM)	OXY-L (SEM)	OXY-H (SEM)
Male
1	0.13 (0.01)	0.19 (0.09)	0.13 (0.01)
2	0.15 (0.01)	0.27 (0.07)	0.13 (0.01)
Estimated mean day 1 and 2	0.14 (0.01)	0.24 (0.07)*	0.12 (0.01)
Female
1	0.13 (0.01)	0.10 (0.04)	0.17 (0.03)
2	0.14 (0.02)	0.11 (0.04)	0.17 (0.02)
Estimated mean day 1 and 2	0.13 (0.01)	0.10 (0.05)	0.17 (0.02)

*p < 0.05 {the estimated mean ratio of distance traveled in the inner to outer zone of male OXY-L rats which was 0.245, was estimated to be 0.095 larger than that of the CON [95% CI: (0.027, 0.162), p = 0.008], and 0.112 larger than for OXY-H [95% CI: (0.042, 0.1830, p = 0.002)]}.

CON, control; OXY-H, oxycodone high dose; OXY-L, oxycodone low dose.