Table 3.

Lower lip retraction score as a function of 8-OH-DPAT for the Zn, WAY-100635 and control groups

	Mean ± LLR score
Treatment (mg/kg)	(A) VEH	(B) 8-OH-DPAT 1 mg/kg
VEH	0.0 ± 0.0	2.25 ± 0.46###
Zn 2	0.0 ± 0.0	1.17 ± 0.98*
Zn 5	0.0 ± 0.0	0.46 ± 0.75***
WAY 100635 0.1	0.0 ± 0.0	0.67 ± 0.76**

(A) Each animal was scored for LLR three times, 15, 30 and 45 min after the administration of Zn as follows: 0 = lower incisors not visible, 0.5 = partly visible and 1 = completely visible. The maximum total score was 3/rat. Zn was administered at doses of 2 and 5 mg Zn/kg. (B) The effect of Zn and WAY-100635 on the LLR induced by 8-OH-DPAT was scored using the same scale. Zn and WAY-100635 was administered 45 min before 8-OH-DPAT and the animals were scored 15, 30 and 45 min after 8-OH-DPAT treatment. The values represent the mean ± SEM (n = 8–10 rats per group)

^### p < 0.01 vs. VEH; *p < 0.05, **p < 0.01 and ***p < 0.001 vs. 8-OH-DPAT. Statistical analysis was performed using one-way ANOVA followed by Dunnett’s post hoc test