Table 2. Effect of dopamine receptor antagonists on the increase in locomotor activity induced by 7α-hydroxypregnenolone.

Treatment	Locomotor activity, line crossings per 30 min
Vehicle	25.9 ± 4.1
7α-Hydroxypregnenolone	55.6 ± 6.2*
7α-Hydroxypregnenolone + haloperidol	20.8 ± 2.2†
7α-Hydroxypregnenolone + sulpiride	25.0 ± 4.5†
7α-Hydroxypregnenolone + SCH23390	51.3 ± 11.8*

Newts (n = 7 per each treatment) in the nonbreeding period (November and December) were used. The dopamine D₁-like receptor antagonist, SCH23390 (1 μg, n = 7), or dopamine D₂-like receptor antagonist, haloperidol (1 μg, n = 7) or sulpiride (1 μg, n = 7) was injected i.p. 60 min prior to an i.c.v. injection of 7α-hydroxypregnenolone (1 ng). Results were expressed as the mean ± SEM total number of crossings. *, P < 0.01 vs. vehicle. †, P < 0.01 vs. 1 ng of 7α-hydroxypregnenolone alone by one-way ANOVA, followed by Duncan's multiple range test.