Table 1.

Effects of D2 receptor agonist and D2 receptor antagonist on D1-stimulated increase in NR1 phosphorylation in nucleus accumbens slices

Treatment	[32P]phosphate-labeled NR1 (%)
	(−)Raclopride	(+)Raclopride
Control	50  ± 4	44  ± 19
D1 agonist	100	88  ± 6
D1 + D2	49  ± 4*	98  ± 16
D2 agonist	43  ± 7

Nucleus accumbens slices were prelabeled with [³²P]phosphate. Slices were incubated for a total of 15 min. Raclopride (1 μm) was added at 0 min, and D1 agonist (SKF81297, 1 μm) and D2 agonist (quinpirole, 1 μm) were added at 10 min. [³²P]phosphate incorporation into NR1 was determined as described in Materials and Methods. Data were calculated as percentage of radioactivity in slices incubated with D1 agonist and represent means ± SEM (*p < 0.05, compared with D1 agonist alone, Mann-Whitney U test; n = 4–10 experiments).