Table 1

Dopamine-stimulated adenylyl cyclase activity in PC2 cells expressing D1A dopamine receptors

Adenylyl Cyclase Activity
UntransfectedTransfected
pmol/min/mg
Basal14.5  ± 0.622.2  ± 0.71-a
Dopamine 100 μM15.1  ± 0.945.4  ± 6.51-b 1-c
SCH23390 10 μM + Dopamine 100 μM14.9  ± 0.823.8  ± 1.91-a 1-d

Membranes prepared from PC2 cells transfected with or without plasmids containing D1A dopamine receptors cDNA were incubated with 100 μM dopamine at 30°C for 10 min in the presence of 1 μCi [α-32P]ATP. Antagonism of dopamine-stimulated adenylyl cyclase activity was carried out by preincubating membranes with 10 μM SCH23390 for 10 min. The results are presented as mean ± S.E. obtained from four to six independent experiments.

    • 1-a p < .05 compared with the untransfected group.

    • 1-b p < .01 compared with the untransfected group.

    • 1-c p < .01 compared with basal activity.

    • 1-d p < .05 compared with dopamine alone.