Table 2.

Effects of agonists on inward currents and cAMP responses initiated in Xenopus oocytes expressing theDrosophila DopR99B receptor

Agonists (10 μm)Percentage of inward current*response to 1 μm dopamine (n)Percentage of cAMP response to 10 μm dopamine (n)Receptor type specificity
(±)-6-Chloro-APB89.4  ± 3.8 (6)1.9  ± 1.2 (10)D1-like
R(+)-6-Bromo-APB73.3  ± 9.1 (6)3.7  ± 2.9 (10)D1-like
(±)-6-Chloro-PB19.6  ± 7.7 (5)13.0  ± 7.6 (10)D1-like
Quinelorane11.3  ± 3.0 (8)3.2  ± 2.1 (10)D2-like
(±)-Bromocriptine7.5  ± 2.6 (5)4.3  ± 1.6 (10)D2-like
Quinpirole4.1  ± 2.3 (6)2.0  ± 0.8 (10)D2/D3
R(+)-SKF-383931.8  ± 1.2 (6)5.3  ± 1.5 (10)D1-like
(±) Isoproterenol1.3  ± 0.9 (6)3.5  ± 1.5 (10)β-Adrenergic
PD-128,907     0 (6)1.3  ± 0.9 (10)D3
(±)-PPHT     0 (4)16.1  ± 6.5 (10)D2-like
  • The size of the inward current response to a 2 min pulse of agonist is expressed as a percentage ± SE of the response to a control dopamine pulse given to the same oocyte. The size of the cAMP response to a 30 min exposure to 10 μm agonist in the presence of 100 μm IBMX after a 30 min preincubation in the presence of 100 μm IBMX alone is expressed as a percentage ± SE of the response to a control dopamine exposure. All measurements were made 5 d after injection of oocytes with DopR99B cRNA.

  • * Data reproduced from Feng et al. (1996) for comparison.