TABLE 2

Activation of hD₃, hD_2L, and hD_2S receptors by S32504 and ropinirole as determined by measures of total G-protein activation ([³⁵S]GTPγS binding), Gα_i3 activation (immunoprecipitation coupled to SPA detection), and MAP kinase phosphorylation (immunoblot) Data are means ± S.E.M. of ≥3 determinations, each performed in triplicate.

	hD₃											hD_2L				hD_2S Total G-Protein
	Total G-Protein			Gα_i3			MAP Kinase			Total G-Protein			Gα_i3		MAP Kinase	hD_2S Total G-Protein
	pEC₅₀	% E_max	pEC₅₀	% E_max	pEC₅₀	% E_max	pEC₅₀	% E_max	pEC₅₀	% E_max	pEC₅₀	% E_max	pEC₅₀	% E_max
S32504	8.66 ± 0.20	74 ± 3	8.64 ± 0.07	68 ± 2	8.45 ± 0.15	85 ± 5	6.71 ± 0.02	50 ± 3	6.63 ± 0.09	51 ± 1	8.59 ± 0.15	100 ± 6	6.39 ± 0.07	87 ± 1
Ropinirole	7.56 ± 0.09^a	59 ± 4^a	8.09 ± 0.04	60 ± 3	8.51 ± 0.11	80 ± 8	6.38 ± 0.09^a	52 ± 3^a	6.48 ± 0.06	55 ± 5	8.21 ± 0.07	98 ± 2	6.18 ± 0.10^a	108 ± 2^a

pEC₅₀, -log (effective concentration₅₀); h, human.
↵ a From Millan et al. (2002)