Table 1.

Comparison of Agonist Activities

	[35S]GTP-γ-S		Gα 16-h κOR Calcium Flux
Compound	κ EC50 ± SE, nM	κ Emaxa ± SE	EC50 ± SE, nM	Emaxa ± SE
(-)-U69,593	330 ± 70	100 ± 7	2.25 ± 0.82	100 ± 12
2a	45 ± 10b	108 ± 4b	1.24 ± 0.56	118 ± 3
3a	280 ± 60	49 ± 5	3.34 ± 0.11	93 ± 3
5	2700 ± 400	95 ± 12	NTc	NTc

^aE_max is relative to the maximum stimulation of binding observed with U69,593 run in parallel with the test compounds

^bValues from reference ¹⁰

^cNot tested, no experiments were done to determine value