Table 2.

In vitro functional activity of POMO at the opioid receptors.

	Bioassaya		[35S]GTPγS Bindingb
	IC50 (nM)		MOR		DOR		KOR
	GPI	MVD	EC50 (nM)	% stim.	EC50 (nM)	% stim.	EC50 (nM)	% stim.
14-OMO	2.0 ± 0.3c	30.5 ± 5.5c	1.62 ± 0.48	97 ± 6	43.8 ± 11.7	106 ± 1	144 ± 32	65 ± 7
POMO	1.2 ± 0.21*	0.03 ± 0.0013***	0.082 ± 0.017**	100 ± 8	0.28 ± 0.14**	91 ± 8	0.38 ± 0.13**	39 ± 5
Morphine	311 ± 29c	1600 ± 121c	34.4 ± 5.1d	89 ± 17d	668 ± 65d	109 ± 14d	710 ± 23d	76 ± 2d
Dermorphin	1.3 ± 0.27	18 ± 0.31
Deltorphin I	1239 ± 132	0.19 ± 0.03
DAMGO			14.7 ± 1.9	100
DPDPE					1.26 ± 0.76	100
U69,593							16.7 ± 3.0	100

^aFunctional bioactivity was determined using GPI and MVD preparations. ^b[³⁵S]GTPγS binding assays were performed with membranes from CHO stably expressing human opioid receptors. Percentage stimulation (% stim.) is presented relative to the reference full agonists DAMGO (MOR), DPDPE (DOR), or U69,593 (KOR). ^cData from Lattanzi et al. (2005). ^dData from Ben Haddou et al. (2014). Values are means ± SEM of at least three experiments. ^∗P < 0.05, ^∗∗P < 0.01, ^∗∗∗P < 0.001, vs. 14-OMO (unpaired t-test).