. Author manuscript; available in PMC: 2009 Oct 23.

Published in final edited form as: J Med Chem. 2008 Sep 27;51(20):6334–6347. doi: 10.1021/jm800389v

Table 7.

Functional assay result for bifunctional peptide ligands at opioid and Substance P receptors

No	Opioid agonist		Substance P GPI

	MVD (δ), IC₅₀ (nM)^a	GPI (μ), IC₅₀ (nM)^a	antagonist, Ke (nM)^b
1^c	22 ± 1.2	360 ± 130	25 ± 8.8
2	15 ± 2.0	490 ± 29	10 ± 2.1
3	4.8 ± 0.35	61 ± 9.6	9.9 ± 2.8
Biphalin	2.7 ± 1.5	8.8 ± 0.3
4			250 ± 87

Concentration at 50% inhibition of muscle concentration at electrically stimulated isolated tissues.

Inhibitory activity against the Substance P induced muscle contraction in the presence of 1 μM naloxone, Ke: concentration of antagonist needed to inhibit Substance P to half its activity.

See a reference.³⁸