Table 1.

Names/sequences, binding-, activity-, and MPE values of Aba-peptidomimetics versus MT-II³⁵–³⁷

Name	Sequence	hMC1R			hMC3R			hMC4R			hMC5R
		IC50 (nM)	EC50 (nM)	Max effect (%)	IC50 (nM)	EC50 (nM)	Max effect (%)	IC50 (nM)	EC50 (nM)	Max effect (%)	IC50 (nM)	EC50 (nM)	Max effect (%)
Aba-1	Ac-Nle-Asp-Aba-D-Phe-Arg-Trp-Lys-NH2	>10,000	>10,000	0	>10,000	>10,000	0	>10,000	>10,000	0	>10,000	>10,000	0
Aba-2	Ac-Nle-c[Asp-Aba-D-Phe-Arg-Trp-Lys]-NH2	>10,000	>10,000	0	50 ± 6	>10,000	0	>10,000	>10,000	0	2,900 ± 300	>10,000	0
Aba-3	Ac-Nle-c[Asp-Aba-p-Cl-D-Phe-Arg-Trp-Lys]-NH2	>1,000	900 ± 100	60	29 ± 3	>1,000	55	2,000 ± 200	3,200	33	123 ± 13	180 ± 20	45
Aba-4	Ac-Nle-c[Asp-Aba -D-Nal-Arg-Trp-Lys]-NH2	580 ± 70	>2,500	60	43 ± 5	>10,000	0	1700 ± 200	>10,000	0	87 ± 10	>10,000	0
MT-II	Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-NH2	0.2 ± 0.01	0.3 ± 0.04	100	1.25 ± 0.2	1.85 ± 0.2	100	1.07 ± 0.3	2.87 ± 0.52	100	7.47 ± 0.23	3.3 ± 0.7	100

IC₅₀, concentration of compound at 50% specific binding. Values are means of three experiments; standard deviation is given.³⁷

EC₅₀, effective concentration of compound that was able to generate 50% maximal intracellular cAMP accumulation. Compounds were tested at a range of concentrations from 10⁻¹⁰ to 10⁻⁵ M.³⁸