Table 1 Affinities of multiple chimeric melanocortin receptors. Affinities (pK ± standard deviation, SD) of multiple chimeric melanocortin receptors for α-MSH, NDP-MSH and [¹²⁵I]-NDP-MSH determined by radioligand binding.

A

B

C

¹²⁵I-NDP-MSH

NDP-MSH

α-MSH

1

MC₁

wt.

MC₁

MC₁

MC₁

9.96^a

10.34^a

9.68^a

2

MC₃

wt.

MC₃

MC₃

MC₃

9.40^a

9.31^a

7.27^a

3

MC₄

wt.

MC₄

MC₄

MC₄

8.64^a

8.73^a

5.69^a

4

MC₅

wt.

MC₅

MC₅

MC₅

8.54^a

8.58^a

5.30^a

5

F134

F

MC₁

MC₃

MC₄

8.58 ± 0.17

10.37 ± 0.01

7.70 ± 0.14

6

F153

F

MC₁

MC₅

MC₃

8.88 ± 0.16

10.38 ± 0.12

7.80 ± 0.56

7

F354

F

MC₃

MC₅

MC₄

8.80 ± 0.16

8.66 ± 0.48

5.72 ± 0.65

8

F413

F

MC₄

MC₁

MC₃

8.62 ± 0.16

8.64 ± 0.16

6.21 ± 0.42

9

F435

F

MC₄

MC₃

MC₅

8.96 ± 0.08

8.81 ± 0.14

6.39 ± 0.40

10

F451

F

MC₄

MC₅

MC₁

9.06 ± 0.31

8.54 ± 0.26

6.33 ± 0.43

11

F514

F

MC₅

MC₁

MC₄

9.19 ± 0.21

8.45 ± 0.11

5.11 ± 0.14

12

F531

F

MC₅

MC₃

MC₁

8.67 ± 0.48

10.85 ± 0.28

5.33 ± 0.08

13

F543

F

MC₅

MC₄

MC₃

9.24 ± 0.25

9.51 ± 0.50

6.39 ± 0.50

14

S134

S

MC₁

MC₃

MC₄

9.30 ± 0.26

9.98 ± 0.16

9.02 ± 0.22

15

S354

S

MC₃

MC₅

MC₄

8.81 ± 0.18

8.62 ± 0.37

4.88 ± 0.25

16

S451

S

MC₄

MC₅

MC₁

9.06 ± 0.31

9.35 ± 0.36

6.10 ± 0.16

17

S514

S

MC₅

MC₁

MC₄

9.19 ± 0.21

10.04 ± 0.31

7.31 ± 0.38

18

S531

S

MC₅

MC₃

MC₁

8.96 ± 0.35

9.18 ± 0.65

7.57 ± 0.19