TABLE 2

Agonist dissociation constants for recombinant A2BARs determined in radioligand binding assays

Ki values obtained from competition binding experiments using [3H]MRS 1754. All values are the mean ± S.E. of three to five assays.




R1

R2



Dog

Rabbit

Mouse

Ki Ratio*
μM
Adenosine derivatives
    NECA Embedded Image Embedded Image Embedded Image 3.01 ± 0.46 2.60 ± 0.65 1.01 ± 0.19 3.0(D/M)
    R-PIA Embedded Image Embedded Image 34.9 ± 4.7 46.6 ± 12.5 28.3 ± 6.9 1.6(R/M)
    IB-MECA Embedded Image Embedded Image 26.6 ± 2.3 25.5 ± 3.8 12.4 ± 1.5 2.1(D/M)
6-Amino-3,5-dicyano-4-phenylpyridine derivatives
    Compound 1 Embedded Image Embedded Image Embedded Image
72.1 ± 8.6 51.3 ± 3.7 45.4 ± 5.6 1.6(D/M)
    Compound 2 Embedded Image Embedded Image 67.2 ± 8.2 43.6 ± 10.7 46.4 ± 3.9 1.5(D/R)
    Compound 3 Embedded Image Embedded Image 0.20 ± 0.08 0.27 ± 0.11 0.10 ± 0.02 2.7(R/M)
    Compound 4 (BAY 60-6583)
Embedded Image
Embedded Image
0.75 ± 0.11
0.34 ± 0.07
0.33 ± 0.08
2.3(D/M)
  • * Ratio of species with highest Ki/species with lowest Ki (D, R, and M denote dog, rabbit, and mouse, respectively).