Table 2.
Comparison of affinities of adenine and selected compounds for the rat adenine receptor and bacterial binding sites determined in radioligand binding studies
| Compound | Achromobacter xylosoxidans (intact bacteria) | Rat brain cortical membranes |
|---|---|---|
| IC50 ± SEM [μM]a (% inhibition ± SEM at 10 μM) | Ki ± SEM [μM]a (% inhibition ± SEM at 100 μM) | |
| Adenine | 0.0138 ± 0.0027b | 0.0299 ± 0.0034c |
| 2-Fluoroadenine | 32.1 ± 3.0 | 0.62 ± 0.14c |
| 2-Hydroxyadenine | ≫10 (7 ± 15)d | 29.4 ± 6.4 |
| 2,6-Diaminopurine | ≫10 (3 ± 8)d | 4.95 ± 0.75 |
| 1,N6-Ethenoadenine | ca. 10 (53 ± 6)d | 34.4 ± 8.1 |
| Hypoxanthine | 0.0591 ± 0.0196 | 45.0 ± 19.4 |
| Uracil | ≫10 (6 ± 1) | ≫100 (−6 ± 2) |
| Xanthine | >10 (17 ± 6) | >100 (23 ± 7) |
| Uridine | ≫10 (5 ± 5)d | ≫100 (−9 ± 3) |
| Adenosine | ≫10 (12 ± 9)d | 19.4 ± 6.3c |
aResults are from three independent experiments performed in triplicate, unless otherwise noted
bResults are from eight independent experiments performed in triplicate
cKi values and % inhibition values are from [7]
dResults from two independent experiments performed in triplicate