Comparison of binding affinities of ABT-288, ABT-239, and ciproxifan at histamine receptors
Data are expressed as the mean Ki (nM) with the associated 95% confidence limit in parentheses (n = 3–36 independent experiments performed in duplicate). H3 receptors were stably expressed in C6 cells; H1, H2, and H4 receptors were stably expressed in HEK cells.
| ABT-288 | ABT-239 | Ciproxifan | |
|---|---|---|---|
| Human H3 | 1.90 (1.07–3.36) | 0.45 (0.37–0.54) | 62.5 (50.6–77.2) |
| Human brain cortex H3 | 0.64 (0.4–1.04) | 4.61 (3.46–6.13) | 89.4 (63.5–125.7) |
| Rat H3 | 8.15 (4.74–14.0) | 1.24 (1.00–1.53) | 0.42 (0.29–0.62) |
| Rat brain cortex H3 | 8.09 (4.69–14.0) | 3.23 (2.70–3.86) | 0.59 (0.49–0.73) |
| Mouse brain cortex H3 | 10.0 (2.32–43.2) | 3.59 (2.64–4.90) | 0.48 (0.36–0.64) |
| Human H1 | >10,000 | 1640 (1290–2080) | >10,000 |
| Human H2 | >10,000 | 6,720 (5070–8900) | >10,000 |
| Human H4 | >10,000 | >10,000 | 1250 (640–2430) |