Table 1.
Inhibition by ADP and expression levels of wild-type and mutant P2Y12 receptor constructs expressed in CHO-K1 cells.
| Construct | Max. inhibition by ADP (% of control) | IC50 ADP(μM) | Expression levels (% of wild-type) |
|---|---|---|---|
| Wild-type | 85.37 ± 2.14 (3) | 0.25±0.04 | 100 ± 1.09 (14) |
| F104S | 77.7 ± 1.12 (3) | 0.06±0.01a | 103.21 ± 1.78 (12) |
| Y109S | 31.96 ± 0.15b (3) | 0.17±0.09 | 120.87 ± 0.7 (13) |
| F198P | 40.37 ± 10.64b(3) | 0.15±0.05 | 143.46 ± 0.75 (15) |
| H253S | 62.21 ± 1.93 (3) | 0.35±0.21 | 105.39 ± 0.99 (24) |
| R256T | 79.53 ± 4.83 (3) | 0.29±0.05 | 123.28 ± 0.75 (26) |
| R256Q | 75.32 ± 6.91 (3) | 0.57±0.03a | 106.19 ± 0.72 (11) |
| R265W | 58.01 ± 3.08a (3) | 0.45±0.21 | 87.38 ± 0.90 (8) |
| R256QR265W | 56.68 ± 6.32a (3) | 6.46±0.19b | 148.85 ± 0.81 (20) |
| S288P | 68.89 ± 6.24 (3) | 0.04±0.01a | 120.17 ± 0.97 (16) |
Mean ± S.E.M. of (n) experiments.
a
P<0.01,
b
P<0.001, significant differences vs. values determined at wild-type P2Y12 receptors (student t-test). Expression levels were estimated by averaging fluorescence values from the membrane regions of cells after immunofluorescence staining with a monoclonal antibody against the HA-tag.