TABLE 1.
Binding parameters of CCK1 receptor-based chimeric constructs expressed in CHO cells
| CCK1R-based chimeric receptors | Receptor abbreviations | 125I-BDZ-1 vs GI181771X Ki | 125I-BDZ-1 vs GI181771X Bmax | 125I-BDZ-2 vs GI181771X Ki | 125I-BDZ-2 vs GI181771X Bmax |
|---|---|---|---|---|---|
| nm | pmol/mg protein | nm | pmol/mg protein | ||
| CCK1R WT | CCK1R | 104.7 ± 19.6 | 41 ± 7 | NDBa | NDB |
| N2.61T | CCK1R TM2 | 89.0 ± 37.0 | 16 ± 5 | NDB | NDB |
| T3.28V, T3.29S | CCK1R TM3 | 6.3 ± 1.4b | 20 ± 7 | NDB | NDB |
| I6.51V, F6.52Y | CCK1R TM6 | 73.6 ± 7.9 | 80 ± 6b | NDB | NDB |
| L7.39H | CCK1R TM7 | 109.0 ± 43.9 | 36 ± 19 | NDB | NDB |
| N2.61T, T3.28V, T3.29S | CCK1R TM (2,3) | 6.3 ± 3.5b | 14 ± 5b | 11.9 ± 6.1 | 30 ± 6c |
| N2.61T, I6.51V, F6.52Y | CCK1R TM (2,6) | 19.9 ± 4.5b | 23 ± 6 | 111.6 ± 33.7c | 87 ± 44 |
| N2.61T, L7.39H | CCK1R TM (2,7) | 22.2 ± 5.7b | 29 ± 7 | 238.7 ± 28.9c | 87 ± 6c |
| T3.28V, T3.29S, I6.51V, F6.52Y | CCK1R TM (3,6) | 4.6 ± 2.8b | 5 ± 1b | NDB | NDB |
| T3.28V, T3.29S, L7.39H | CCK1R TM (3,7) | 9.4 ± 3.2b | 10 ± 4b | NDB | NDB |
| I6.51V, F6.52Y, L7.39H | CCK1R TM (6,7) | 1.4 ± 0.3b | 6 ± 2b | NDB | NDB |
| N2.61T, T3.28V, T3.29S, I6.51V, F6.52Y | CCK1R TM (2,3,6) | 1.4 ± 0.2b | 11 ± 2b | 45.6 ± 20.3c | 69 ± 18c |
| N2.61T, T3.28V, T3.29S, L7.39H | CCK1R TM (2,3,7) | 1.9 ± 0.5b | 11 ± 3b | 107.7 ± 44.2c | 79 ± 13c |
| N2.61T, I6.51V, F6.52Y, L7.39H | CCK1R TM (2,6,7) | 2.8 ± 0.4b | 12 ± 2b | 109.5 ± 34.2c | 39 ± 9c |
| T3.28V, T3.29S, I6.51V, F6.52Y, L7.39H | CCK1R TM (3,6,7) | 2.3 ± 0.1b | 11 ± 1b | NDB | NDB |
| N2.61T, T3.28V, T3.29S, I6.51V, F6.52Y, L7.39H | CCK1R TM (2,3,6,7) | NDB | NDB | 70.4 ± 16.3c | 83 ± 20c |
| CCK2R WT | CCK2R | 5.1 ± 1.6 | 6 ± 2 |
a NDB, no detectable binding.
b p < 0.05 compared to values for wild-type CCK1R.
c p < 0.05 compared to values for wild-type CCK2R.