Table 1.
Receptor binding data of the peptide-derivatives 1 a–d, 2 a, 2 b and 3 for the human NTS1 and NTS2 receptor in comparison with the reference agent NT(8–13) and 22.
| Compd | Sequence | Ki [nm][a] | Selectivity | |
|---|---|---|---|---|
| NTS1[b] [3H]neurotensin | NTS2[c] [3H]NT[8-13] | Ratio Ki [NTS1]/Ki [NTS2] | ||
| NT(8–13)[d] | 0.24±0.024 | 1.2±0.17[e] | 0.20 | |
| 22[d] |  |
31 000±7000 | 8.0±0.94 | 3900 |
| 1 a |  |
1700±780[f] | 2500±1800[f] | 0.68 |
| 1 b |  |
2500±490[f] | 3600±1500[f] | 0.69 |
| 1 c |  |
79 000±21 000 | 5600±810 | 14 |
| 1 d |  |
19 000±2400 | 5400±2200 | 3.5 |
| 2 a |  |
130±36 | 4.8±1.1 | 27 |
| 2 b |  |
52 000±12 000 | 83±19 | 630 |
| 3 |  |
31 000±18 000 | 520±170 | 60 |
[a] Ki values in [nm±SEM] are the means of 3–9 individual experiments each done in triplicate. [b] Membranes from CHO cells stably expressing human NTS1. [c] Homogenates from HEK 293 cells transiently expressing human NTS2. [d] Data from ref. 7. [e] KD value. [f] Ki values in [nm±SD] are the means of two individual experiments each done in triplicate.