Kd values for [3H] kainate and Ki values for displacement of [3H] kainate by DH and MSVIII-19 on kainate receptor mutants Kd values were determined by fitting curves with one-site binding (hyperbola). Kd values are presented as mean ± S.E.M. Ki values were calculated using Kd values in Table with the Cheng-Prusoff equation (Ki = IC50/(1 + [radioligand]/Kd). Ki values are mean with 95% confidence intervals in parentheses. IC50 values were obtained using a one-site competition fit using Prism 4 software. Values are in nanomolar, except for bold values, which are micromolar.
| Kd [3H]KA | Ki | ||
|---|---|---|---|
| DH | MSVIII-19 | ||
| GluR5 WT | 157 ± 35 | 3.1 (1.5–6.5) | 100 (65–155) |
| V685I | 25 ± 7.2* | 6.1 (5.2–7.3) | 4.4 (3.0–6.3) |
| L735F | 145 ± 78 | 5.9 (4.3–8.2) | 1.2 (0.6–2.6) |
| S741M | 43 ± 11* | 3.0 (1.9–4.9) | 2.6 (1.7–3.8) |
| V685I/ S741M | 15 ± 0.7* | 4.8 (3.5–6.6) | 26 (15–46) a |
| V685I/ L735F/ S741M | 27 ± 2.2* | 66 (38–116) | 72 (34–149) a |
| KA2 WT | 5.3 ± 4.1 | 1.8 (1.3–2.4) | >100 |
| I669V | 5.6 ± 0.5 | 18 (12–26) | 41 (26–65) a |
| F719L | 24 ± 9.9 | 81 (60–108) | >100 |
| M725S | 2.9 ± 0.6 | 5.2 (3.8–6.8) | 31 (23–42) a |
| I669V/ M725S | 12 ± 3.8 | 7.0 (5.5–8.8) | 4.0 (2.5–6.2) |
| I669V/ F719L/ M725S | 20 ± 4.2 | 29 (19–43) | 3.6 (2.6–5.1) |