Glycine dose–response properties obtained on coexpression of different ratios of the NR1 wild-type and NR1Q387K mutant subunits with NR2B
| cRNAs injected | EC50(μm) | nH | Imax(nA) | Fractional current (%) | n |
|---|---|---|---|---|---|
| NR1 | 0.52 ± 0.28 | 1.6 ± 0.2 | 3600 ± 1000 | 9 | |
| NR1 + NR1Q387K (5:1) | 2400 ± 1100 | 3 | |||
| HA-component | 0.7 ± 0.4 | 1.8 ± 0.3 | 80 ± 9 | ||
| IMA-component | 38 ± 21 | 1.5 ± 0.5 | 20 ± 9 | ||
| LA-component | n.d. | n.d. | |||
| NR1 + NR1Q387K (1:1) | 1700 ± 700 | 4 | |||
| HA-component | 0.8 ± 0.5 | 1.8 ± 0.4 | 24 ± 6 | ||
| IMA-component | 51 ± 17 | 1.4 ± 0.3 | 48 ± 9 | ||
| LA-component | 4900 ± 2200 | 1.7 ± 0.6 | 28 ± 7 | ||
| NR1 + NR1Q387K (1:5) | 1900 ± 800 | 3 | |||
| HA-component | n.d. | n.d. | |||
| IMA-component | 76 ± 42 | 1.6 ± 0.6 | 26 ± 13 | ||
| LA-component | 8000 ± 3200 | 1.2 ± 0.2 | 74 ± 13 | ||
| NR1Q387K | 7400 ± 2100 | 1.5 ± 0.3 | 3500 ± 1400 | 4 |
NR1 wild-type and NR1 mutant cRNAs were coinjected with the NR2B cRNA into Xenopus oocytes at the RNA ratios indicated in parentheses, and glycine dose–responses of the resulting receptors were analyzed by voltage-clamp recording as detailed in Materials and Methods. EC50 values ± SD were calculated from dose–response curves obtained from three to nine oocytes, each.Imax values were determined in the presence of saturating concentrations of l-glutamate.nH, Hill coefficient; n.d., not detectable. HA, High-affinity; IMA, intermediate-affinity; LA, low-affinity components of mixed receptor populations.