Voltage-dependent block of NR1/NR2A receptors by N1-DnsSpm
| Subunit combination | IC50 at −70 mV2-a | Kd (0)2-b | zδ2-b | No. of oocytes |
|---|---|---|---|---|
| μm | μm | |||
| Wild-type NR1/NR2A | 0.38 | 779 ± 272 | 2.58 ± 0.10 | 14 |
| NR1(N616Q)/NR2A | 5.7 | 1351 ± 1702-c | 1.81 ± 0.042-d | 21 |
| NR1(N616G)/NR2A | 0.01 | 45 ± 72-c | 2.71 ± 0.04 | 15 |
| NR1/NR2A(N615G) | 0.02 | 29 ± 52-c | 2.59 ± 0.06 | 12 |
↵2-a Data for the IC50 values of N1-DnsSpm are from Table 4.
↵2-b Values for Kd (0) and zδ were derived using text eq. 2 with data from voltage ramps (−100 to +40 mV over 6 or 12 sec or −150 to +40 mV over 6 sec), using data from the part of the I-V relationship that showed a steep voltage dependence. The concentrations of N1-DnsSpm that were used were 0.3–2 μM for NR1/NR2A, 2 or 30 μm for NR1(N616Q)/NR2A, and 0.1 μm for NR1(N616G)/NR2A and NR1/NR2A(N615G). For NR1(N616Q)/NR2A the values ofKd (0) (1597 ± 279 μm) and zδ (1.73 ± 0.03) determined in experiments with 30 μm N1-DnsSpm using ramps from −100 to +40 mV were similar to the values of Kd (0) (1128 ± 190 μm) and zδ (1.88 ± 0.06) determined in experiments with 2 μm N1-DnsSpm using ramps from −150 to +40 mV.
↵2-c p < 0.05,
↵2-d p < 0.01 compared with wild-type NR1/NR2A (one-way ANOVA with post hoc Dunnett’s test).