Table 1.
Functional properties of mouse DRG neurons and DEG/ENaC subunits expressed individually and in combination (in COS-7 cells)
| Amplitude (nA at pH 5) | Half-maximum pH activation | τ desensitization (sec) | τ recovery (sec, at pH 7.4) | |
|---|---|---|---|---|
| DRG neurons | ||||
| Wild-type | 4.1 ± 0.45 | 6.2 | 0.15 ± 0.01 | 0.42 |
| ASIC null | 1.4 ± 0.18* | 6.2 | 0.20 ± 0.02 | 0.20 |
| BNC1 null | 3.9 ± 1.00 | 6.6 | 0.15 ± 0.01 | 0.68 |
| DRASIC null | 2.66 ± 0.40* | |||
| DEG/ENaC subunits expressed individually | ||||
| DRASIC | 6.6 | 0.32 ± 0.02* | 0.40 | |
| ASICα | 6.8 | 4.0 ± 0.35* | 11 | |
| ASICβ | 6.2 | 1.3 ± 0.20* | 4.4 | |
| BNC1a | 4.9 | 2.8 ± 0.55* | 0.60 | |
| Coexpressed DEG/ENaC subunits | ||||
| DRASIC + ASICα | 6.6 | 0.14 ± 0.01 | 0.64 | |
| DRASIC + BNC1a | 6.1 | 0.26 ± 0.02* | 0.08 | |
| ASICα + BNC1a | 6.1 | 0.90 ± 0.20* | 0.63 | |
| DRASIC + ASICα + BNC1a | 6.4 | 0.18 ± 0.02 | 0.32 |
Values without standard errors are derived from curve fits of the means (n = 3–14 for each data point on the curves). Current amplitude at pH 5 (n = 22–65); τ desensitization at pH 6, except BNC1a is at pH 4 (n = 5–29). Asterisks denote statistical differences from wild-type DRG for data with standard errors of the mean (P < 0.01, two-tailed t test).