Table 1.
Comparison of properties of dKv3.1 with native IKur,d and with other cardiac clones having similar kinetics
| IKur,d | dKv3.1 | Kv1.5 | Kv1.2 | Kv2.1 | Kv3.1 | |
|---|---|---|---|---|---|---|
| Activation | ||||||
| V½ (mV) | 6.9 ± 1.9 | 1.8 ± 0.6 | −14 ± 4 | −27 ± 6 | 2.1 ± 4.2 | 16 ± 1 |
| k (mV) | 9.2 ± 2.2 | 7.8 ± 0.5 | 5.9 ± 0.9 | 13 ± 2 | 17.4 ± 1.3 | 9 ± 4 |
| τ (ms, −10 to +50 mV) | 19.2–1.7 | 19.1–2.7 | 10–2 | 6.3 | 39–11 | 17.7–1.9 |
| Deactivation | ||||||
| τ (ms at −60 mV) | 3.8 | 3.5 | 23 | 23 | 4.3 | 1.4 |
| Inactivation | ||||||
| τ | τ1 = 0.6 s | τ1 = 0.7 s | τ1 = 1.32 s | NR | τ = 4 s (0 mV) | NR |
| τ2 = 5.6 s | τ2 = 8.9 s | τ2 = 16.77 s | — | τ = 7 s (+80 mV) | — | |
| Rectification | Inward | Inward | Outward | NR | NR | Inward |
| Pharmacological properties | ||||||
| 4AP (IC50μmol l−1) | 5.3 | 14.4 | 181 | 590 | 500 | 49 |
| TEA (IC50 mmol l−1) | 0.3 | 0.13 | 330 | 0.56 | 5.6–10 | 0.2 |
| DTX (IC50 nmol l−1) | NS | NS | > 1000 | 0.4–17 | NR | NS |
NR, not reported; NS, not sensitive. Results for IKur,d are from Yue et al. 1996; results for dKv3.1 are from the present study; and results for Kv1.5, Kv1.2, Kv2.1 and Kv3.1 are from: Grissmer et al. 1992, 1994; Rettig et al. 1992; Castellano et al. 1997; Harvey, 1997; Murakoshi et al. 1997; Feng et al. 1998; Klemic et al. 1998; Mathie et al. 1998.