Table 1.
Properties of immature and mature IHCs from Cx30 and Cx26 knock-out micea
| Immature Cx30 KO(P3) | Adult Cx30 KO (P16-P18) | Cx26Sox10-Cre (P25) | Cx30 Δ/Δ (P25) | ||||
|---|---|---|---|---|---|---|---|
| +/+ | −/− | +/+ | −/− | +/+ | −/− | Δ/Δ | |
| Resting potential (mV) | −57.7 ± 1.6 (4) | −58.5 ± 0.5 (4) | −74.4 ± 1.1 (11) | −69.3 ± 1.2 (11) | −69.2 ± 1.9 (3) | −73.5 ± 1.4 (8) | −73.5 ± 2.6 (5) |
| IK1 at −124 mV (pA) | −120 ± 31 (4) | −126 ± 25 (9) | — | −121 ± 13 (9) | — | ? | — |
| IK at 0 mV (nA) | 4.5 ± 0.3 (5) | 3.9 ± 0.2 (9) | 12.8 ± 1.5 (10) | 10.4 ± 0.8 (9) | 13.1 ± 1.5 (3) | 10.7 ± 1.0 (8) | 13.5 ± 0.4 (6) |
| IK,f at −25 mV (nA) | — | — | 1.8 ± 0.3 (10) | — | 3.7 ± 0.2 (3) | 1.4 ± 0.2 (8) | 2.8 ± 0.2 (6) |
| IK,n at −124 mV (pA) | — | — | 98 ± 67 (7) | — | 302 ± 17 (3) | 144 ± 17 (8) | 349 ± 26 (5) |
-
↵ap Data are mean ± SEM. Values in parentheses are number of hair cells. IK1, Inward rectifier K+ current (Marcotti et al., 1999); IK, delayed rectifier K+ current (Marcotti et al., 2003); IK,n, negatively activated K+ current carried by KCNQ4 channels (Marcotti et al., 2003); IK,f, Ca2+-activated K+ current (Kros et al., 1998); −, not present; ?, size of IK1 was difficult to quantify because, if present, it was masked by IK,n.
