Table 5.
Modulation of NaV inactivation in Ins1 cells
| Monophasic | Biphasic | ||||||
|---|---|---|---|---|---|---|---|
| NaV current | Treatment | V h (mV) | k | V h1 (mV) | k 1 | V h2 (mV) | k 2 |
| NaV1.7 | Control | −96 ± 1 (5) | 8 ± 1 (5) | n/a | n/a | n/a | n/a |
| NaV1.7 | 100 nm BIM23056 | −90 ± 2 (5) | 8 ± 1 (5) | n/a | n/a | n/a | n/a |
| NaV1.7 | 10 nm PMA | −96 ± 4 (4) | 10 ± 1 (4) | n/a | n/a | n/a | n/a |
| Ins1 endogenous | Control | −94 ± 6 (2) | 10 ± 1 (2) | −94 ± 1 (2) | 10 ± 1 (2) | −45 ± 5 (2) | 4 ± 1 (2) |
| Ins1 endogenous | 10 nm PMA (chronic) | −91 ± 2 (6) | 11 ± 1 (6) | −92 ± 2 (5) | 10 ± 1 (5) | −46 ± 2 (5) | 5 ± 1 (5) |
| Ins1 endogenous | 5 mm glucose | −70 ± 3 (16) | 9 ± 1 (16) | −80 ± 4 (6) | 9 ± 1 (6) | −41 ± 3 (6) | 5 ± 1 (6) |
| Ins1 endogenous | 11 mm glucose | −74 ± 2 (13) | 9 ± 1 (13) | −73 ± 6 (9) | 9 ± 1 (9) | −43 ± 4 (9) | 5 ± 1 (9) |
| Ins1 endogenous | 25 mm glucose | −72 ± 4 (7) | 9 ± 1 (7) | −78 ± 2 (11) | 11 ± 1 (11) | −39 ± 2 (11) | 5 ± 2 (11) |
| NaV1.7 | Control | −99 ± 1 (5) | 7 ± 1 (5) | n/a | n/a | n/a | n/a |
| NaV1.7 | 50 μm PIP2 diC8 | −97 ± 2 (5) | 7 ± 1 (5) | n/a | n/a | n/a | n/a |
| NaV1.7 | Control | −98 ± 3 (7) | 11 ± 2 (7) | n/a | n/a | n/a | n/a |
| NaV1.7 | 50 μm neomycin | −98 ± 1 (7) | 8 ± 1 (7) | n/a | n/a | n/a | n/a |
V h and k value for the indicated NaV currents and treatment conditions. Values represent means ± SEM of indicated number of cells (n). Inactivation curves are presented in Fig. 12. V h represents membrane potential at which inactivation is half‐maximal in cells with monophasic inactivation and k represents the slope factor. In cells with biphasic inactivation, V h1 and V h2 represent the membrane potential at which inactivation is half‐maximal for the current components inactivating at negative and positive membrane potentials, respectively. k 1 and k 2 represent the respective slope factors for the currents inactivating with V h1 and V h2.