Table 1.
Ionic composition of solutions (mM)
| NaCl | KCl | CsCl | HEPES | CaCl2 | CdCl2 | Glucose | MgCl2 | |
|---|---|---|---|---|---|---|---|---|
| Bathing solutions (pH 7.4) | ||||||||
| Na+ currents | 140.0 | — | 5.4 | 5.0 | 1.8 | 0.5 | 10.0 | 0.5 |
| Ca2+ currents | 140.0 | 5.0 | 10.0 | 20.0a | — | 5.0 | — | |
| K+ currents | 140.0 | 5.0 | — | 10.0 | 2.0 | — | 10.0 | — |
| Maxi-BKca | — | 150.0 | — | 5.0 | 0.001 | — | — | — |
| Pipette solutions (pH 7.2) | ||||||||
| Na+ currents | 10.0 | — | 130.0 | 5.0 | — | — | ||
| Ca2+ currents | 10.0 | — | 130.0 | 10.0 | — | — | ||
| K+ currents | 10.0 | 130.0 | — | 10.0 | — | — | ||
| Maxi-BKca | — | 150.0 | — | 5.0 | — | — | — | 1.0 |
a
To measure Ca2+ currents, we substituted BaCl2 for CaCl2 equimolarly.