Table 1.
Composition of solutions used for functional experiments.
| Standard | Na+-free | Na+-free | Na+ and K+-free | High K+ | |
|---|---|---|---|---|---|
| HEPES | HEPES | HEPES + NH4CI | HEPES | calibration | |
| NaCl | 125 | - | - | - | - |
| NMDG | – | 125 | 105 | 130 | 32.8 |
| NH4CI | – | – | 20 | – | – |
| KC1 | 3 | 3 | 3 | 3 | 105 |
| MgS04 | 1.2 | 1.2 | 1.2 | 1.2 | 1.2 |
| CaCl2 | 1 | 1 | 1 | 1 | 1 |
| KH2P04 | 2 | 2 | 2 | 2 | – |
| Glucose | 5 | 5 | 5 | 5 | – |
| HEPES | 32.2 | 32.2 | 32.2 | 32.2 | 32.2 |
| pH | 7.4 | 7.4 | 7.4 | 7.4 | 6.0, 7.0, 8.0 |
NMDG is N-Methyl-D-Glucamine, all solutions were titrated to pH 7.4 at 37 °C using either NaOH or KOH. NMDG was titrated with HCl.