TABLE IV.
Composition of Flux Solutions
| Solution (in mM) | Na+ | Rb+ or K+ | Cl− | Ca2+ | Mg2+ | PO4 2− | SO4 2− | HEP | GLU | SUC | OSM |
|---|---|---|---|---|---|---|---|---|---|---|---|
| A. Regular medium (R) | 87 | 5 | 86 | 2 | 2 | 1 | 1 | 10 | 0 | 0 | 200 |
| B. Modified R (RΔ) for 22Na+ influxes | 43 | 5 | 86 | 2 | 2 | 1 | 1 | 10 | 0 | 0 | 200 |
| B. Hyperosmolar (R-SUC) | 87 | 5 | 86 | 2 | 2 | 1 | 1 | 10 | 0 | 84 | 284 |
| C. Wash | 19 | 73 | 8 | 2 | 2 | 1 | 1 | 10 | 78 | 0 | 200 |
| D. Barth's medium | 90.4 | 1 | 90 | 0.7 | 0.8 | 0 | 0.8 | 10 | 0 | 0 | 200 |
In medium RΔ, NaCl was replaced by an equimolar concentration of NMG-Cl. Barth's medium contains, in addition, 0.7 mM NO3 2− and 2.4 mM HCO3 −. All solutions are at pH 7.4. Here, R = regular, GLUC = gluconate, HEP = HEPES, SUC = sucrose, and OSM = osmolality.