Table 1.
Composition of experimental solutions
| Relaxing | Pre-activating | Activating | cATP | cATP + regen | EDTA rigor | 0 Mg2+ rigor | |
|---|---|---|---|---|---|---|---|
| MgAc | 7 | 7 | 7 | 7 | 7 | — | — |
| ATP | 5 | 5 | 5 | — | — | — | — |
| Caged ATP | — | — | — | 5 | 5 | — | — |
| KAc | 44 | 74 | 44 | 74 | 44 | 115 | 145 |
| Imidazole-Ac | 50 | 50 | 50 | 50 | 50 | 50 | 50 |
| EGTA | 10 | 0.1 | — | — | — | — | — |
| CaEGTA | — | — | 10 | 10 | 10 | — | — |
| Glutathione | 10 | 10 | 10 | 10 | 10 | — | — |
| EDTA | — | — | — | — | — | 10 | — |
| Phosphocreatine | 10 | 10 | 10 | — | 10 | — | — |
| CK (mg ml−1) | 2 | 2 | 2 | — | 2 | — | — |
| Apyrase (μg ml−1) | — | — | — | — | 7 | — | — |
Abbreviations: cATP, caged ATP; regen, phosphocreatine/creatine kinase regenerating system; Ac, acetate; CR-kin, creatine kinase. Concentrations are millimolar, except for CR-kin (mg ml−1) and apyrase (μg ml−1).