Table 1.
The experimental protocol applied in isolated, Langendorff-perfused, AV-blocked rabbit hearts
| Group | n | Pretreatment (20 min) | Treatment (30 min) |
|---|---|---|---|
| First set of experiments | |||
| H2O | 8 | H2O | H2O |
| DMSO | 8 | DMSO | DMSO |
| Dofetilide 100 nmol·L−1 | 8 | DMSO | DMSO + dofetilide |
| SEA0400 1.0 µmol·L−1+ dofetilide 100 nmol·L−1 | 8 | DMSO + SEA0400 | DMSO + SEA0400 + dofetilide |
| Second set of experiments | |||
| Dofetilide 100 nmol·L−1 | 8 | DMSO | DMSO + dofetilide |
| Lidocaine 30 µmol·L−1+ dofetilide 100 nmol·L−1 | 8 | DMSO + lidocaine | DMSO + lidocaine + dofetilide |
| Verapamil 750 nmol·L−1+ dofetilide 100 nmol·L−1 | 8 | DMSO + verapamil | DMSO + verapamil + dofetilide |
The groups of hearts, the periods of the experiments and the applied drugs are summarized. In the baseline period of the experiments, all hearts were perfused with Krebs buffer; the perfusion solution was then switched to the test drug in the second period of the experiment (pretreatment); in the last period dofetilide was added to the perfusion (treatment). Group size is indicated by n.
AV, atrioventricular; DMSO, dimethyl sulphoxide.