Table 1.
ECG parameters obtained from experiments with of isolated perfused guinea-pig hearts
| Heart rate (beats·min−1) | PR interval (ms) | QRS interval (ms) | RR interval (ms) | QT interval (ms) | QTc interval Fredericia (ms) | QTc interval Bazett (ms) | |
|---|---|---|---|---|---|---|---|
| Vehicle baseline | 209.0 ± 6.7 | 62.6 ± 1.0 | 18.6 ± 0.7 | 285.6 ± 10.1 | 157.9 ± 3.8 | 239.8 ± 3.2 | 295.6 ± 2.6 |
| Vehicle 45 min | 202.0 ± 6.4 | 64.5 ± 1.2 | 19.1 ± 0.9 | 299.9 ± 11.1 | 162.7 ± 4.2 | 243.1 ± 3.6 | 297.3 ± 3.3 |
| Dox 30 µM baseline | 210.9 ± 8.4 | 64.2 ± 1.8 | 21.3 ± 1.4 | 288.0 ± 11.5 | 166.2 ± 3.0 | 251.8 ± 2.4 | 310.1 ± 3.0 |
| Dox 30 µM 45 min | 183.9 ± 5.1** | 67.3 ± 1.6 | 22.0 ± 1.4 | 328.7 ± 9.1 | 195.3 ± 3.0** | 283.1 ± 2.9** | 340.9 ± 3.5** |
| Dex 30 µM baseline | 214.2 ± 7.4 | 65.7 ± 2.2 | 19.5 ± 0.4 | 281.8 ± 9.2 | 155.8 ± 5.4 | 237.6 ± 6.3 | 293.5 ± 7.0 |
| Dex 30 µM 45 min | 207.6 ± 6.9 | 66.3 ± 2.3 | 19.8 ± 0.6 | 290.0 ± 9.6 | 152.7 ± 5.4 | 230.6 ± 6.5** | 283.5 ± 7.4** |
| Dox 30 µM + Dex 3 µM baseline | 204.3 ± 9.2 | 64.0 ± 2.2 | 18.3 ± 0.8 | 301.5 ± 15.0 | 165.0 ± 4.1 | 246.3 ± 2.7 | 301.1 ± 3.0 |
| Dox 30 µM + Dex 3 µM 45 min | 178.3 ± 7.6 | 66.2 ± 2.5 | 18.8 ± 0.9 | 345.0 ± 13.8 | 182.5 ± 3.6† | 260.4 ± 2.7† | 311.1 ± 3.1† |
| Dox 30 µM + Dex 10 µM baseline | 198.1 ± 8.8 | 66.0 ± 1.3 | 22.3 ± 3.7 | 308.2 ± 13.7 | 171.0 ± 2.8 | 253.5 ± 2.5 | 308.7 ± 4.1 |
| Dox 30 µM + Dex 10 µM 45 min | 170.9 ± 2.9 | 68.5 ± 1.8 | 22.5 ± 3.6 | 353.3 ± 3.5 | 191.5 ± 2.6 | 270.9 ± 3.7† | 322.2 ± 4.5 |
| Dox 30 µM + Dex 30 µM baseline | 192.1 ± 9.3 | 67.0 ± 2.0 | 18.5 ± 0.8 | 316.8 ± 17.0 | 173.7 ± 4.0 | 255.1 ± 2.2 | 309.3 ± 2.9 |
| Dox 30 µM + Dex 30 µM 45 min | 174.7 ± 8.0 | 71.0 ± 1.3 | 19.0 ± 0.7 | 347.8 ± 15.0 | 187.0 ± 4.2†† | 266.0 ± 2.5†† | 317.5 ± 2.1†† |
| Mox 100 µM baseline | 204.3 ± 4.3 | 58.0 ± 1.8 | 18.3 ± 1.8 | 295.5 ± 6.7 | 169.5 ± 4.5 | 254.4 ± 5.0 | 311.7 ± 5.2 |
| Mox 100 µM 45 min | 168.0 ± 5.2** | 70.3 ± 3.1 | 20.3 ± 1.8 | 363.0 ± 12.7 | 220.8 ± 5.8** | 309.4 ± 5.1** | 366.4 ± 4.5** |
| Mox100 µM + Dex 30 µM baseline | 191.5 ± 8.3 | 63.5 ± 1.0 | 18.3 ± 0.9 | 301.0 ± 8.1 | 168.8 ± 4.1 | 251.8 ± 4.4 | 307.6 ± 4.7 |
| Mox 100 µM + Dex 30 µM 45 min | 158.3 ± 3.3 | 73.5 ± 2.5 | 20.0 ± 0.7 | 368.5 ± 7.1 | 218.0 ± 4.1 | 304.1 ± 4.4 | 359.1 ± 4.6 |
Values in the Table are means ± SEM from from 10 hearts in the vehicle group, from six hearts in the groups Dox 30 µM, Dex 30 µM, Dox 30 µM + DEX 3 µM, Dox 30 µM + Dex 10 µM and Dox 30 µM + Dex 30 µM, and from four hearts in the Mox 100 µM and Mox 100 µM + Dex 30 µM groups.
**
P < 0.01 different from the control group.
†
P < 0.05 different from Dox 30 µM group.
††
P < 0.01 different from Dox 30 µM group.
Dex, Dexrazoxane; Dox, Doxorubicin; Mox, Moxifloxacin.