Table 1.
The mean data of standard AP parameters in a Langendorff-perfused rabbit heart.
| Pacing | AT | dV/dtmax | APA | APD20 | APD50 | APD90 | RP |
|---|---|---|---|---|---|---|---|
| (ms) | (V/s) | (mV) | (ms) | (ms) | (ms) | (mV) | |
| Atrial | |||||||
| Control | 143.2 ± 6.4 | 164.2 ± 7.9 | 105.9 ± 1.1 | 91.7 ± 4.9 | 133.6 ± 3.7 | 162.1 ± 2.6 | −81.0 ± 2.4 |
| CAR10 | 147.7 ± 6.7∗ | 182.6 ± 8.1∗ | 107.0 ± 1.2 | 87.8 ± 3.5 | 129.2 ± 2.9∗ | 158.0 ± 2.6∗ | −80.2 ± 0.9 |
| CAR30 | 154.9 ± 6.3∗ | 149.9 ± 13.0 | 105.6 ± 1.2 | 87.6 ± 3.5 | 126.0 ± 3.4∗ | 155.2 ± 3.3∗ | −79.4 ± 1.6 |
| CAR100 | 172.4 ± 2.6∗ | 129 ± 14.7∗ | 103.8 ± 1.1∗ | 84.0 ± 4.5∗ | 121.4 ± 4.7∗ | 152.2 ± 3.6∗ | −81.4 ± 1.9 |
| CAR300 | ~226.9 | ~109.5 | ~97.9 | ~46.9 | ~77.7 | ~122 | -78.4 |
| Endo- | |||||||
| Control | 27.9 ± 1.9 | 161.0 ± 6.9 | 106.1 ± 1.2 | 89.2 ± 4.1 | 132.6 ± 2.9 | 161.5 ± 1.9 | −82.8 ± 1.5 |
| CAR10 | 29.1 ± 2.2 | 164.8 ± 7.9 | 107.1 ± 1.2 | 86.5 ± 3.7 | 128.7 ± 2.8∗ | 157.8 ± 1.8∗ | −81.4 ± 0.9 |
| CAR30 | 29.5 ± 2.1∗ | 150.5 ± 7.9 | 105.0 ± 1.4 | 85.5 ± 3.5 | 126.5 ± 2.7∗ | 156.0 ± 2.7∗ | −80.4 ± 1.3 |
| CAR100 | 31.1 ± 1.6∗ | 121.9 ± 8.9∗ | 100.8 ± 2.6∗ | 81.2 ± 4.4∗ | 120 ± 3.8∗ | 152 ± 2.3∗ | −81.3 ± 1.3 |
| CAR300 | 41.3 ± 3.2∗ | 76.9 ± 7.5∗ | 98.0 ± 2.3∗ | 72.1 ± 5.4∗ | 112 ± 6.6∗ | 154.8 ± 6.9 | −78.6 ± 1.0 |
| Epi- | |||||||
| Control | 41.6 ± 2.1 | 172.7 ± 10.0 | 106.3 ± 1.2 | 89.3 ± 3.9 | 131.1 ± 2.0 | 160.6 ± 2.2 | −81.8 ± 2.4 |
| CAR10 | 42.5 ± 2.5 | 169.7 ± 8.5 | 107.0 ± 1.2 | 89.1 ± 3.9 | 129.6 ± 3.3 | 158.2 ± 3.2 | −80.5 ± 1.1 |
| CAR30 | 44.1 ± 3.1 | 155.4 ± 8.1 | 105.2 ± 1.0 | 87.8 ± 3.2 | 125.4 ± 3.1∗ | 154.4 ± 2.9∗ | −79.5 ± 1.6 |
| CAR100 | 45.2 ± 2.9∗ | 124 ± 12.7∗ | 103.9 ± 1.0∗ | 83.7 ± 4.6∗ | 121.9 ± 5.1∗ | 153.1 ± 3.8∗ | −80.7 ± 1.6 |
| CAR300 | 62.8 ± 3.7∗ | 66.8 ± 11.8∗ | 97.9 ± 2.8∗ | 72.0 ± 5.4∗ | 111 ± 7.4∗ | 156.1 ± 7.3 | −77.6 ± 0.8 |
Control: Tyrode solution containing blebbistatin (10 μM); CAR10-300: carvacrol effects with the maximal changes in APD at 10 μM, 30 μM, 100 μM, and 300 μM CAR concentrations, respectively; RP: resting membrane potential; APA: action potential (AP) amplitude; APD20, APD50, and APD90: AP duration at 20%, 50%, and 90% levels of repolarization, respectively; dV/dtmax: the maximal value of the first time derivative of the AP upstroke; AT: activation time. Statistical analysis was performed using ANOVA, ∗p < 0.05 for CAR vs. control, n = 5 for each during atrial and epicardial pacing, and n = 9 for each during endocardial pacing. Note that the data presented at 300 μM CAR under atrial pacing are from one successful measurement. The mean ± standard error of the mean was not determined because of the appearance of atrioventricular blocks. The average depth of microelectrode insertion was 1.82 ± 0.57 mm from the epicardium.