TABLE 4.
Drug selectivity for milrinone (M), amrinone (A), and levosimendan (L) at temperatures ranging from 37°C to 20°C. Values are ratios between IC50-values for different elimination ways of cAMP and cGMP. Neither of the drugs inhibited ABCC4-activity below 28°C.
| Drug selectivity (IC50)/(IC50) | (PDE5)/(PDE3) inhibition | (cGMP-efflux)/(cAMP-efflux) inhibition | (cAMP-efflux)/(PDE3) inhibition | (cGMP-efflux)/(PDE5) inhibition | ||||||||
| Temperature | M | A | L | M | A | L | M | A | L | M | A | L |
| 37°C | 112 | 10.38 | 472 | 0.39 | 0.47 | 3.03 | 19.66 | 0.441 | 28.76 | 0.068 | 0.020 | 0.184 |
| 34°C | 144 | 9.32 | 510 | 0.27 | 2.01 | 1.09 | 37.86 | 0.123 | 43.45 | 0.070 | 0.026 | 0.093 |
| 32°C | 215 | 5.61 | 846 | 0.52 | 0.32 | 0.80 | 25.27 | 0.364 | 85.98 | 0.061 | 0.021 | 0.081 |
| 28°C | 370 | 6.06 | 1820 | 0.49 | 0.13 | 0.44 | 45.40 | 0.537 | 270.7 | 0.060 | 0.012 | 0.065 |
| 24°C | 133 | 3.98 | 427 | - | - | - | - | - | - | 0.034 | 0.011 | 0.124 |
| 20°C | 154 | 3.98 | 450 | - | - | - | - | - | - | 0.022 | 0.052 | 0.045 |