Argatroban Inhibition of Thrombin Bound to Aged Plasma Clots
| Clot Age (h) . | Platelet Count (108 cells/mL) . | Maximum Activity (mOD/min) . | IC50 (μmol/L) . | Maximum Inhibition (% Control) . | No. of Donors . |
|---|---|---|---|---|---|
| A. PRP | |||||
| 3 | 2.2 ± 0.6 | 12.5 ± 3.3 | 2.7 ± 1.0 | 83 ± 4 | 9 |
| 6 | 2.4 ± 0.4 | 13.1 ± 2.7 | 3.4 ± 3.1 | 80 ± 14 | 7 |
| B. PPP | |||||
| 3 | — | 12.0 ± 3.2 | 6.1 ± 3.0 | 88 ± 5 | 9 |
| 6 | — | 11.5 ± 3.4 | 2.9 ± 1.3 | 81 ± 12 | 7 |
| Average | — | 12.3 ± 3.1 | 3.8 ± 2.6 | 83 ± 9 |
| Clot Age (h) . | Platelet Count (108 cells/mL) . | Maximum Activity (mOD/min) . | IC50 (μmol/L) . | Maximum Inhibition (% Control) . | No. of Donors . |
|---|---|---|---|---|---|
| A. PRP | |||||
| 3 | 2.2 ± 0.6 | 12.5 ± 3.3 | 2.7 ± 1.0 | 83 ± 4 | 9 |
| 6 | 2.4 ± 0.4 | 13.1 ± 2.7 | 3.4 ± 3.1 | 80 ± 14 | 7 |
| B. PPP | |||||
| 3 | — | 12.0 ± 3.2 | 6.1 ± 3.0 | 88 ± 5 | 9 |
| 6 | — | 11.5 ± 3.4 | 2.9 ± 1.3 | 81 ± 12 | 7 |
| Average | — | 12.3 ± 3.1 | 3.8 ± 2.6 | 83 ± 9 |
Thrombin activity bound to aged plasma clots was determined by the clot permeation assay, as described in the text and legend to Fig 5. The average (±SD) of parameters, obtained with a series of individual donors from whose blood both PRP and PPP clots were prepared and analyzed, is shown. The maximum activity represents the mean and standard deviation of triplicate analyses in the absence of argatroban. The IC50 and maximum inhibition parameters (and their standard deviations) were obtained by nonlinear regression analysis of activity data, obtained as a function of argatroban concentration, using equation 2.