TY - JOUR

T1 - A computer assisted method to obtain the prothrombin activation velocity in whole plasma independent of Thrombin decay processes

AU - Hemker, H.C.

AU - Willems, G.M.

AU - Beguin, S.

PY - 1986

Y1 - 1986

N2 - A method is described that, on the basis of the time course of amidolytic activity after the triggering of thrombin generation in normal plasma, allows the calculation of the velocity of prothrombin conversion independent of thrombin inactivating processes. It is shown how the reaction constants for the α2M-dependent and the α2M-independent thrombin inactivation processes can be obtained in a sample of whole plasma. The method is verified by demonstrating that the experimentally observed time courses of residual prothrombin and of α2M-thrombin complex coincide with those calculated from the time course of amidolytic activity, and by showing that the course of prothrombin conversion in plasma without α2-macroglobulin or AT III is adequately described if the α2M or AT Ill-dependent breakdown constants are taken zero in the calculations. It appears that the inactivation of thrombin, endogenously generated in whole plasma, is about half as fast as that of exogenous thrombin added to the plasma. A computer program is presented that carries out the relevant calculations.

AB - A method is described that, on the basis of the time course of amidolytic activity after the triggering of thrombin generation in normal plasma, allows the calculation of the velocity of prothrombin conversion independent of thrombin inactivating processes. It is shown how the reaction constants for the α2M-dependent and the α2M-independent thrombin inactivation processes can be obtained in a sample of whole plasma. The method is verified by demonstrating that the experimentally observed time courses of residual prothrombin and of α2M-thrombin complex coincide with those calculated from the time course of amidolytic activity, and by showing that the course of prothrombin conversion in plasma without α2-macroglobulin or AT III is adequately described if the α2M or AT Ill-dependent breakdown constants are taken zero in the calculations. It appears that the inactivation of thrombin, endogenously generated in whole plasma, is about half as fast as that of exogenous thrombin added to the plasma. A computer program is presented that carries out the relevant calculations.

U2 - 10.1055/s-0038-1661594

DO - 10.1055/s-0038-1661594

M3 - Article

SN - 0340-6245

VL - 56

SP - 9

EP - 17

JO - Thrombosis and Haemostasis

JF - Thrombosis and Haemostasis

IS - 1

ER -