A novel functional assay for protein C in human plasma and its comparison with amidolytic and anticoagulant assay

GUGLIELMONE HUGO A; VIDES MIGUEL A

SCHATTAUER GMBH-VERLAG MEDIZIN NATURWISSENSCHAFTEN

Año: 1992 vol. 67 p. 47 - 47

simple and fast method for the quantitative determination of protein C activity in plasma is here described. The first step consists in the conversion of protein C in the test sample into activated protein C by means of an activator isolated from Southern Copperhead venom. Subsequently, the degradation of factor Va, in presence of protein C-deficient plasma, is measured by the prolongation of the prothrombin time which is proportional to the amount of protein C in the sample. The dose-response curve showed a linear relationship from 6 to 150% protein C activity and the inter- and intra-assay reproducibility was 3.5% and 5.6% respectively. In normal subjects, a mean of protein C level of 98 +/- 15% of normal pooled plasma was found. Comparison with the anticoagulant assay in samples of patients with oral anticoagulant, liver cirrhosis, disseminated intravascular coagulation and severe preeclampsia revealed an excellent correlation (r = 0.94, p less than 0.0