The anticoagulant effect of chondroitin-4-sulfate

Chondroitin-4-sulfate (chondroitin sulfate A, CSA) is a natural glycosaminoglycan which has been shown to have antithrombotic effects in vivo. This study investigates its anticoagulant effect in vitro. CSA was added to citrated plasma obtained from 16 human volunteers to yield concentrations ranging from 25 to 500 micrograms/ml. The anticoagulant effect of CSA was determined by activated partial thromboplastin time (APTT). The average baseline APTT was 32.5 +/- 3.4 sec. An excellent linear relationship was observed between the natural logarithms of APTT and plasma CSA concentrations; the slopes of these relationships (APTT-CSA slopes) were determined by linear regression. The average APTT-CSA slope was 0.986 +/- 0.145 ml/mg. Plasma concentrations of antithrombin III, alpha 1 antitrypsin, alpha 2 macroglobulin, fibrinogen, and alpha 1 acid glycoprotein were normal. There were no statistically significant correlations between baseline APTT and APTT-CSA slope values or between either of these parameters and plasma concentrations of any of the measured plasma proteins. Additional in vitro studies showed that the anticoagulant effect of CSA is only in part mediated by antithrombin III. The results of this study suggest that the antithrombotic effect of this biologically active substance are at least in part due to its anticoagulant effect.