Figure 3.

Heparin stimulates antithrombin (AT) activity in the presence of hyaluronic acid (HA). Heparin (10 μg/ml) and various concentrations of HA were incubated with 150 μg/ml antithrombin in presence of 5 mmol/l CaCl₂. Thrombin activity of blank (reaction buffer only) was considered as 1 and the activities of other tests were normalized based on comparisons with blank. Values are expressed as mean ± standard deviation of data from triplicate experiments.