Figure 2.
Effects of peptides on anti–Factor Xa activities in citrate and in plasma. The effect of peptides and protamine on neutralization of enoxaparin and unfractionated heparin was evaluated using the anti–Factor Xa assay kit in purified coagulation protein assays (ie, in sodium citrate) and in normal plasma. The X-axis indicates the concentration of peptide (μg/mL) relative to the volume of citrate or plasma used for the assay, and the Y-axis shows the amount of anti–Factor Xa activity neutralized (U/mL). (A) UFH in citrate. (B) UFH in plasma. (C) Enoxaparin in citrate. (D) Enoxaparin in plasma. Each point is the mean of triplicate analyses at each concentration from each of 3 healthy donors. Symbols represent peptides as follows: protamine, ; (ARKKAAKA)4, — · · —; C(ARKKAAKA)4C, – – – – – – –; (ARKKAAKA)3ARKKCAKA, - - - - - - - - - - -; (ARKKAAKA)3VLVLVLVL, ; (AKKARA)6, — · · · — · · ·; (ARKKAAKA)3(VL)3, — · — · —; and VLVL(ARKKAAKA)3ARKKCAKA, — — — — — —.