The effects of some plasma proteins on fibrin network structure

Pronounced differences are found between characteristics of networks developed in plasma and those developed in pure fibrinogen solution. Networks in plasma have thicker fibres, are more permeable and have lower tensile strength. In this investigation the role of some plasma proteins as determinants of network structure under physiological conditions of clotting has been examined in an attempt to account for the differences in network structure in plasma and fibrinogen solution. The effect of physiological concentrations of antithrombin III, fibronectin, albumin, alpha globulin and gamma globulin on fibrin network structure was examined using mass-length ratio (muT) from turbidity, bulk network permeability (tau) and kinetics of network development. It was found that differences in fibrin network structure developed in plasma and pure fibrinogen solution could not be accounted for by alterations induced in network properties by albumin, gamma globulin, alpha globulin, fibronectin and antithrombin III. It is concluded that the final network structure is determined by the kinetics of fibrin fibre growth and is highly responsive to the presence of plasma proteins.