Structural Alterations in Fibrin Clots with Dextran

Abstract

SummaryTheoretical reasoning underlying physicochemical measurement of opacity ratio of fibrin clots, i. e. the ratio of turbidity at 350 nm and 608 nm is given. From such considerations it is deduced that opacity ratio may be used to characterise clot morphology : opacity ratio will be inversely related to the size of inhomogeneities formed in the clot.A highly reproducible technique for the measurement of opacity ratio is described. Additions of small amounts of dextran to fibrinogen solution consistently decrease the opacity ratio of clots made subsequently. This decrease which indicates that the inhomogeneities forming in such fibrin clots are larger than control, is independent of the molecular weight of dextran, but is related to the logarithm of the final dextran concentration. Both thrombin and fibrinogen concentrations are also determinants of opacity ratio. Electron microscopy of fibrin clots made in the presence of dextran confirms that such clots have an altered morphology. Properties of clots in relationship to their structural morphology are discussed.