Muco:polysaccharide fractions derived from heparin - with selective inhibitory action against factor Xa but low anticoagulant activity

摘要

New muco-polysaccharide fractions (I) of high anti-Xa (Yin-Wessler) activity but low anticoagulant activity are prepd. by first suspending in an aq. medium an anticoagulant heparin material contg. both insoluble and soluble components. Some at least of the soluble components have different solubility coeffts. in a water-organic solvent mixt, permitting their sepn. from such a mixt. The resident suspended components are sepd. and the soln. treated with an organic solvent to cause sepn. of one fraction this is generally indicated by development of turbidity. The material responsible for this turbidity is recovered and further addn. of solvent made to the residual solns. esp. until addn. of more solvent no longer causes turbidity. (I) can be used to control particular stages in the blood coagulation process, esp. they have a powerful and specific inhibitory action against factor Xa so can be used in antithrombotic therapy without risk of causing haemmorhage. The toxicity of (I) is so low that the LD50 could not be measured at doses of 3.2g per. kg. in mice.