B Blood and Bloodforming Organs

BOIA A Vitamin K antagonist This group comprises vitamin K antagonists such as the dicoumarol group. The plant Melilotus officinalis (L.) Pallas, family Fabaceae, that has become mouldy due to microorganisms, caused disease in grazing cows, Sweet Clover Disease , where the cows died ftom internal bleeding. The discovery that this disease was 

Coumarins are nowadays produced synthetically. The story of dicoumarol shows again the usefulness of natural drugs as models for new drugs. 

Heparin inhibits blood coagulation both in vivo and in vitro. In combination with a co-factor, antithrombin III, heparin interferes with several steps in the coagulation process. Furthermore, heparin activates lipoprotein-lipase, which splits triglycerides into free fatty acids and glycerol. 

Heparin is administered intravenously or subcutaneously. The maximal anticoagulant effect is obtained within a few minutes after intravenous injection, 2-3 hours after slow intravenous infusion and within 2—4 hours after subcutaneous injection. The indications are the prophylaxis and treatment of thromboses and embolism of the lungs. 

BOIA D Enzymes Streptokinase For medical purposes a highly purified streptokinase preparation is used. It is produced by cultivation of a Jl-haemolytic Streptococcusstmn., belonging to Lancefield group C. After several purification steps the culture solution is purified by removal of various other enzymes such as streptodornase, streptolysin and hy-aluronidase. 

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