What is Anticoagulant
An anticoagulant is a substance that reduce blood clotting. This prevents deep vein thrombosis, pulmonary embolism, myocardial infarction and stroke.
substances in Anticoagulant
Coumadins : these anticoagulants act by causing a fall in level of these factors VII, IX and X and of prothrombin. Factor VII is the most affected. In Vitro, dicoumarol is quantitatively degraded to salicylic acid, and oral administrations of salicylates are known to give rise to hypoprothrombinaemia. Dicoumarol formation in the intestine from sulphonamides orally administrated has been suggested by some.
Heparin. Failure of blood coagulation in anaphylactic shock is due to the presence of excess of heparin in the blood. Heparin was first isolated from the liver, hence the name. it found in extracts of other organs. It maintains the natural fluidity of blood in the blood vessel, the normal concentration in blood being 0’009mg. per 100ml. Heparin is normally secreted by mast cells of connective tissue distributed throughout the body. These mast are characteristically found singly or in clumps, in close proximity to the walls of some blood vessels, or interposed in their lining endothelium. These cells contain numerous heparin granules. In conditions of shock, the heparin content of blood is increased 20 to 40 times the normal, and at the same time these mast cells show loss of their granules due to exhaustion. Heparin is though to be a dextrorotary polysaccharide made up of hexosamine and hexuronic acid units containing sulphuric acid ester groups. It prevents coagulation acting mainly as an antithrombin and an inhibitor of thromboplastin generation
Other Health Tips and Articles
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- What is Prothrombin Prothrombin is a glycoprotein in the liver with the help of vitamin K and present in the blood plasma in the normal concentration 15 to 20mg. per 100ml. of plasma. Normally there in a large excess of prothrombin in plasma over the amount required for effecting coagulation of blood. Therefore, a reduction of prothrombin to a large extent is required before a prolongation of the coagulation time is noticed. Prothrombin has a molecular weight of...
- DEFECTS IN PLATELETS Platelets are derived from megakaryocytes of bone marrow. These are oval and thin, non-nucleated discs 2 to 3 microns in diameter. Normal count – 250,000 – 500,000 per c.mm. of blood. Agglutination of platelets is favoured by substances exuded by injured tissue, and inhibited in vitro, by anticoagulants like citrate or oxalate, or in vivo, by heparin and dicoumarol. Their number is increased by the acute blood loss, trauma, partial asphyxia and splenectomy. The platelets...
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