Under normal conditions, the blood is in a liquid state, which ensures its movement through the circulatory system. In infectious and invasive diseases, as well as intoxication, its physicochemical properties change, which negatively affects metabolic processes and the functioning of internal organs. In this case, the coagulation rate is of great biological importance. It can be accelerated and slowed down. In medicine, many pharmacological preparations are used with the help of which you can adjust the rate of blood coagulation. Anticoagulants are drugs that slow down the blood coagulation process , and agents that accelerate this protective reaction are called coagulants.
The mechanism of coagulation and the formation of blood clots is a complex biochemical process that protects the body from blood loss in violation of the integrity of blood vessels. This process is carried out due to prothrombin, which is synthesized in the liver, and platelets that adhere to the collagen fibers of the edges of the damaged vessel. In the process of platelet hydrolysis, macroergic compounds (adenosine triphosphate and adenosine diphosphate acids), thromboplastin and vasoconstrictor substances - norepinephrine, adrenaline, serotonin are released. They narrow the lumen of the vessel. Thromboplastin, under the influence of calcium and plasma proteins, combines with prothrombin and forms thrombin, which with the protein (fibrinogen) turns into insoluble fibrin, clogging the vascular lumen.
Blood coagulability slows down in diseases associated with a decrease in blood calcium, a decrease in platelet concentration, impaired synthesis of prothrombin, fibrinogen, and insufficient activity of thrombokinase and vitamin K. Thrombin, fibrinogen, calcium chloride, vicasol, aminocaproic acid, and vegetable are used as coagulants in medicine. preparations (nettle leaves, water pepper).
Anticoagulants - drugs that inhibit the activity of the biological system, which provides blood coagulation and prevents the formation of blood clots in blood vessels. They inhibit all or some phases of blood coagulation. It is known that the liquid state of the blood is supported by specific enzymes and antitrobmin. In order to prevent the formation of blood clots, direct-acting anticoagulants are used. They affect blood coagulation factors, delay this process in the body or test tube. Sodium citrate (sodium citrate) and EDTA (ethylenediaminetetraacetic acid) bind ionized blood calcium and are converted into calcium citrate or in complex with EDTA. Due to the removal of calcium ions from the blood coagulation system, thrombin and fibrin are not formed. Heparin inactivates thrombogenic factors and delays the conversion of prothrombin to thrombin. Anticoagulants - direct-acting drugs are prescribed for blood transfusions and laboratory hematological studies to prevent blood coagulation, as well as for the treatment of diseases that are accompanied by accelerated blood coagulation. These drugs are used for the prevention and treatment of thromboembolic complications.
Indirect anticoagulants - dicumarin, coumarin, syncumar - block the synthesis of enzymes that are involved in blood coagulation. They inhibit the formation of thrombin in the liver. This process develops in the body within 12â72 hours and manifests itself in a period of two to ten days. These are long-acting drugs. Anticoagulants - drugs of indirect action are prescribed for the prevention and treatment of thrombosis, embolism, thrombophlebitis.