Fibrinogen/fibrin

Interaction ofLp(a) in the Process of Activation of Plasminogen to Plasmin by Tissue-Type Plasminogen Activator on Fibrin, Fibrinogen, and Fibrin(ogen) Fragments... 

Note In fibrinolysis, plasmin, an endopeptidase that is converted from plasminogen by an activator, hydrolyzes fibrin, fibrinogen, factor V, and factor VIII to their inactive products. Hageman factor (factor XII) converts a proactivator to the active activator. Agents such as thrombin, streptokinase, and urokinase therefore enhance the formation of plasmin and hence have fibrin lytic properties. Epsilon-aminocaproic acid inhibits the activator-mediated formation of plasmin and hence may be used as an antidote to streptokinase-urokinase, or in a defibrination syndrome when bleeding from a mucous membrane occurs. 

The presence of markers of thrombin generation, thrombin activity, and fibrin (fibrinogen) degradation indicates that... 

Perlecan, decorin, aggrecan, laminin, gelatins, collagens III, IV, V, VII, IX, X, XI, fibrin, fibrinogen, fibronectin, proMMP-9, proMMP-1... 

When blood coagulates, the soluble fibrinogen converts into insoluble fibrin. Fibrinogen has a molar mass of about 330 000 g/mol. It consists of a double helix 1.5 nm in diameter with a 6-nm-diameter, globulinlike section at both ends and one of 5 nm in diameter in the center. Through the action of thrombin, two so-called B-peptides with Af = 2 460 g/mol are eliminated from the central part and two A peptides having M = 1 890 g/mol from one of the ends. In a sequence of reactions that remains to be fully explained, this activated fibrinogen is then converted into fibrin. 

Lorand [18] believes that the terminal glycine of the fibrin is involved in the formation of peptide bonds with other fibrin molecules. This process is catalyzed by a fibrin-stabilizing factor (FSF), factor XIII, which has the catalytic properties of a transamidase and is calcium dependent. In the presence of fibrinogen or fibrin, FSF catalyzes the formation of a fibrin-fibrinogen complex soluble at a physiological pH. Thus fibrinogen inhibits the irreversible polymerization of fibrin. 

The model describes the formation of the main regulators of fibrin polymerization in the blood - activator of clotting (thrombin), the concentration of which is noted by 6, the inhibitor concentration is indicated by cj). Thrombin catalyzes a reaction to convert the precursor of fibrin - fibrinogen into fibrin monomer, concentration of which is denoted by 0, it in turn pol3rmerizes in case and gives thrombus. 

Stathakis NE, Mosesson MW, Chen AB, Galanakis DK 1978. Cryoprecipitation of fibrin-fibrinogen complexes induced by the cold-insoluble globulin of plasma. Blood 51(6) 1211-1222. 

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