fibrin-, fibrino-

An abnormal type of fibrinogen (protein present in blood plasma; converts to fibrin when blood clots) very rarely found in human plasma; it is precipitated upon cooling, but redissolves when warmed to room temperature.

1. The protein formed during normal blood clotting which is the essence of the clot.
2. An insoluble protein that is essential to the clotting of blood, formed from fibrinogen with the action of thrombin (key blood clot promoter).

The substance is produced in threads; after the threads have formed a close meshwork through the blood, they contract, and produce a dense, felted mass.

Fibrin is found in all inflammatory conditions within serous cavities like the pleura, peritoneum, and pericardium, and forms a thick coat upon the surface of the inflamed joints, and in the lung as a result of pneumonia.

Having the appearance of fibers; fiber-like.

1. A protein synthesized by the liver and present in blood plasma that is converted into fibrin through the action of thrombin (an enzyme that acts on fibrinogen in blood causing it to clot) and in the presence of calcium ions.
2. A soluble protein present in the blood that is activated by thrombin to form fibrin.

Fibrinogen is a clotting factor and is required to prevent major blood loss.

The formation or production of fibrin.

1. A concentration of fibrinogen in the blood that is less than what is considered to be normal.
2. The reduction or decrease in the amount of fibrinogen in the blood, usually because of a liver disorder.

1. Resembling fibrin.
2. A homogenous acellular material similar to fibrin, found normally in the placenta and formed in connective tissue and in the walls of blood vessels in certain disease conditions.

1. A normal ongoing process that dissolves fibrin and results in the removal of small blood clots.
2. The dissolution of fibrin by enzymatic action.
3. A complicated system of biochemical reactions for lysis (dissolution or destruction of cells such as blood cells) of clots in the vascular system.

The insoluble protein fibrin is broken down by the enzyme plasmin which is activated at the same time as the coagulation process of blood.

There is normally a balance between coagulation and fibrinolysis; an abnormal increase in the latter causes excessive bleeding.