From Big Medical Encyclopedia

EXUDATION (exsudatio; lat. exsudare to come to light, to be allocated) — process of movement of exudate (the liquid rich with protein and the blood containing uniform elements) of small veins and capillaries in surrounding fabrics and cavities of an organism; it is observed at an inflammation.

An important role in this process is played reaction of a microcirculator bed with disturbance of a blood-groove and rheological properties of blood, increase in permeability of vessels with transuding of plasma, emigration of uniform elements of blood and phagocytosis. Changes in a microcirculator bed begin with a reflex spasm of arterioles and precapillaries, to-ry quickly is replaced by a peristatic hyperemia from a rassha rhenium of arterial and venulyarny departments of vascular network. Delay of a blood-groove — prestaz, passing in staz (see), expressed as in post-capillary and venulyarny departments of a microcirculator bed, and in limf is a consequence of it. vessels. At a long staz there is an aggregation of uniform elements of blood to thrombosis of post-capillaries and venules or hemorrhage in the absence of thrombosis. Besides, change of rheological properties of blood promotes redistribution of polymorphonuclear leukocytes, to-rye at a slow blood flow are located in the fringe region along a vascular wall. The increased vascular permeability (see) E is shown. plasmas, emigration of uniform elements of blood also develops after damage and a hyperemia under the influence of chemical mediators. Most accurately this process comes to light in endotheliocytes, in cytoplasm to-rykh at an elektronnomikroskopichesky research find swelling of mitochondrions, formation of polyribosomes and a large number of mikropinotsitozny vesicles.

Depending on weight of damage of a vascular wall and intensity of action of mediators the nature of transuding of plasma can be various. So, at small damage low-molecular albumine filters, and at more expressed — large molecules of albumine and fibrinogen. Depending on it there can be various also a character of exudate. Along with the above described processes through a wall of vessels there is an emigration of uniform elements of blood (see the Inflammation, an etiology and pathogenetic mechanisms).

See also Exudate .

Bibliography: See bibliogr. to St. Exudate.

G. M. Mogilevsky