Postkapilläre

Postkapilläre refers to the vascular compartment that exists between the capillaries and the general circulation of blood. It is a critical component of the body's fluid dynamics and is involved in the exchange of substances between the blood and the interstitial fluid.

The postcapillary venous system, which includes the venules and collecting venules, is a high-traffic area with a large number of blood cells passing through. The blood is slowed down in these vessels, allowing for efficient exchange of substances with the surrounding interstitial fluid. The postcapilläre compartment is characterized by a low oncotic pressure and a high hydrostatic pressure, which facilitates the movement of fluid from the capillaries into the interstitial space.

In the context of inflammation, the postcapilläre compartment plays a key role in the recruitment of leukocytes. Leukocytes adhere to the walls of the venules and are then transmigrated into the interstitial tissue, where they participate in the inflammatory response. The postcapilläre compartment also serves as a site for the accumulation of immune cells, such as macrophages and T-cells, during certain types of immune responses.

Disorders of the postcapilläre compartment, such as capillaritis and postcapillary venous hypertension, can lead to tissue damage and organ dysfunction. Understanding the normal physiology of the postcapilläre compartment is essential for the diagnosis and treatment of various diseases that affect this region of the body.