THE LYMPHATIC SYSTEM IN INFLAMMATION
1973; Elsevier BV; Linguagem: Inglês
10.1016/b978-0-12-783402-3.50013-5
Autores Tópico(s)Lymphatic System and Diseases
ResumoPublisher Summary This chapter discusses the lymphatic system in inflammation. The lymphatic system is very similar to the blood vascular system from the venous capillaries onward. There are innumerable small, thin-walled vessels that merge centrally into progressively larger ones. The peripheral vessels have been termed lymphatic capillaries, terminal lymphatics, small lymphatics, and peripheral lymphatics. The principal functions of the system are to remove particles, macromolecules, and excess fluid from the tissues and to transport them to the blood. Inflammation opens the lymphatic junctions because edema causes the filaments to dilate the vessels and to drag the cells apart. In extreme cases, this might damage the junctions during the compression phase of the initial lymphatic cycle. Injurious substances may also damage the tight junctions and cause endothelial contraction. Any breaks in the plasma membranes help to destroy the effectiveness of the pumping. The accumulation of fluid in the tissues reduces the outwardly directed hydrostatic pressure difference until edema appears, and the pressure difference is directed into the vessels. In moderate burns, there is about a threefold concentration of proteins inside the lymphatics, suggesting that here, osmotic pressure may still be an important force, but this is unlikely in the presence of the incompetent junctions and broken plasma membranes of very severe injuries.
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