Mesothelium [Mesothelium, Lnh; Meso- + (Epi)Tely]

Mesothelium is a layer of flat cells lining the surfaces of the peritoneum, pleura, pericardium and serous membranes of other organs. Mesothelial cells form a single-layer squamous epithelium that covers the inner surface of cavities and the outer surface of organs. The main functions of the mesothelium are to reduce friction between organs due to the production of a lubricating fluid, prevent the adhesion of layers of serous membranes, participate in the resorption of transudate and the absorption of substances from cavities. Damage to the mesothelium can lead to the development of inflammatory diseases and cancer processes.

Mesothelium is a layer of flat cells about 0.02 mm thick that cover the inner surface of the abdominal, thoracic, pleural and pericardial cavities, as well as the serous membranes of other organs. Between the mesothelial cells there is a serous fluid that acts as intercellular lubrication and hydroprotection in the body.

The main function of the mesothelium is to maintain a constant internal environment in the organ. When fluid from the surface of the fetus and mesothelial cells come into contact, its surface layer shrinks, which prevents the flow of fluid between the external and internal contents of the placenta and fetus. The same thing happens when the liquid contents of the cavity come into contact with air. To protect against evaporation of serous fluid in mammals (including humans), hypoxia during childbirth reduces the pressure of the aqueous fluid on the outer surface of the membranes. This results in slight adhesion of the membrane's fluids to the contents inside, allowing normal pressure inside to be maintained after birth. However, with frequent deliveries (caesarean section or vacuum contraction of the uterus), collapse of the mesothelial membrane (atelectasis) may occur, which often leads to complete blockage of blood vessels and a subsequent decrease in abdominal volume due to a decrease in the amount of retained serosa