In essence, oncotic pressure (it is also osmotic) is compounds that dissolve in the blood cells and its plasma. With a lack of proteins in the body, it decreases, which can lead to the fact that due to the accumulation of fluid, edema will begin to appear. This is due to the fact that the membranes of the vessel walls are translucent and semipermeable. They pass water well and freely, while ions and molecules of various substances are worse.
Normal oncotic pressure is almost 7.5 atm. (5700 mmHg or 762 kPa). Plasma activity varies around 290 mosm/L.
However, osmotic pressure is measured not by the number of dissolved molecules, but by their concentration. Most of the plasma ions (about 99.5%) are inorganic ions, the concentration of which determines the oncotic pressure. The pressure of plasma proteins is only a small part, only 0.03-0.04 atm. (25-30 mmHg). Butit is worth remembering that the pressure exerted by proteins plays a critical role in the distribution of water between the plasma and underlying tissues.
This part of the procedure is considered to be the detection of oncotic pressure. Its participation in the distribution of water is indicated by the fact that the walls of the capillaries are basically impassable for proteins. There are much fewer proteins in the tissue fluid, so there is a gradient of their concentration on both sides of the capillary.
Due to the high oncotic pressure, fluid in the intercellular space does not accumulate, but circulates.
For the prevention of oncotic pressure, it is recommended to carry out preeclampsia therapy, which is quite wide-profile, so the result will not be long in coming. With a normal content of proteins in the blood, its coagulability is normalized, which reduces the risk of heart disease.
Oncotic blood pressure is usually kept at a constant level. Excretory organs, such as sweat glands and kidneys, take part in its neurohumoral regulation. A decrease or increase in oncotic pressure is perceived both on the periphery of the vessel walls and in the central part (hypothalamus), where the antidiuretic hormone is released, which affects the process of absorption into the renal canals. Also, its function is to regulate the process of urination. The stability of osmotic pressure is provided by ADN, aldosterone, parahormone, urenic hormone of the heart.
A reflex occurs in the excretory organs, a change in activity,leading either to excessive retention, or to a sharp loss of fluid and s alt in the body. In these processes, the first and leading role goes to proteins (oncotic pressure), which are able to bind and release ions. Thanks to the activity of excretory organs (kidneys and sweat glands), metabolic products that are constantly formed in the body, for the most part, do not have a negative effect on osmotic pressure.
Disturbances in the level of oncotic pressure are associated with an imbalance of total plasma protein, albumin and globulins, anions, cations, sodium, potassium, calcium and other components. This can be caused by various pathological conditions and diseases (intoxication, burns, postoperative period, shock, bleeding, various diseases, etc.). In such cases, it is extremely important to regularly check the oncotic pressure. Treatment is primarily aimed at eliminating the underlying disease and restoring the balance of s alts in the blood plasma. However, before treating pressure, especially oncotic, be sure to consult your doctor. Do not self-medicate!
