Oncotic pressure

The colloid osmotic pressure ( COP ) (also oncotic pressure ) is the proportion of the osmotic pressure, which is caused by the colloids of a solution.

In human body fluids, such as blood plasma, the colloid osmotic pressure is determined mainly by proteins, such as albumin or globulins, determined. It is essential for the maintenance of plasma volume, as in humans, the vessel wall is usually well permeable to small molecular weight plasma components (eg ions), so that the osmotic pressure difference would almost always be balanced. Since the endothelium but is different permeable colloids, creates a pressure in the vessel to the plasma into ( intravascular ) which counteracts the natural hydrostatic pressure by extravascular. The difference between these pressures (hydrostatic pressure - colloid osmotic pressure) is called the effective filtration pressure.

References and Literature

• Robert F. Schmidt, Florian Lang: Human Physiology. 30th edition Springer Medizin Verlag Heidelberg, ISBN 978-3-540-32908-4. P. 49 " oncotic pressure "

• Hematology
• Osmosis