Composition and Functioning of the Extracellular Matrix

Extracellular matrix (intercellular, pericellular matrix) is composed of a variety of polysaccharides and proteins that are spontaneously organized into ordered structures. It represents a supramolecular complex, formed by a network of molecules connected to each other [31,41]. In the human body, the extracellular matrix produces highly speciaUzed structures such as cartilage of the tendon, the basal membrane and after the secondary deposition of calcium phosphate, bones and teeth. Since these structures differ both in molecular composition and methods for organizing the main components, they comprise the various forms of the extracellular matrix [31,41]. Here we draw a generalized picture of the extracellular matrix and the functional role of hyaluronan in it. 

The extracellular matrix is an area of biopolymer self-assembly and these are exported to the extracellular space by fibroblasts or the cells of this family (chondroblasts in cartilage and osteoblasts in bone tissue). The molecular structure of the extracellular matrix is 

A constant exchange of liquid substances, ions, gases can be seen between these three volumes. In the body, the main parameters of Uquid, such as pH, osmotic pressure and volume, are strictly controlled. The pH levels of the extracellular fluid and blood are the same, and are normally about 7.36. Several biological conformations of macromolecules and the catalytic activity of enzymes are dependent upon pH. The osmotic pressure of the extracellular fluid and blood plasma are similarly dependent. Hyaluronic acid of the extracellular matrix plays a very important role in maintaining these parameters within the physiological norms. As an intermediate between the external media and the cells, extracellular matrix performs the coordinative functions between the cells and different cellular structures. The functioning of the cell cytoplasmic membrane is directly dependent on the extracellular matrix. 

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