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Morphofunctional features of articular cartilage structure.

BACKGROUND
Articular cartilage is highly-organized nonvascularized tissue which is responsible in humans for pressure absorption under load, as well as for the smoothness of the opposite tangential bone surfaces. The purpose of our research is to study structural and functional features of articular cartilage at light- optical level by using state-of-the-art research methods of bone-cartilage tissue.


MATERIAL AND METHODS
the study was conducted on samples of femoral heads. Hyper fine sections were subject to hematoxylin and eosin, Van Gieson's and PAS staining. In order to identify the receptor profile of chondrocytes and the features of protein arrangement in extracellular matrix we undertook an immunohistochemical study.


RESULTS
An articular cartilage is quite organized tissue. As any other organ, it has parenchyma and stroma. Parenchyma is represented by one type of cells - chondrocytes, which, depending on how deep they are located in cartilage, have a different shape, size and functional features. The chondrocytes and extracellular matrix have different degrees of receptors expression.


CONCLUSIONS
the cartilage is being constantly self-renewed, what is manifested by means of a rather slow division of the surface-located chondrocytes and programmed death of dystrophic-modi ed cells. The features of extracellular matrix structure determine the originality of cell location in different areas of cartilage tissue. Due to synthesis of specific proteins, chondrocytes self-regulate properties of cartilage tissue.