AN IMMUNOHISTOCHEMICAL STUDY OF THE LOCALIZATION OF BIGLYCAN, DECORINAND LARGE CHONDROITIN-SULFATE PROTEOGLYCAN IN ADULT-RAT TEMPOROMANDIBULAR-JOINT DISC

To analyse regional variations in extracellular matrix components of a dult rat temporomandibular joint discs, immunohistochemical techniques were used to examine the localization of two small dermatan-sulphate proteoglycans, biglycan and decorin, and a large chondroitin-sulphate proteoglycan. Staining for biglycan was intense in the posterior band, although it had a rather weak and even distribution throughout the di sc. In contrast, staining for decorin was faint in the intermediate zo ne and the central part of the posterior band, moderate in the anterio r and posterior attachments and most intense in the junction between t he anterior band and attachment. The upper surface of the disc stained more intensely than the lower. Similarly, there was intense staining for large chondroitin-sulphate proteoglycan in the peripheral band, bu t both the anterior and the temporal parts of the posterior attachment s were faintly stained. These results demonstrate marked regional diff erences in the expression of biglycan, decorin and large chondroitin-s ulphate proteoglycan in the temporomandibular joint discs of adult rat s. These variations probably reflect the different biomechanical envir onments caused by the complicated articulatory functions of the tempor omandibular joint. (C) 1998 Elsevier Science Ltd. All rights reserved.