Detection of a small proteoglycan present in xiphoid cartilage regions submitted to different biomechanical forces

1. The effect of biomechanical forces on large proteoglycans and collagen of cartilage has deserved intensive study, enhancing the importance of these molecules to support a better distribution of compressive forces especially in articular cartilage. In the present study, other extracellular matrix components, non-collagenous proteins and small proteoglycans, have been evaluated in terms of biomechanical tension. 2. Different parts of chicken xiphoid cartilage, lateral (R and L) and central (C) portions, which bear different biomechanical tensions, were analyzed. DEAE-cellulose chromatography profiles were similar for R and L portions. SDS-PAGE analyses revealed proteins of 29, 60 and 70 kDa for R and L. The 20- and 70-kDa proteins were not detected in the C portion while the 60-kDa protein was present at a high level. 3. The differences found between lateral (R and L) and central portions of the xiphoid cartilage may be related to the structure of the cartilage which bears higher tension forces than the lateral parts.