RESUMEN
<p><b>OBJECTIVE</b>To investigate the expression of connective tissue growth factor (CTGF) in osteoarthritis chondrocytes, and the relationship between CTGF, macrophage colony-stimulating factor (M-CSF) and cartilage degeneration.</p><p><b>METHODS</b>Ten New Zealand white rabbits were randomly divided into the normal group and OA model group established by Hulth's method. Sections were stained with Safranin O for histological examination. The cartilage histological characteristics were observed according to the method of Mankin. Immunohistochemical staining was performed. Articular cartilages were observed with microscopy and the image analysis method was used to measure the expression intensity of CTGF and M-CSF in each group, and the correlations of the expression of CTGF, M-CSF and cartilage degeneration were analyzed by statistics.</p><p><b>RESULTS</b>Immunohistochemical staining indicated that the expression intensity of CTGF, M-CSF in untreated group was significantly increased as compared with that in the normal group (P<0.05). Statistical analysis showed that there was a correlation between the expression of CTGF, M-CSF and cartilage degeneration (r=0.634, r=0.542, P<0.01 respectively).</p><p><b>CONCLUSION</b>The expression of CTGF and M-CSF protein is up regulated in osteoarthritis chondrocytes, which suggests that the activation of M-CSF is involved in the production of CTGF. CTGF and M-CSF play an important role in the pathogenesis of cartilage degeneration.</p>