Degenerative changes of the cranial cruciate ligament harvested from dogswith cranial cruciate ligament rupture

[摘要] References(29)Degenerative cranial cruciate ligament (CCL) rupture is characterized histologically bydegenerating extracellular matrix (ECM) and chondroid metaplasia. Here, we describe theprogression of chondroid metaplasia and the changes in the expression of ECM components incanine CCL rupture (CCLR). CCLs from 26 stifle joints with CCLR (CCLR group) and normalCCLs from 12 young beagles (control group) were examined histologically andimmunohistochemically for expression of type I (COLI), type II (COLII), type III collagen(COLIII) and Sry-type HMG box 9 (SOX9). Cell density and morphology of CCLs werequantified using hematoxylin–eosin staining. The percentage of round cells was higher inthe CCLR group than in controls. COLI-positive areas were seen extensively in theconnecting fibers, but weakly represented in the cytoplasm of normal CCLs. In the CCLRgroup, there were fewer COLI-positive areas, but many COLI-positive cells. The percentagesof COLII-, COLIII- and SOX9-positive cells were higher in the CCLR group than in controls.The number of spindle cells with perinuclear halo was high in the CCLR group, and most ofthese cells were SOX9-positive. Deposition of COLI, the main ECM component of ligaments,decreased with increased COLIII expression in degenerated CCL tissue, which shows that thedeposition of the ECM is changed in CCLR. On the contrary, expression of SOX9 increased,which may contribute to the synthesis of cartilage matrix. The expression of COLII andSOX9 in ligamentocytes showed that these cells tend to differentiate intochondrocytes.

[学科分类] 兽医学

[关键词] cranial cruciate ligament disease;SOX9;type I collagen;type II collagen;type III collagen