Preparation and Determination of Rabbit Knee Osteoarthritis Model

OBJECTIVE To establish rabbit knee osteoarthritis models and to observe the degeneration of cartilage tissue and cartilage cells. METHODS 12 healthy male rabbits， weighing 2.0~3.0 kg， were randomly divided into sham operation group and model group， 6 in each group. Anterior cruciate ligament and medial collateral ligament were cut off in the right knee medial longitudinal incision and medial meniscus was resected， which was sutured by serial layers. 2×10⁵ U of penicillin were intramuscularly injected daily for 7 days to prevent inflammation. The rabbits were forced to exercise for 60 minutes a day; after 12 weeks， they were killed and the complete knees were taken out as experimental samples. They were processed with morphological analysis and the two groups were conducted in cell culture to observe the morphological characteristics of rabbit chondrocytes. RESULTS The histological analysis was that safranine fast green staining in sham operation group showed articular cartilage surface in normal group was smooth， flat， evenly distributed， aligned and clear of all layers; model group showed articular cartilage surface cracked， some part impaired， cartilage cells significantly reduced， cartilage level dyed uneven， and even the local unstained. Chondrocytes cultured in sham operation group were mostly fusiform or short spindle with a small part polygonal and nuclei circular or oval; expression of type Ⅱcollagen significantly reduced. CONCLUSION Rabbit knee osteoarthritis models are successfully established and analyzed first with modern techniques. The model operates simply and has a good repeatability， which lays a foundation for further study of TCM preventing and treating knee osteoarthritis.