Development of acetabulum and the content of bone morphogenetic protein 7 after local lesion of cartilago acetabularis in a rabbit model / 中国组织工程研究

ABSTRACT

BACKGROUND:In a primate model of ulna defect, exogenous recombinant human bone morphogenetic protein-7 can promote the healing of autologous bone defect. OBJECTIVE:To probe into the variation of the development of acetabulum and the content of bone morphogenetic protein 7 after local lesion of cartilage acetabularis in rabbits. METHODS:Thirty-six rabbits (4-week-old) were anesthetized to expose the left hip joint by the anterolateral approach. A 1.5 mm×2.0 mm×0.5 mm sample of the cartilago acetabularis was scraped from each rabbit as experimental group;and the right hip joint was also exposed as control group. To evaluate the hip development, X-rays were used at 4, 6, 8 weeks after the operation, 12 rabbits were kil ed randomly at 4, 6, 8 weeks after operation for general observation, histological examination and immunohistochemical assay. RESULTS AND CONCLUSION:By the radiographic examination, the acetabulums became shal ow and irregular in morphology. The shape of these femoral heads was applanate. Semiluxation and dislocation could be observed in some cases. Hematoxylin-eosin staining showed the regenerated fibrous tissue in the lesion region gradual y migrated from the meager layer to the deep layer to form fibrous cartilage, cartilage cells from proliferative and hypertrophic layers lost their normal columnar structure and arranged disorderly. Immunohistochemistry detection showed that over time, the dyeing of bone morphogenetic protein 7 became light in color. In the control group, a typical structure of articular hyaline cartilage was observed. The results suggest that damaging the cartilago acetabularis led to developmental hip dysplasia, and the content of bone morphogenetic protein 7 from al regions decreased by the extension of time.