双后肢大鼠椎间盘退变动物模型的建立

目的　为椎间盘相关研究建立一种经济科学的椎间盘退变动物模型。方法　对 15 2只新生SD大鼠采用截除双前肢和特殊饲养的方法培育双后肢大鼠 ,以 10只正常同龄大鼠作为对照 ,18月龄时处死后通过光镜和电镜检查来观察两组大鼠L2～ 3 椎间盘的退变情况。结果　截除双前肢后 ,双后肢大鼠生长良好 ,术后 18个月存活 17只。光镜检查证实其椎间盘均发生了严重的髓核和纤维环退变。有 2例还出现了腰椎间盘突出。超微结构观察发现髓核中脊索细胞出现明显的退变和坏死 ,软骨样细胞中出现大量脂滴。基质中胶原纤维排列紊乱 ,出现大量板层样结构和团块。而正常大鼠的椎间盘仅发生轻度退变 ,胶原纤维排列整齐。结论　本造模方法简单经济、成功率高、重复性好 ,建立的双后肢大鼠模型符合人体椎间盘退变规律。

The development of a degenerative disc animal model in bipedal rats

Objectives To develop a scientific and economical degenerative disc animal model for the study on the intervertebral disc.Methods The bipedal rats model was developed in 152 neonatal SD rats by forelimb amputation and special breeding methods.Ten normal rats in the same age served as the control.When the rats in the two groups were 18 months old,the L_ 2-3 disc was removed and observed under light and electron microscopy after the rats were sacrificed.Results After forelimb amputation,the bipedal rats grew well.Eighteen months after the operation,17 bipedal rats survived.Light microscopy revealed that the degeneration of the nucleus pulposus and annulus fibrosus was severe in bipedal rats' discs.Lumbar disc herniation was found in 2 bipedal rats.By ultrastructural examination on nucleus pulposus,obvious degeneration and necroses were found in the notochordal cells.Many fat drops were found in chondrocytelike cells.The collagen fibers in the matrix were irregular;large numbers of lamellar structures and mass appeared.Degeneration of the discs of the normal rats was gentle,and the arrangement of collagen fibers was in order.Conclusion This method of developing the animal model of disc degeneration is economical and easy.The degeneration procedure of the bipedal rats' discs is in agreement with that of human beings.