骨质疏松大鼠椎间盘的超微结构研究

Research of super microstructure in intervertebral discs of osteoporotic rats

目的 :观察骨质疏松大鼠椎间盘中髓核组织的超微结构改变 ,探讨其发病机理。方法 :6月龄雌性SD大鼠 6 4只 ,实验组 32只 ,行双侧卵巢切除术 ;对照组 32只 ,行假手术。术后 3个月两组分别以Prodigy骨密度仪作大鼠腰椎骨密度值 (BMD)测定 ;同时分别处死 5只大鼠 ,摘取子宫组织 ,进行病理学检查 ;术后 3个月分别取两组大鼠L4 L5椎间盘 ,应用电镜技术 ,对取出的髓核组织进行超微结构观察。结果 :术后 3个月大鼠腰椎BMD ,实验组和对照组之间有非常显著性的差异 (P <0 .0 1) ;同时实验组子宫病理学检查和对照组比较 ,明显萎缩。证实骨质疏松模型建立的成功。电镜结果显示 :(1)软骨细胞减少 ,多呈不同程度地退变、死亡 ,细胞外周致密颗粒增多。(2 )胶原纤维发生不同程度的变性、融合、扭结或钙化 ,胶原纤维束间裂隙增大。 (3)弹力纤维数量减少 ,伴老化、变性。结论

Objective: To observe the super microstructure in the nucleus pulposus of intervertebral discs of osteoporotic rats, and to study its episode mechanism. Methods: We randomly divided 64 SD rats of 6 months old into 2 groups. The experiment group received ovariectomy in both sides. The matched control group received false surgical operation. After 3 months, the bone mineral density (BMD) of the lunar vertebrae of the rats of 2 groups was measured with the Prodigy bone density machine. Pathologic examination was performed in tissues of uterus of 5 rats of 2 groups. The super microstructure was observed in the nucleus pulposus of the L 4 and L 5 intervertebral discs of rats in both groups. Results: Three months after the operation, significant difference was found in the BMD of the lunar vertebra of rats between the experiment group and the control group (P<0.01). Obvious atrophy was found in uterus tissues of rats in the experiment group. The result of the electron microscopy showed: (1) The number of the cartilage cells decreased, and the degeneration of retrograde or death occurred in most of the cells, the density granules of the cells increased. (2) The degeneration of retrograde, twists or calcifying occured in collagen fibers, and the gap of the collagen fibers enlarged. (3) The quantity of the elasticity fiber decrease, accompanying aging and degenerating. Conclusion: There is retrograde in the intervertebral discs of the osteoporotic rat.