Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.
J Anat. 2013 Mar;222(3):341-8. doi: 10.1111/joa.12022. Epub 2013 Jan 13.
The intervertebral disc is an avascular tissue, maintained by a small population of cells that obtain nutrients mainly by diffusion from capillaries at the disc-vertebral body interface. Loss of this nutrient supply is thought to lead to disc degeneration, but how nutrient supply influences viable cell density is unclear. We investigated two factors that influence nutrient delivery to disc cells and hence cell viability: disc height and blood supply. We used bovine caudal discs as our model as these show a gradation in disc height. We found that although disc height varied twofold from the largest to the smallest disc studied, it had no significant effect on cell density, unlike the situation found in articular cartilage. The density of blood vessels supplying the discs was markedly greater for the largest disc than the smallest disc, as was the density of pores allowing capillary penetration through the bony endplate. Results indicate that changes in blood vessels in the vertebral bodies supplying the disc, as well as changes in endplate architecture appear to influence density of cells in intervertebral discs.
椎间盘是一种无血管组织，由一小部分细胞维持，这些细胞主要通过椎间盘-椎体界面处的毛细血管扩散来获取营养。人们认为营养供应的丧失会导致椎间盘退化，但营养供应如何影响存活细胞密度尚不清楚。我们研究了两个影响椎间盘细胞营养供应从而影响细胞活力的因素：椎间盘高度和血液供应。我们使用牛尾椎间盘作为模型，因为这些椎间盘的高度存在梯度变化。我们发现，尽管研究的最大和最小椎间盘之间的椎间盘高度相差两倍，但与关节软骨的情况不同，它对细胞密度没有显著影响。为最大的椎间盘供血的血管密度明显大于最小的椎间盘，允许毛细血管穿透骨终板的孔密度也是如此。结果表明，供应椎间盘的椎体中的血管变化以及终板结构的变化似乎会影响椎间盘细胞的密度。
