Giers Morgan B, Munter Bryce T, Eyster Kyle J, Ide George D, Newcomb Anna G U S, Lehrman Jennifer N, Belykh Evgenii, Byvaltsev Vadim A, Kelly Brian P, Preul Mark C, Theodore Nicholas
Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
School of Biological and Health Systems Engineering, Arizona State University, Tempe, Arizona, USA.
World Neurosurg. 2017 Mar;99:395-402. doi: 10.1016/j.wneu.2016.12.041. Epub 2016 Dec 21.
Physical data are lacking on nutrient transport in human intervertebral discs (IVDs), which support regeneration. Our objective was to study nutrient transport in porcine IVDs to determine the effects of biomechanical and physiological factors.
In vitro testing of whole porcine IVDs was performed under different loading conditions. Fifty cervical, thoracic, and lumbar discs with attached end plates were removed from 4 Yorkshire pigs (90-150 lbs). Discs were placed in Safranin O or Fast Green FCF histological stains in diffusion or diurnal compression-tested groups. The end plate was studied by the use of polyurethane to block it. Traction was studied with a mechanical testing frame. Discs were cut transversely and photographed. Images were analyzed for depth of annulus fibrosus (AF) stained. The nucleus pulposus (NP) was assigned a staining score.
Results showed no difference in AF staining between the 2 stains (P = 0.60). The depth of AF staining did not increase (P = 0.60) due to convection or disc height change via diurnal loading. The NP in all open end plate samples was stained completely by day 3. NP staining was decreased in blocked end plate samples (P = 0.07) and AF staining was significantly less in traction samples than in diffusion-only samples (P = 0.04).
This method showed that most small molecule nutrient transport occurs via the end plate. Compressive load was a negligible benefit or hindrance to transport. Traction hindered transport in the short term. This method can be used to study strategies for increasing nutrient transport in IVDs.
目前缺乏关于支持再生的人体椎间盘（IVD）营养物质运输的物理数据。我们的目标是研究猪IVD中的营养物质运输，以确定生物力学和生理因素的影响。
在不同加载条件下对完整的猪IVD进行体外测试。从4头约克夏猪（90 - 150磅）身上取出50个带有附着终板的颈椎、胸椎和腰椎椎间盘。将椎间盘置于番红O或固绿FCF组织学染色剂中，分为扩散组或昼夜压缩测试组。通过使用聚氨酯封闭终板来研究终板。用机械测试框架研究牵引。将椎间盘横向切割并拍照。分析图像中纤维环（AF）染色的深度。髓核（NP）被赋予一个染色分数。
结果显示两种染色剂之间的AF染色无差异（P = 0.60）。由于对流或昼夜加载导致的椎间盘高度变化，AF染色深度没有增加（P = 0.60）。在所有开放终板样本中，NP在第3天完全被染色。封闭终板样本中的NP染色减少（P = 0.07），并且牵引样本中的AF染色明显少于仅扩散样本（P = 0.04）。
该方法表明，大多数小分子营养物质运输通过终板进行。压缩负荷对运输的益处或阻碍可忽略不计。短期来看，牵引会阻碍运输。该方法可用于研究增加IVD中营养物质运输的策略。
