Al-Qtaitat A, Shore R C, Aaron J E
Faculty of Biological Sciences, University of Leeds, UK.
J Musculoskelet Neuronal Interact. 2010 Mar;10(1):112-23.
The periosteum and Sharpey's fibre extensions occupy the musculoskeletal interface and may be strategic in age-related deterioration. Because of its exceptionally powerful insertions the porcine mandible is an ideal model and its periosteal system was compared in 4 separate regions of adult young (1 year) and older (3 year) animals. These were examined by undecalcified histology, collagen immunohistochemistry and mineral histochemistry using polarization, epifluorescence and laser confocal microscopy; mineral ultrastructure was facilitated by chromium labelling with EDX microanalysis. Birefringent Sharpey's fibres were coarse (>8 microm) or fine and classified as horizontal (more common with age), oblique (most common in youth) or vertical (least common); in addition they were designated "superficial", "transcortical" and "intertrabecular" (the latter being deep, coarse and vertical). Their specific affinity for collagen type III FITC-labelled antibody demonstrated 3-dimensional arrays of bone-permeating fibres. With age at each region the cortical thickness rose (e.g. 4.9 mm to 9.3 mm), the periosteum thinned (e.g. 180-/+7 microm to 129-/+8 microm; p<0.001), and the periosteum: bone ratio diminished (e.g. 3.65-/+0.36 to 1.40-/+0.14; p<0.001) while Sharpey's fibres became fewer, fragmented, superficial and shortened (e.g. 226-/+27 microm to 55-/+6 microm; p<0.001). Accompanying was the sporadic encroachment of calcified particles, 1 microm diameter, in irregular periosteal aggregates or interlinked around Sharpey bundles (resembling calcifying turkey leg tendon). EDX microanalysis confirmed prominent chromium spectral peaks in the older periosteum only, coincident with chromium-labelled mineral "ghosts". It was concluded that the periosteum and Sharpey's fibres, deep-penetrating and complex in youth, partially hardens and regresses with age with implications for its functional properties.
骨膜和沙比纤维延伸占据了肌肉骨骼界面，可能在与年龄相关的退化过程中起关键作用。由于猪下颌骨的附着异常牢固，它是一个理想的模型，研究人员比较了成年幼年（1岁）和老年（3岁）动物4个不同区域的骨膜系统。通过未脱钙组织学、胶原蛋白免疫组织化学和矿物质组织化学方法，利用偏光、落射荧光和激光共聚焦显微镜对这些区域进行了检查；通过用能量色散X射线微分析进行铬标记，有助于观察矿物质超微结构。双折射沙比纤维可分为粗（>8微米）或细两种，又可分为水平（随年龄增长更常见）、斜向（在年轻时最常见）或垂直（最不常见）；此外，它们还被分为“浅表型”、“穿皮质型”和“小梁间型”（后者较深、较粗且垂直）。它们对III型胶原蛋白异硫氰酸荧光素标记抗体的特异性亲和力显示出骨渗透纤维的三维排列。随着每个区域年龄的增长，皮质厚度增加（例如从4.9毫米增加到9.3毫米），骨膜变薄（例如从180±7微米变薄到129±8微米；p<0.001），骨膜与骨的比例降低（例如从3.65±0.36降低到1.40±0.14；p<0.001），而沙比纤维数量减少、断裂、浅表化且缩短（例如从226±27微米缩短到55±6微米；p<0.001）。同时，直径1微米的钙化颗粒偶尔侵入不规则的骨膜聚集体或围绕沙比纤维束相互连接（类似于钙化的火鸡腿肌腱）。能量色散X射线微分析仅在老年骨膜中证实了明显的铬光谱峰，与铬标记的矿物质“幽灵”一致。研究得出结论，骨膜和沙比纤维在年轻时深入且复杂，随着年龄增长会部分硬化和退化，这对其功能特性有影响。
