Differential involvement of matrix vesicles during the initial and appositional mineralization processes in bone, dentin, and cementum
Differential involvement of matrix vesicles during the initial and appositional mineralization processes in bone, dentin, and cementum
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DOI：
10.1016/s8756-3282(00)00243-x
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发表时间：
2000-04-01
期刊：
影响因子：
4.1
通讯作者：
Terashima, T
中科院分区：
文献类型：
--
作者：
Takano, Y;Sakai, H;Terashima, T
研究了大鼠骨和牙硬组织中基质囊泡的分布及其在生物矿化中的作用。每日给予强效矿化抑制剂1-羟乙基二膦酸酯（HEBP） 7天或14天。除牙髓周围牙本质外，受hebp影响的骨和牙中胚层硬组织中新形成的非矿化基质含有大量矿物质填充的基质囊泡（MV），随机分布在胶原基质中。在颅骨、干骺端小梁骨、牙槽骨和细胞骨质的hebp影响基质中，矿物质填充MV的分布密度为每100 μ m 60 ~ 70个(2)，数值之间无统计学差异。然而，在受hebp影响的牙本质中，MV仅位于地幔牙本质的非矿化基质中，而在牙髓周围的牙本质层中完全没有，相反，hebp影响的牙本质含有密集的富含钙和磷的非胶原基质。类似的网状结构在其他受HEBP影响的硬组织的非矿化基质中检测不到。这些观察结果表明，一定数量的MV（每100 μ m 60-70个）参与了大多数中胚层硬组织的对位矿化过程，除了在这些组织的初始矿物质诱导中发挥众所周知的作用。牙髓周围牙本质似乎是一个例外，在那里，相对矿化过程不需要MV。在没有MV的情况下，牙本质磷蛋白必须在牙髓周围的牙本质层中进行排他定位，以促进钙化前沿的对位矿化。（骨26:33 -339；2000）(C) 2000由爱思唯尔科学公司。版权所有。
The distribution of matrix vesicles and its role in biological mineralization were examined in bone and dental hard tissues of the rat after daily administrations of 1-hydroxyethylidene-1,1-bisphosphonate (HEBP), a potent inhibitor of mineralization, for 7 or 14 days. Newly formed, nonmineralized matrices of the HEBP-affected bone and mesodermal dental hard tissues other than circumpulpal dentin contained numerous mineral-filled matrix vesicles (MV), randomly distributed throughout the collagenous matrix. The distribution density of the mineral-filled MV in the HEBP-affected matrices of calvaria, metaphyseal trabecular bone, alveolar bone, and cellular cementum ranged from 60 to 70 per 100 mu m(2), and no statistically significant differences were noted among the values. In the HEBP-affected dentin, however, MV were located only in the nonmineralized matrix of mantle dentin and totally absent in the circumpulpal dentin layers, Instead, the HEBP-affected circumpulpal dentin contained a dense meshwork of noncollagenous matrix enriched with calcium and phosphorus. Comparable meshwork structures were undetectable in nonmineralized matrices of the other hard tissues affected by HEBP. These observations suggest that a certain population of MV (60-70 per 100 mu m(2)) is involved in the process of appositional mineralization in most of the mesodermal hard tissues, in addition to their well-known role in initial mineral induction in these tissues. Circumpulpal dentin appears to be an exception, where MV are not required for the appositional mineralization process. Exclusive localization of dentin phosphoproteins in circumpulpal dentin layers must take place to facilitate appositional mineralization at the calcification front, in the absence of MV. (Bone 26:333-339; 2000) (C) 2000 by Elsevier Science Inc. All rights reserved.