Studies on the matrix resicles of the odontoblast layer and cementoblast layer of bovine tooth germs.

牛牙胚成牙本质细胞层和成牙骨质细胞层基质基质的研究。

• 批准号: 10671945
• 负责人: MAKI Kenshi
• 金额: $ 1.41万
• 依托单位: Kyushu Dental College
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10671945/
• 关键词: Matrix resicles; Odontoblast; Alkaline phosphatase; Lactate dehydrogenase; metallo protease; セメント芽細胞層; Alkaline phosphatase; Lactate dehydrogenase; 乳酸脱水素酵素

Matrix vesicles are extracelluar organelles that initiate mineralization in the extracelluler matrix of various calcifing tissues. The dentin was removed from bovine tooth germs. The matrix vesicle fractions, obtained by collagenase digestion and differential centrifugation, were subjected to sucrose-density-gradient centrifugation. Alkaline phosphatase activity(ALP) , protease activity, and lactate dehydrogenase activity (LDH) were assayed for the marker enzyme of matrix vesicles.1. There were not only the matrix vesicle but also matrix vesicle-like-vesicle with a high density in the dentin, the vesicle contained ALP and LDH but did not protease.2. Protease activity after inhibition with o-phenanthroline was restored by the addition of CoィイD12+ィエD1 and ZnィイD12+ィエD1, These results show that the protese in the matrix vesicles of the odontoblasts and predentin is a nietalloprotese.3. Aldolase, aspartate : 2-oxoglutarate aminotransferase and alanine : 2-oxoglutarate aminotransferase,cytosonic enzymes except LDH ,were not detected in these vesicles. These results suggest the presence of a mechanism for the specific uptake of cytosolic LDH.

基质囊泡是细胞外细胞器，其启动各种钙化组织的细胞外基质中的矿化。从牛牙胚中去除牙本质。将通过胶原酶消化和差速离心获得的基质囊泡级分进行蔗糖密度梯度离心。测定基质囊泡标志酶的碱性磷酸酶活性(ALP)、蛋白酶活性、乳酸脱氢酶活性(LDH)。 1．牙本质中不仅存在基质囊泡，而且还存在高密度的基质囊泡样囊泡，囊泡中含有ALP和LDH，但不含蛋白酶。2．添加CoィイD12+ィエD1和ZnィイD12+ィエD1可恢复邻菲咯啉抑制后的蛋白酶活性。这些结果表明，成牙本质细胞和前牙本质的基质囊泡中的蛋白酶是nietalloprotese。 3．在这些囊泡中未检测到醛缩酶、天冬氨酸：2-酮戊二酸转氨酶和丙氨酸：2-氧戊二酸转氨酶、细胞超声酶（LDH除外）。这些结果表明存在一种胞质 LDH 特异性摄取的机制。