In vitro calcium deposition by rachitic rat matrix vesicles: nucleoside triphosphate supported calcium deposition.
In vitro calcium deposition by rachitic rat matrix vesicles: nucleoside triphosphate supported calcium deposition.
复制标题
佝偻病大鼠基质囊泡的体外钙沉积：核苷三磷酸支持钙沉积。
DOI：
10.1016/0304-4165(92)90015-m
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Hsu,HH
中科院分区：
文献类型：
--
作者：
Hsu,HH
本研究旨在测试血清水平的ATP是否可以支持基质囊泡介导的Ca沉积，而最终的Ca × P离子产物维持在或低于血清或软骨液水平。佝偻病大鼠骺软骨基质囊泡（40 μg蛋白质/ml）在含有50 mM Tris（pH 7.6，37 ℃）、0.1 M NaCl、1.35 mM CaCl 2、1 mM ATP的简单钙化溶液（无外源性添加的Pi）中，5小时后沉积约500 nmol Ca/mg蛋白质。随着孵育时间的增加，钙沉积量增加，ATP，Ca 2+，氢氧化物和基质囊泡蛋白，UTP，GTP和CTP的浓度同样有效地支持钙沉积的基质囊泡。ATP-α-β-亚甲基和ATP-β，γ-亚甲基抑制ATP依赖性钙沉积。在钙化溶液中ATP和Ca ~（2+）含量有限的情况下，实验表明，在血清或软骨液水平存在Ca × P离子产物的情况下，血清水平的ATP浓度可以支持基质囊泡介导的Ca沉积。
The present study was designed to test whether ATP at serum levels can support matrix vesicle-mediated Ca deposition while the final Ca × P ion product is maintained at or below serum or cartilage fluid levels. Rachitic rat epiphyseal cartilage matrix vesicles (40 μg protein/ml) in a simple calcifying solution (without exogenously added Pi) containing 50 mM Tris, pH 7.6 at 37†C, 0.1 M NaCl, 1.35 mM CaCl2, 1 mM ATP, deposited about 500 nmol Ca/mg protein after 5 h. The amount of Ca deposited increased with increases in incubation time, concentrations of ATP, Ca2+, hydroxide, and matrix vesicle protein, UTP, GTP, and CTP were equally effective in supporting Ca deposition by matrix vesicles. ATP-α-β-methylene and ATP-β,γ-methylene were inhibitory for ATP-dependent Ca deposition. Experiments with limiting amounts of ATP and Ca2+availble in the calcifying solution indicated that ATP concentration at serum levels, in the presence of Ca × P ion products at serum or cartilage fluid levels, can support matrix vesicle-mediated Ca deposition.