Takada Y, Kusuda M, Hiura K, Sato T, Mochizuki H, Nagao Y, Tomura M, Yahiro M, Hakeda Y, Kawashima H
Technical Research Institute, Snow Brand Milk Products Co., Saitama, Japan.
Bone Miner. 1992 Jun;17(3):347-59. doi: 10.1016/0169-6009(92)90785-c.
To determine osteoclastic bone resorption we established a simple assay system in which unfractionated cells obtained from femora of 13-day-old mice were cultured on a dentine slice and the number of osteoclasts and their induced pit area on the slices were measured. When the bone cells (1 x 10(5) cells/dentine slice) were cultured in the presence of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] or human parathyroid hormone (hPTH) for 4 days, at which time newly-formed osteoclasts were not detected, the pit area was dose-dependently increased, being a 4.3- or 4.1-fold respective increase over the control at a 10(-8) M concentration of hormones. Chick calcitonin (cCT) inhibited the osteoclastic bone resorption induced by either of these hormones. cCT alone also suppressed the bone resorption by the cells (3 x 10(5) cells/dentine slice). These findings indicate that 1,25(OH)2D3 or hPTH may mainly activate pre-existing osteoclasts, resulting in increased bone resorption, and that cCT may suppress this osteoclastic activity. When 1,25(OH)2D3 or hPTH was added to the cells pre-cultured in factor-free medium for 6 days, at which time pre-existing osteoclasts had almost degenerated, new osteoclasts were formed, resulting in an increase in pit formation. Thus this system is a useful method which could more sensitively evaluate the effects of hormones or factors on osteoclast formation and activation than other previous systems.
为了确定破骨细胞介导的骨吸收，我们建立了一个简单的检测系统，将从13日龄小鼠股骨中获取的未分离细胞培养在牙本质切片上，然后测量切片上破骨细胞的数量及其诱导形成的凹陷面积。当骨细胞（1×10⁵个细胞/牙本质切片）在1,25 - 二羟维生素D3 [1,25(OH)₂D3] 或人甲状旁腺激素（hPTH）存在的情况下培养4天时，此时未检测到新形成的破骨细胞，凹陷面积呈剂量依赖性增加，在激素浓度为10⁻⁸ M时，分别比对照增加4.3倍或4.1倍。鸡降钙素（cCT）可抑制这两种激素诱导的破骨细胞骨吸收。单独使用cCT也可抑制细胞（3×10⁵个细胞/牙本质切片）介导的骨吸收。这些结果表明，1,25(OH)₂D3或hPTH可能主要激活预先存在的破骨细胞，从而导致骨吸收增加，而cCT可能抑制这种破骨细胞活性。当将1,25(OH)₂D3或hPTH添加到在无因子培养基中预培养6天的细胞中时，此时预先存在的破骨细胞几乎退化，新的破骨细胞形成，导致凹陷形成增加。因此，该系统是一种有用的方法，与之前的其他系统相比，它可以更敏感地评估激素或因子对破骨细胞形成和激活的影响。
