Ohya K, Meyer J L, Felix R, Fleisch H
Department of Pathophysiology, University of Bern, Switzerland.
Clin Orthop Relat Res. 1988 Jul(232):119-26.
Inhibition of calcium phosphate crystal formation was assessed in conditioned medium from cultured rat calvaria and rat calvaria cells. The amount of inhibitor activity was measured by determining the amount of hydroxyapatite needed to induce calcium phosphate precipitation in a solution with a constant calcium phosphate supersaturation. Rat calvaria in culture released inhibitor activity. This activity was separated by chromatography on a Bio-Gel P4 column into a high molecular weight (HMW) fraction and a low molecular weight (LMW) fraction. The latter contained, among others, citrate and pyrophosphate (PPi), but the concentration of these was too low to account for the total activity observed. The identity of the HMW and the remaining LMW inhibitors are at present unknown. Various populations of calvaria cells also produced these two types of inhibitors, 20% of the LMW being due to PPi. Fibroblasts produced only the HMW type of inhibitors. These results suggest that cells might control the process of biologic calcification by regulating the amount of inhibitors they produce.
在培养的大鼠颅骨及大鼠颅骨细胞的条件培养基中评估了磷酸钙晶体形成的抑制情况。通过测定在具有恒定磷酸钙过饱和度的溶液中诱导磷酸钙沉淀所需的羟基磷灰石量来测量抑制剂活性。培养中的大鼠颅骨释放出抑制剂活性。该活性通过在Bio-Gel P4柱上进行色谱分离，分为高分子量（HMW）部分和低分子量（LMW）部分。后者除其他成分外还含有柠檬酸盐和焦磷酸盐（PPi），但其浓度过低，无法解释所观察到的全部活性。目前尚不清楚HMW和其余LMW抑制剂的具体成分。各种颅骨细胞群体也产生这两种类型的抑制剂，LMW的20%归因于PPi。成纤维细胞仅产生HMW类型的抑制剂。这些结果表明，细胞可能通过调节其产生的抑制剂数量来控制生物钙化过程。
