Wilson J W, Werness P G, Smith L H
J Urol. 1985 Dec;134(6):1255-8. doi: 10.1016/s0022-5347(17)47706-8.
Pyrophosphate, citrate and magnesium, inhibitors of hydroxyapatite crystal growth, were studied using a seeded crystal growth system of constant composition at pH 5.80, 6.60 and 7.40. With this technique, crystal growth was studied at constant supersaturation at different pH values without the induction of other calcium phosphate phases. One inhibitor unit (that concentration of material that results in a reduction of 50 per cent in the growth rate from control) was calculated using the Langmuir adsorption isotherm. Pyrophosphate and citrate increased inhibitor activity with decreasing pH, whereas magnesium increased inhibitor activity with increasing pH. These data suggest that, at the urinary concentrations of these inhibitors, pyrophosphate is the most potent inhibitor, citrate less, and magnesium least. Pooled urine collections were studied using the same system and were found to have decreased inhibitor activity as pH decreased. This suggests that other modulators of hydroxyapatite, either promoters or inhibitors, are active in this system at the pH values studied.
使用恒定组成的晶种生长系统，在pH值为5.80、6.60和7.40的条件下，对羟基磷灰石晶体生长的抑制剂焦磷酸盐、柠檬酸盐和镁进行了研究。采用该技术，在不同pH值下的恒定过饱和度条件下研究晶体生长，而不诱导其他磷酸钙相。使用朗缪尔吸附等温线计算一个抑制剂单位（即导致生长速率比对照降低50%的物质浓度）。焦磷酸盐和柠檬酸盐随着pH值降低而增加抑制剂活性，而镁随着pH值升高而增加抑制剂活性。这些数据表明，在这些抑制剂的尿液浓度下，焦磷酸盐是最有效的抑制剂，柠檬酸盐次之，镁最少。使用相同系统对混合尿液样本进行了研究，发现随着pH值降低，抑制剂活性降低。这表明在研究的pH值下，羟基磷灰石的其他调节剂，无论是促进剂还是抑制剂，在该系统中都具有活性。
