Roullet J B, Lacour B, Ulmann A, Bailly M
Clin Chem. 1982 Jan;28(1):134-7.
We describe a simple, rapid, and fully automated technique for measuring urinary pyrophosphates with a centrifugal analyzer (the ENI GEMSAEC). This technique depends on the enzymic magnesium-dependent reaction with UDPG pyrophosphorylase (UTP: alpha-D-glucose-1-phosphate uridylyl transferase, EC 2.7.7.9) and spectrophotometry of the NADPH formed in a combined system of phosphorylation and reduction. Many samples of urine can be analyzed quickly without pretreatment, with high sensitivity (1.3 mA/mumol of substrate) and good reproducibility. The mean within-run coefficient of variation for a 50 mumol/L pyrophosphate solution was 1.4%. We determined the optimum enzyme and magnesium concentrations necessary for use in a 4-min reaction. Because there is no inhibitory effect of chloride and phosphate ions, pyrophosphate can be measured directly in urine, without prior extraction. With this technique, the mean value (and SD) for urinary pyrophosphate excretion by 30 healthy subjects was 39.3 (SD 17.2) mumol/24 h.
我们描述了一种使用离心分析仪（ENI GEMSAEC）测量尿焦磷酸盐的简单、快速且全自动的技术。该技术依赖于与UDPG焦磷酸化酶（UTP：α-D-葡萄糖-1-磷酸尿苷酰转移酶，EC 2.7.7.9）的酶促镁依赖性反应以及在磷酸化和还原联合系统中形成的NADPH的分光光度法。许多尿液样本无需预处理即可快速分析，具有高灵敏度（1.3 mA/μmol底物）和良好的重现性。50 μmol/L焦磷酸盐溶液的批内变异系数平均值为1.4%。我们确定了在4分钟反应中使用所需的最佳酶和镁浓度。由于氯离子和磷酸根离子没有抑制作用，焦磷酸盐可以直接在尿液中测量，无需事先提取。采用该技术，30名健康受试者尿焦磷酸盐排泄的平均值（及标准差）为39.3（标准差17.2）μmol/24小时。
