Garland W A, Kuenzig W, Rubio F, Kornychuk H, Norkus E P, Conney A H
Cancer Res. 1986 Oct;46(10):5392-400.
Gas chromatography-high resolution mass spectrometry methods were developed for quantifying nitrosodimethylamine (NDMA) and nitrosoproline (NPRO) in human urine. The limits of quantitation of these methods, which utilize stable isotope analogues of NDMA and NPRO as internal standards, were 5 pg per ml for NDMA and 0.14 ng per ml for NPRO. The assays were used to quantify NDMA and NPRO in urine samples collected 4 times a wk for 5 wk from 24 healthy volunteers. The mean urinary excretion of NDMA during this time was found to be 38.2 ng per day, and the mean urinary excretion of NPRO was found to be 3.26 micrograms per day. Treatment of the volunteers with 600 mg of ascorbic acid and 100 IU of alpha-tocopherol 4 times a day for the final 3 wk of the study did not influence the urinary excretion of NDMA or NPRO. Considerable person-to-person and day-to-day variations were observed for the urinary excretion of both nitrosamines, but the urinary excretion of NDMA was not correlated with the urinary excretion of NPRO. Person-to-person and day-to-day differences in the urinary excretion were greater for NPRO than for NDMA. The mean urinary excretion of NDMA by the 24 subjects was as much as 5-fold higher on some days than on other days, but this was not observed for NPRO. Day-to-day differences in the mean urinary excretion of NDMA were correlated with the concentrations of nitrogen dioxide in the air.
开发了气相色谱-高分辨率质谱法用于定量测定人尿液中的亚硝基二甲胺（NDMA）和亚硝基脯氨酸（NPRO）。这些方法利用NDMA和NPRO的稳定同位素类似物作为内标，其定量限分别为NDMA每毫升5皮克和NPRO每毫升0.14纳克。该检测方法用于对24名健康志愿者每周采集4次、持续5周的尿液样本中的NDMA和NPRO进行定量。在此期间，NDMA的平均尿排泄量为每天38.2纳克，NPRO的平均尿排泄量为每天3.26微克。在研究的最后3周，让志愿者每天4次服用600毫克抗坏血酸和100国际单位α-生育酚，这并未影响NDMA或NPRO的尿排泄。观察到两种亚硝胺的尿排泄存在相当大的个体差异和每日差异，但NDMA的尿排泄与NPRO的尿排泄不相关。NPRO的尿排泄在个体间和每日的差异比NDMA更大。24名受试者的NDMA平均尿排泄量在某些日子比其他日子高出多达5倍，但NPRO未观察到这种情况。NDMA平均尿排泄量的每日差异与空气中二氧化氮的浓度相关。
