Ohashi N, Yoshikawa M
Discovery Research Laboratory, Tanabe Seiyaku Company Limited, Toda-shi, Saitama, Japan.
J Chromatogr B Biomed Sci Appl. 2000 Sep 1;746(1):17-24. doi: 10.1016/s0378-4347(00)00201-2.
The isoprostane, 8-isoprostaglandin F2alpha (8-iso-PGF2alpha), is produced non-enzymatically by direct oxidation of arachidonic acid on the cell surface by oxygen radicals. We developed a new assay method for 8-iso-PGF2alpha using 2H4-8-iso-PGF2alpha as the internal standard (I.S.) by high-performance liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). For this assay, we established a very simple and rapid pretreatment method using a membrane filter-type solid-phase extraction column (Empore disk cartridge) for human urine extracts or intact plasma. LC-ESI-MS was performed in the selected ion monitoring (SIM) mode using target ions at m/z 353.24 (8-iso-PGF2alpha) and m/z 357.26 (I.S.) with a resolution of 1,500. The imprecision for this method was below 13.7%. Mean inaccuracy was 8.7% for added levels of 8-iso-PGF2alpha up to 5,000 pg/ml of urine and 500 pg/ml of plasma. Determination of plasma and urinary 8-iso-PGF2alpha concentrations in healthy subjects by the present method revealed that its urinary concentration in smokers tends to be higher than that in nonsmokers.
异前列腺素8-异前列腺素F2α（8-iso-PGF2α）是由氧自由基在细胞表面直接氧化花生四烯酸非酶促产生的。我们开发了一种新的8-iso-PGF2α检测方法，该方法使用2H4-8-iso-PGF2α作为内标（I.S.），通过高效液相色谱-电喷雾电离-质谱联用（LC-ESI-MS）进行检测。对于该检测，我们建立了一种非常简单快速的预处理方法，使用膜滤型固相萃取柱（Empore盘式柱）处理人尿液提取物或完整血浆。LC-ESI-MS采用选择离子监测（SIM）模式，使用m/z 353.24（8-iso-PGF2α）和m/z 357.26（I.S.）的目标离子，分辨率为1500。该方法的不精密度低于13.7%。对于尿液中添加水平高达5000 pg/ml以及血浆中添加水平高达500 pg/ml的8-iso-PGF2α，平均误差为8.7%。采用本方法测定健康受试者血浆和尿液中8-iso-PGF2α的浓度，结果显示吸烟者尿液中的浓度往往高于非吸烟者。
