Vakkuri O, Tervo J, Luttinen R, Ruotsalainen H, Rahkamaa E, Leppäluoto J
Endocrinology. 1987 Jun;120(6):2453-9. doi: 10.1210/endo-120-6-2453.
A previously unknown melatonin metabolite was isolated by chloroform extraction and reverse phase HPLC from human and rat urine after administration of synthetic melatonin and characterized by mass spectroscopy and proton magnetic resonance spectroscopy to 1-acetyl-1,2,3,3a,8,8a-hexahydro-8a-hydroxy-5-methoxypyrrolo[2,3-b ]indole, a cyclic isomer of 2-hydroxymelatonin. This isolation was based on the fact that our melatonin antibody (a-MT-K1) cross-reacted against this novel metabolite at a level of 0.1% (melatonin 100%). In our HPLC program for indoles the cyclic 2-hydroxymelatonin eluted at 25 min, separately from synthetic indoles, between 6-hydroxymelatonin (19 min) and melatonin (35 min). In [3H] melatonin studies it was found to be present (at 25 min in our HPLC), accounting for 5% of the urinary metabolites of melatonin in the rat. Since beta-glucuronidase-arylsulfatase treatment of rat urine did not liberate the cyclic 2-hydroxymelatonin this would appear to be excreted into urine as the free form.
在给予合成褪黑素后，通过氯仿萃取和反相高效液相色谱法从人和大鼠尿液中分离出一种先前未知的褪黑素代谢物，并通过质谱和质子磁共振波谱对其进行表征，确定为1-乙酰基-1,2,3,3a,8,8a-六氢-8a-羟基-5-甲氧基吡咯并[2,3-b]吲哚，即2-羟基褪黑素的环状异构体。这种分离基于这样一个事实，即我们的褪黑素抗体（α-MT-K1）与这种新代谢物发生交叉反应的水平为0.1%（褪黑素为100%）。在我们针对吲哚的高效液相色谱程序中，环状2-羟基褪黑素在25分钟时洗脱，与合成吲哚分开，在6-羟基褪黑素（19分钟）和褪黑素（35分钟）之间。在[3H]褪黑素研究中发现它存在（在我们的高效液相色谱中于25分钟时出现），占大鼠尿液中褪黑素代谢物的5%。由于用β-葡萄糖醛酸酶-芳基硫酸酯酶处理大鼠尿液并未释放出环状2-羟基褪黑素，因此它似乎是以游离形式排泄到尿液中的。
