Rose D P, Adams P W
J Clin Pathol. 1972 Mar;25(3):252-8. doi: 10.1136/jcp.25.3.252.
The effect upon tryptophan metabolism of the use of combined oestrogen-progestagen oral contraceptives containing a low (0.05 mg) dose of oestrogen, or of the continuous administration of megestrol acetate, has been studied by determining the excretion of tryptophan metabolites in urine collected after a 2 g oral dose of the amino acid. An investigation of 10 women before being given oral contraceptives and after 21 days and three months of their use showed that xanthurenic acid excretion is increased within 21 days and that by three months the urinary levels of xanthurenic acid, kynurenine, 3-hydroxykynurenine, and 3-hydroxyanthranilic acid may all be elevated. Ten other women studied after taking a combined type of oral contraceptive for six months or longer excreted significantly higher levels of all four metabolites than did those who had been treated with these steroids for only three months. The abnormal urinary excretion of tryptophan metabolites was completely reversed by treatment with pyridoxine hydrochloride, 20 mg daily for one month. Studies of four women when they were taking an oestrogen-containing oral contraceptive and at intervals after they had discontinued its use showed that abnormal tryptophan metabolism may persist for three months or longer. Megestrol acetate, a progestagen used as an oral contraceptive, was found to have no significant effect upon tryptophan metabolism.The possible clinical significance of the effects of oral contraceptives upon tryptophan metabolism is discussed.
通过测定口服2克色氨酸后收集的尿液中色氨酸代谢产物的排泄情况，研究了含低剂量（0.05毫克）雌激素的复方雌激素 - 孕激素口服避孕药或醋酸甲地孕酮持续给药对色氨酸代谢的影响。对10名女性在服用口服避孕药前以及服用21天和三个月后的情况进行调查发现，21天内黄尿酸排泄增加，到三个月时，黄尿酸、犬尿氨酸、3 - 羟基犬尿氨酸和3 - 羟基邻氨基苯甲酸的尿液水平可能都会升高。另外10名服用复方口服避孕药六个月或更长时间的女性排泄的所有四种代谢产物水平明显高于仅服用这些甾体激素三个月的女性。色氨酸代谢产物的异常尿排泄通过每天服用20毫克盐酸吡哆醇治疗一个月完全逆转。对四名女性在服用含雌激素口服避孕药时以及停药后的不同时间间隔进行研究表明，异常色氨酸代谢可能持续三个月或更长时间。发现用作口服避孕药的孕激素醋酸甲地孕酮对色氨酸代谢没有显著影响。本文讨论了口服避孕药对色氨酸代谢影响的可能临床意义。
