Møller S E, Kirk L, Honoré P
Psychopharmacology (Berl). 1982;76(1):79-83. doi: 10.1007/BF00430761.
The concentration of free and total tryptophan and kynurenine in plasma from 49 female depressives and 26 female controls was measured following oral loading with L-tryptophan, 100 mg/kg body weight. There was no significant difference between five depressives and six controls in the area under curve for free or total tryptophan or kynurenine in plasma. The peak concentration of kynurenine occurred 4 h after loading and in correlated significantly with the area under curve for kynurenine. There was no significant correlation between the L-tryptophan dose (g) and the plasma concentration of kynurenine a 4 h in the 49 depressives or 26 controls. The mean plasma levels of tryptophan and kynurenine at 4 h in the depressives were not significantly different from control levels. There was no clear relationship between the plasma levels of tryptophan or kynurenine at 4 h and the therapeutic response in 13 depressives treated with L-tryptophan for 15 days. It is concluded that the absorption, the plasma clearance, and the degradation to kynurenine of loading doses of L-tryptophan are normal in depressed patients. Results furthermore suggest that the plasma levels of tryptophan and kynurenine at 4 h are poor predictors of the response to L-tryptophan treatment in depressives.
对49名女性抑郁症患者和26名女性对照者口服100mg/kg体重的L-色氨酸后，测定其血浆中游离色氨酸、总色氨酸和犬尿氨酸的浓度。5名抑郁症患者和6名对照者血浆中游离色氨酸、总色氨酸或犬尿氨酸的曲线下面积无显著差异。犬尿氨酸的峰值浓度在给药后4小时出现，且与犬尿氨酸的曲线下面积显著相关。在49名抑郁症患者或26名对照者中，L-色氨酸剂量（克）与4小时时血浆中犬尿氨酸浓度之间无显著相关性。抑郁症患者4小时时色氨酸和犬尿氨酸的平均血浆水平与对照水平无显著差异。在13名接受L-色氨酸治疗15天的抑郁症患者中，4小时时色氨酸或犬尿氨酸的血浆水平与治疗反应之间没有明确的关系。结论是，抑郁症患者中，负荷剂量的L-色氨酸的吸收、血浆清除率以及向犬尿氨酸的降解是正常的。此外，结果表明，4小时时色氨酸和犬尿氨酸的血浆水平不能很好地预测抑郁症患者对L-色氨酸治疗的反应。
