Hattori M, Kotake Y, Kotake Y
Acta Vitaminol Enzymol. 1984;6(3):221-8.
Xanthurenic acid (XA), kynurenic acid (KA) and creatinine in fasting urine were determined by reversed phase high pressure liquid chromatography in order to investigate the distortion of tryptophan metabolites in diabetes mellitus. The results of ten patients with non-insulin dependent diabetes mellitus and ten normal healthy subjects were compared. No tryptophan load test was performed in this study, because tryptophan loading produces further latent shortage of active vitamin B6 which results in exacerbation of the disease. The ratios of XA to KA and to creatinine were 0.35 +/- 0.099 (mean +/- S.D.) and 0.99 +/- 0.321 in the diabetic patients. The corresponding figures in the normal subjects were 0.17 +/- 0.064 and 0.55 +/- 0.22. Both ratios were significantly higher in the diabetic patients than in normal subjects (p less than 0.001 and p less than 0.01, respectively). This means that XA was excessively excreted in diabetic patients resulting in distortion of tryptophan metabolism. Our findings indicated that the ratios are useful to monitor excess XA excretion and also for detection of diabetes.
为了研究糖尿病患者色氨酸代谢产物的异常情况，采用反相高效液相色谱法测定空腹尿中的黄尿酸（XA）、犬尿酸（KA）和肌酐。比较了10例非胰岛素依赖型糖尿病患者和10名正常健康受试者的结果。本研究未进行色氨酸负荷试验，因为色氨酸负荷会进一步导致活性维生素B6潜在缺乏，从而使病情加重。糖尿病患者中XA与KA以及与肌酐的比值分别为0.35±0.099（平均值±标准差）和0.99±0.321。正常受试者的相应数值分别为0.17±0.064和0.55±0.22。糖尿病患者的这两个比值均显著高于正常受试者（分别为p＜0.001和p＜0.01）。这意味着糖尿病患者中XA排泄过多，导致色氨酸代谢异常。我们的研究结果表明，这些比值有助于监测XA的过量排泄，也可用于糖尿病的检测。
