Plasma 1,5-anhydroglucitol level as a marker of glycemic control in diabetes mellitus.

1，5-脱水葡萄糖醇（AG）是一种六碳单糖，其结构类似于葡萄糖，是人体血清中的主要多元醇之一。血中低浓度的银已被证明与糖尿病有关，但由于测量方法的困难，对其代谢和动力学知之甚少。本研究表明，大鼠血浆AG的降低主要是由于尿AG排泄加快，与葡萄糖排泄同步。另一方面，根据测定方法的改革，我们测定了大量的人体样品，阐明了血浆AG的动力学，血浆AG的降低程度与尿AG排泄量有很好的相关性，后者反映了尿葡萄糖排泄量，而与引起糖尿的药物种类无关。我们还证明，尽管AG在体内的分布是全方位的，但其摄取和催化并不是很活跃。肾小管对AG的重吸收受葡萄糖的抑制。因此，血浆AG的降低似乎密切反映了糖尿的程度。在人体研究中，我们证实了血浆AG浓度在糖尿病中显示出特异性降低。血浆AG水平受内分泌功能、肝肾功能、体质量、性别、年龄等因素的影响较小。本文讨论了血浆AG测定的临床意义。

1,5-Anhydroglucitol(AG) is a six-carbon monosaccharide with a structure resembling that of glucose, and one of the main polyols in human serum. A low ag concentration in blood has been shown to be associated with diabetes mellitus.However, little has been known about its metabolism and kinetics partially because of the difficulties in methods of measurement. In this study, we demonstrated that the reduction of plasma AG is mainly due to the accelerated urinary excretion of AG which is coincident with the excretion of glucose in rats. On the other hand, according to the reform of assay methods, we have measured a lot of human samples and elucidated the kinetics of plasma AG.The degree of the reduction of plasma AG was well correlated with the amount of urinary excretion of AG, and the latter reflected the amount of urinary excretion of glucose irrespective of the kind of agent causing the glucosuria in rats. We also demonstrated that the uptake and catabolism of AG were not very active despite of its all-around distribution in the body. The reabsorption of AG was inhibited by glucose in renal tubule. Thus, the reduction of plasma AG seemed to reflect closely the extent of the glucosuria. In human study, we confirmed that the concentration of plasma AG showed a specific reduction in diabetes mellitus. The level of plasma AG was little affected by various factors, such as endocrine function, liver dysfunction, renal dysfunction, body mass, sex or age. The clinical significance of measurement of plasma AG are discussed in this report.