Malone J I, Lowitt S
Department of Pediatrics, University of South Florida College of Medicine, Tampa.
Metabolism. 1992 Feb;41(2):224-7. doi: 10.1016/0026-0495(92)90157-6.
Two methods are commonly used to measure sorbitol in mammalian tissues. The first uses sorbitol dehydrogenase for a coupled enzymatic reaction; unfortunately, other polyols are also substrates for this enzyme. The second uses gas-liquid chromatography (GLC) for separation of polyols and mass quantitation of sorbitol. A comparison of these two methods for the measurement of sorbitol in duplicate samples of lens, nerve, and erythrocytes indicates that GLC of polyol acetates consistently finds less sorbitol than measured by sorbitol dehydrogenase. Erythritol, threitol, ribitol, arabitol, and galactitol are polyols found in variable quantities in these tissues, which have a variable influence on the activity of sorbitol dehydrogenase and therefore alter sorbitol quantitation with this enzyme. Moreover, there is an unidentified substance(s) that reacts with sorbitol dehydrogenase which seems to increase in association with hyperglycemia in the lens and nerve, but not in erythrocytes. The quantity of this unknown substance(s) seems to be reduced by the aldose reductase inhibitor sorbinil in erythrocytes and to a lesser extent sciatic nerve and lens. Since enzymatic sorbitol quantitation in the lens, nerve, and erythrocytes is influenced by many known and unknown factors other than sorbitol, we recommend that GLC of polyol acetates be used to measure sorbitol in biologic tissues.
测量哺乳动物组织中山梨醇的常用方法有两种。第一种方法使用山梨醇脱氢酶进行偶联酶促反应；遗憾的是，其他多元醇也是该酶的底物。第二种方法使用气液色谱法（GLC）分离多元醇并对山梨醇进行质量定量。对晶状体、神经和红细胞的重复样本进行山梨醇测量的这两种方法的比较表明，多元醇乙酸酯的气液色谱法始终比山梨醇脱氢酶法测得的山梨醇含量少。赤藓醇、苏糖醇、核糖醇、阿拉伯糖醇和半乳糖醇是这些组织中含量各异的多元醇，它们对山梨醇脱氢酶的活性有不同影响，因此会改变用该酶进行的山梨醇定量。此外，有一种未知物质与山梨醇脱氢酶发生反应，在晶状体和神经中，这种物质似乎与高血糖相关而增加，但在红细胞中并非如此。红细胞中的醛糖还原酶抑制剂索比尼尔似乎能减少这种未知物质的量，坐骨神经和晶状体中的减少程度较小。由于晶状体、神经和红细胞中的酶促山梨醇定量受到除山梨醇之外的许多已知和未知因素的影响，我们建议使用多元醇乙酸酯的气液色谱法来测量生物组织中的山梨醇。
