Mizuma T, Awazu S
Department of Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Science (TUPLS), Japan.
Res Commun Mol Pathol Pharmacol. 1998 Apr;100(1):43-52.
Intestinal transport and metabolism of p-nitrophenyl alpha-disaccharides were studied. In the absorption of p-nitrophenyl alpha-melibioside, no compounds other than p-nitrophenyl alpha-melibioside were detected on either the mucosal or the serosal side. In the absorption of p-nitrophenyl alpha-maltoside, on the other hand, p-nitrophenyl alpha-glucoside was formed on the mucosal side to appear on the serosal side. p-Nitrophenol and p-nitrophenyl beta-glucuronide also appeared on the serosal side in the absorption of p-nitrophenyl alpha-maltoside, and the total amount transported to the serosal side was significantly decreased in the absence of Na+ (a cosubstrate of Na+/glucose cotransporter (SGLT1)). Furthermore, the total transport clearance of p-nitrophenyl alpha-glucoside formed from p-nitrophenyl alpha-maltoside on the mucosal side in the p-nitrophenyl alpha-maltoside absorption, was similar to that of the absorption of p-nitrophenyl alpha-glucoside itself. These results led to the conclusion that the intestinal absorption of disaccharide conjugate depended on disaccharidase, and the absorption of the alpha-maltose conjugate occurred sequentially by the maltase-catalyzed hydrolysis of the disaccharide conjugate and SGLT1-mediated transport of the glucose conjugate.
对对硝基苯基α-二糖的肠道转运和代谢进行了研究。在对硝基苯基α-蜜二糖的吸收过程中，在黏膜侧或浆膜侧均未检测到除对硝基苯基α-蜜二糖以外的化合物。另一方面，在对硝基苯基α-麦芽糖苷的吸收过程中，在黏膜侧形成了对硝基苯基α-葡萄糖苷，并出现在浆膜侧。在对硝基苯基α-麦芽糖苷的吸收过程中，对硝基苯酚和对硝基苯基β-葡萄糖醛酸苷也出现在浆膜侧，并且在没有Na +（Na + /葡萄糖共转运体（SGLT1）的共底物）的情况下，转运到浆膜侧的总量显著降低。此外，在对硝基苯基α-麦芽糖苷吸收过程中，在黏膜侧由对硝基苯基α-麦芽糖苷形成的对硝基苯基α-葡萄糖苷的总转运清除率，与对硝基苯基α-葡萄糖苷本身的吸收清除率相似。这些结果得出结论，二糖共轭物的肠道吸收取决于二糖酶，并且α-麦芽糖共轭物的吸收是通过二糖酶催化的二糖共轭物水解和SGLT1介导的葡萄糖共轭物转运依次发生的。
