期刊名称：Journal of Nutritional Science and Vitaminology
印刷版ISSN：0301-4800
电子版ISSN：1881-7742
出版年度：1981
卷号：27
期号：4
页码：311-317
DOI：10.3177/jnsv.27.311
出版社：Center for Academic Publications Japan
摘要：Transport of [3H]pyridoxine was studied with membrane vesicles prepared from brush border of guinea pig jejunum, in which pyridoxal kinase was not detected. The imposition of an Na+ gradient across the membrane did not affect pyridoxine transport. The equilibrium level of pyridoxine uptake decreased with increasing osmolarity of the medium, which indicates that pyridoxine is transported into the membrane vesicles. The initial rate of pyridoxine uptake increased linearly with increasing pyridoxine concentration throughout the range of 0.18μM to 7.4μM both in the presence and absence of an Na+ gradient. 4'Deoxypyridoxine and unlabeled pyridoxine, added in excessive amounts, did not inhibit pyridoxine transport into the membrane vesicles. These results substantiate the notion that pyridoxine passes through the brush border membrane by simple diffusion.
