Studies on Fe Complexes Produced by Yeast. IV. : Mechanism of Fe Transport from an Fe(II)-Oligosaccharide Complex across the Mucosal Membrane of the Rat Intestine
スポンサーリンク
概要
- 論文の詳細を見る
The mechanism of Fe transport across the rat duodenal membrane from an Fe(II)-oligosaccharide complex (designated B1-c) produced in wine by yeast and showing high hematopoietic activity in rats was examined. The Fe uptake from B1-c by brush border membrane (BBM) vesicles isolated from the rat intestine was based mainly on the Fe binding to membarne components which were suggested to be inside the vesicles. Evidence that Fe was transported into the vesicles by a special transport system other than simple diffusion was obtained by observing saturation kinetics under conditions of isotope exchange, and temperature and pH dependence. This Fe uptake was not inhibited by any metal ions tested, including inorganic Fe(II), and the BBM vesicles from the duodenum had a higher Fe uptake than those from the other parts of the small intestine. Furthermore, the BBM vesicles isolated from rats with Fe deficiency showed a significantly increased Fe uptake. The K_m value for B1-c uptake was 0.16mM, lower than the values for FeSO_4 and ferrous ascorbate. These results suggest that a special transport system selective for B1-c may be present on the mucosal membrane. B1-c was taken up by the BBM vesicles in the form of Fe-oligosaccharide complex. From the preloaded vesicles, B1-c was released temperature- and pH-dependently. The fractionation of the intestinal mucosa used in in situ and in vitro absorption experiments suggests that the Fe transport across the BBM by a special transport process is the initial step of the intestinal absorption of Fe from B1-c and that Fe is transferred into a soluble fraction of the mucosal cells in the form of a complex with oligosaccharide.
- 公益社団法人日本薬学会の論文
- 1989-02-25
著者
-
田中 健太郎
Faculty Of Technology Yamanashi University
-
田端 滋
Pharma Research Laboratories Hoechst Japan Limited
関連論文
- Studies on Fe Complexes Produced by Yeast. V. : Role of the Ligand in Fe Absorption from an Fe(II)-Oligosaccharide Complex
- Studies on Fe Complexes Produced by Yeast. IV. : Mechanism of Fe Transport from an Fe(II)-Oligosaccharide Complex across the Mucosal Membrane of the Rat Intestine
- Studies on Fe Complexes Produced by Yeast. III. : Characteristics of Fe Absorption from an Fe(II)-Oligosaccharide Complex in the Rat Gastrointestinal Tract
- Studies on Fe Complexes Produced by Yeast. I. Separation of Fe Complexes from Wine and Their Incorporation into Hemoglobin in Rats(Biological)