Glucose modulates vitamin C transport in adult human small intestinal brush border membrane vesicles.

@article{Malo2000GlucoseMV,
  title={Glucose modulates vitamin C transport in adult human small intestinal brush border membrane vesicles.},
  author={C. Malo and J. Wilson},
  journal={The Journal of nutrition},
  year={2000},
  volume={130 1},
  pages={
          63-9
        }
}
The uptake of L-ascorbate (vitamin C) and its oxidized form, dehydro-L-ascorbic acid (DHAA), was evaluated in brush border membrane vesicles isolated from adult human duodenum, jejunum and ileum. Ascorbate was taken up along the entire length of the small intestine with a threefold higher initial uptake rate in distal than proximal segments. Ascorbate uptake was Na(+)-dependent, potential-sensitive and saturable (K(m), 200 micromol/L), whereas DHAA transport involved facilitated diffusion (K(m… Expand
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Results suggest that high-dose supplements might not be the most efficient way of increasing the body pool of vitamin C. Expand
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