glucose entry
Last reviewed 01/2018
Unlike the active absorption of glucose into epithelial cells in the gut and kidney, glucose is taken up passively by most cells of the body.
There is evidence that it diffuses across the plasma membrane in association with a protein carrier molecule:
- transport is stereospecific for the D-isomer
- flux of glucose exhibits saturation kinetics
- molecules with a similar structure can compete with glucose for uptake into the cell
The diffusion gradient is maintained by 'fixing' of glucose within the cell as glucose-6-phosphate; the latter is incapable of transmembranous movement.