The proximal convoluted tubule of the thyroparathyroidectomized rat was perfused in vivo to examine the effects of D-glucose on phosphate absorption. The addition of 5.6 mM D-glucose to the perfusion solution resulted in a significantly lower tubular maximum for phosphate of 6.2±0.5 pmol/min/mm as compared to 12.0±0.7 pmol/min/mm when no glucose was present (p<0.001). 10-4 M phloridzin had no significant effect on phosphate transport, and when both D-glucose and phloridzin were added to the perfusion solution, phosphate absorption averaged 10.6±0.6 pmol/min/mm, a value not significantly different from that obtained with the perfusion solution containing no D-glucose. These findings indicate that D-glucose in the lumen of the proximal tubule inhibits phosphate absorption. This effect of D-glucose on phosphate transport requires the transport of the D-glucose but does not appear to be due to an interaction of the two substances at the luminal surface of the proximal tubular cells.
|Original language||English (US)|
|Number of pages||6|
|Journal||Mineral and Electrolyte Metabolism|
|State||Published - 1980|
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism