The Absorption of Milk-Bound Pteroylglutamic Acid from Small Intestine Segments

Abstract

Binding tritiated pteroylglutam-ic acid to cow or to goat milk protein was associated with a substantial reduction in its absorption from rat jejunum, while the ileal absorption increased markedly. There was no difference in the amount of folate absorbed whether it was bound to cow milk or to goat milk. Despite the fourfold higher folate binding capacity of goat milk than of cow milk, there was no difference in the amount of folate absorbed after their administration. Folate depletion or folate overload had no effect on the amount of the milk-bound folate absorbed, while such treatments decreased the absorption of free folate.