Intestinal absorption of galactose as a function of the concentration of NA+

Abstract
A study was made, using the Sois and Ponz successive-absorption technique, of the influence of the sodium ion on the transport of D-galactose through the intestine in situ of the rat. On each animal four succesive absorptions, of 15 minutes duration, were carried out, with a 2.77 mM solution of D-galactose. In the first absorption the sugar solution contained 154 meq/1 of Na+, while in the other three absorptions the concentration of Na+ was varied (154 — 0 mea/1) which was substituted for isotonia with the necessary quantity of sorbitol.
With 154 meq/1 of Na+ in four successive periods, the intestinal absorption of D-galactose remains constant. On substituting the sorbitol for the Na+, the absorption is proportionally reduced. The inhibition is already appreciated on passing to 12'0 meq/1 of Na+, and it reaches 75 % in the initial absence of Na+.