Stimulation of L-tryptophan transport by di- and polysaccharides in the small intestine of chicks.
In in vivo and in vitro experiments the effect of various carbohydrates on the absorption of L-tryptophan in the chick small intestine was investigated. On feeding the chicks with semisynthetic diet containing 58.5% of carbohydrates a stimulatory effect of glucose, particularly of starch and saccharose, on the entry of L-tryptophan into the portal vein from the chick gastrointestinal tract has been found. Using an in vitro technique the activating effect of starch and disaccharides (maltose, saccharose) on the intestinal transport of L-tryptophan was detected while monosaccharides (glucose, fructose) at different concentrations had no effect on this process or inhibited it. The possibility that energy of disaccharide hydrolysis is used to stimulate transport process is discussed.
D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D002645:Chickens; D004187:Disaccharides / Q000494:pharmacology*; D005632:Fructose / Q000494:pharmacology; D005947:Glucose / Q000494:pharmacology; D007421:Intestine, Small / Q000187:drug effects / Q000378:metabolism*; D008320:Maltose / Q000494:pharmacology; D011134:Polysaccharides / Q000494:pharmacology*; D013213:Starch / Q000494:pharmacology; D014364:Tryptophan / Q000378:metabolism*
D004187:Disaccharides; D011134:Polysaccharides; D005632:Fructose; D008320:Maltose; D014364:Tryptophan; D013213:Starch; D005947:Glucose