Intestinal Transport of Amino Acids and Glucose in Flounder Fish.

Abstract

Summary Everted intestinal sacs of winter flounders were used in the summer to study the transmucosal movement of glucose and certain aromatic amino acids and derivatives. It was found that glucose was not transported against a concentration gradient. L-tyrosine, D-tyrosine, m-tyrosine, o-tyro-sine, 3-amino-tyrosine, 3,5-dichloro tyrosine and 3,4-dihydroxyphenylalanine were transported from mucosal to serosal side against a concentration gradient. 3,5-dibromo- and 3,5-dinitro-tyrosine were not transported. Among the tryptophan compounds which were studied, only L-tryptophan was transported; D-tryptophan and tryptamine were not transported against a concentration gradient.