EFFECTS OF LYSINE, PHENYLALANINE, TYROSINE, AND VALINE ON THE KINETICS OF ZINC ABSORPTION IN ILEUM OF RAT / 营养学报

ABSTRACT

The results of lysine, phenylalanine, tyrosine, and valine on kinetics of zinc absorption in rat ileurn using a two-compartment in situ perfusion model showed; 1. Phenylalanine can increase the zinc absorption micro-constants K21, K12, and K02, That is to say phenylalanine increases the a-mount of zinc from lumen to mucosa, from mucosa to lumen, and from mu-cosa to blood. Tyrosine and valine can increase the values of K21, so more zinc flows from lumen to mucosa; 2. The results of amino acids on the half times of zinc absorption showed that phenylalanine decreases both the half times of the fast phase and the slow phase, while valine decreases only the half time of the fast phase. Lysine and tyrosine have no effects on the half times of zinc absorption. The results of this study indicate that phenylalanine, tyrosine, and valine increase zinc absorption in the ileum of rat. The enhancing effects of amino acids on zinc absorption are related to the stability constants of zinc-amino acid chelators.