Inhibition of D-galactose transport across the small intestine of rabbit by zinc.

Zinc is an essential trace element necessary to life. Many metallo-enzymes involved in the metabolism of carbohydrates, lipids, proteins, and nucleic acids require zinc for their functions. The aim of this study was to characterize how zinc acts on the intestinal sugar absorption in rabbit. Results obtained show that zinc decreases both D-galactose accumulation in the jejunum tissue, and mucosal to serosal transepithelial flux of this sugar, in a dose-dependent way. Furthermore, zinc seems not to modify sugar diffusion across the intestinal epithelium. The inhibition of intestinal sugar transport by zinc seems to be of a competitive type and it is reversed in high proportion with dithioerythritol (thiol groups protector). The results suggest that zinc decreases carrier-mediated intestinal sugar absorption.