Nutrient absorption and malabsorption

Abstract

Interesting new data was generated during the past year with respect to lipid metabolism, molecular biology, polyamine metabolism, bile salt absorption, electrolytes, and peptide and amino acid absorption in the intestine. The chylomicron remnants were shown to be taken up by enteroyctes in a receptor-dependent manner. An apolipoprotein B knockout mouse in which a human apolipoprotein B100 transgene was inserted was produced in which the liver but not the intestine expressed apolipoprotein B, resulting in impaired lipid export from the intestine. The homeobox gene, cdx-2, was shown to be important in cellular differentiation. The ontogeny of the sodium-dependent bile acid transporter was described. GLUT-5 was shown to be regulated in part by substrate load. Site-directed mutagenic studies identified the active site of lactase.