title: Amino acid absorption after intestinal bypass procedures.
abstract: A review of some investigations about amino acid absorption before and after intestinal bypass operations for obesity is presented. One common complication following the operation is hepatic damage. Several studies report a relationship between protein malnutrition and liver dysfunction. Hence, determination of amino acid (and peptide) absorption is of particular importance in order to improve our understanding of this complication. A constant finding in several investigations is the postoperative reduction in plasma concentrations and absorption of branched chain amino acids (leucine, isoleucine and valine). However, the absorption of dipeptides containing the branched chain amino acids does not seem to be affected to the same extent. The changes in the uptake of the branched chain amino acids before and after intestinal bypass operation are correlated with the plasma levels of two proteins with a known sensitivity to protein depletion (thyroxine-binding pre-albumin and retinol-binding protein). Plasma concentrations of some amino acids increases following the operation but there is no evidence so far that this could cause any damage to the liver. The significance of the impaired uptake of the branched chain amino acids is discussed.
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D001798:Blood Proteins / Q000378:metabolism; D005215:Fasting; D006801:Humans; D007082:Ileum / Q000601:surgery*; D007408:Intestinal Absorption; D007583:Jejunum / Q000601:surgery*; D008099:Liver / Q000378:metabolism; D009765:Obesity / Q000628:therapy*; D011183:Postoperative Complications / Q000378:metabolism
chemical_list: D000596:Amino Acids; D001798:Blood Proteins