Small intestinal absorption of amino acids and a dipeptide in pancreatic insufficiency.

Abstract

SUMMARY In this study a perfusion technique has been used to investigate in vivo jejunal absorption and transmural potential difference evoked by the neutral amino acids phenylalanine (56 or 20 mmol/l) and glycine (20 mmol/l), the dibasic amino acid lysine (56 or 5 mmol/l), and a dipeptide glycyl-l-phenylalanine (20 mmol/l) in 11 children with pancreatic insufficiency due to cystic fibrosis and in three children with other causes of exocrine pancreatic insufficiency. Net absorption and potential difference evoked by phenylalanine in both cystic fibrosis and pancreatic insufficiency, and net absorption of glycine in cystic fibrosis were significantly reduced; but the absorption of lysine and glycyl-l-phenylalanine was normal. Absorption of the constituent amino acids from the dipeptide was normal or increased in cystic fibrosis. Thus, these studies show a defect in active absorption of neutral amino acids in cystic fibrosis with pancreatic insufficiency and exocrine pancreatic insufficiency. We speculate that pancreatic factors participate in neutral amino acid absorption.

13C-egg white breath test: a non-invasive test of pancreatic trypsin activity in the small intestine

“…The breath test data in this study are in agreement with the generally accepted statement that intraluminal pancreatic digestion is very important in the overall process of protein assimilation 15. Other mechanisms possibly contributing to deficient protein assimilation in pancreatic disease, such as accelerated small intestinal transit or inadequate absorption,27 28 should be kept in mind as well.…”

Comparison of the Safety of Early Enteral vs Parenteral Nutrition in Mild Acute Pancreatitis

“…In both animal and human studies, elemental or semi-elemental small peptide formulas have been shown to be well tolerated and efficiently absorbed in a gut lumenal environment with little or no pancreatic enzyme secretion. [10][11][12][13] Case series have documented that TEN could be used safely as transitional feeding in patients who had peaked and had begun to resolve the inflammatory response associated with pancreatitis. 14-21…”

The Role of the Small Intestine in Cystic Fibrosis Patients

“…Clinically overt vitamin B 12 deficiency, however, is rarely observed in C F patients (20). Reduced uptake of phenylalanine (16,21), cycloleucine (16) and glycine (21) but not of lysine (16) has been shown in C F patients. Finally, pronounced fecal bile acid loss has been documented in C F patients by Weber et al (22).…”