Dipeptide Absorption in Cystinuria

Dipeptide absorption in man.

A quantitative perfusion method has been used to study intestinal absorption of two dipeptides-glycyl-glycine and glycyl-l-alanine-in normal subjects. In each case, the constituent amino acids were absorbed faster when presented as dipeptides than as free amino acids, suggesting intact dipeptide transport. During absorption constituent amino acids were measured within the lumen and it is sugges...

Intestinal absorption of an arginine-containing peptide in cystinuria.

Separate tolerance tests involving oral intake of the dipeptide, L-arginyl-L-aspartate, and of a corresponding free amino acid mixture, were carried out in a single type 2 cystinuric patient. Absorption of aspartate was within normal limits, whilst that of arginine was normal after the peptide but considerably reduced after the amino acid mixture. The results are compared with the increments of...

Glucose-dependent insulinotropic polypeptide regulates dipeptide absorption in mouse jejunum.

Glucose-dependent insulinotropic polypeptide (GIP) secreted from jejunal mucosal K cells augments insulin secretion and plays a critical role in the pathogenesis of obesity and Type 2 diabetes mellitus. In recent studies, we have shown GIP directly activates Na-glucose cotransporter-1 (SGLT1) and enhances glucose absorption in mouse jejunum. It is not known whether GIP would also regulate other...

Intestinal absorption of cystine and cysteine in normal human subjects and patients with cystinuria.

1. An intestinal perfusion technique has been used to study absorption in uivo of L-cystine and L-cysteine in six normal human subjects and three patients with homozygous cystinuria. 2. No significant absorption of L-cystine was detected during perfusion of the cystinuric patients, whereas L-cysteine absorption was normal. These results imply that L-cystine and L-cysteine are normally absorbed ...

Cystinuria and renal transplantation.