Using a double-lumen tube jejunal perfusion system in vivo, the mutual effects of carnosine (beta-alanyl-L-histidine) and glycylglycine on their respective absorption rates have been studied in six Zambian African adults. Data on the effect of the constituent amino-acids of carnosine on glycylglycine absorption rate have similarly been obtained. The solutions infused in each subject contained (...

I . Rates of absorption of glycine and glycylglycine from a 300 mm jejunal segment were compared in vivo when those compounds were given alone or together to six Zambian African subjects who had no clinical evidence of malnutrition or of gastro-intestinal disease. Solutions containing (A) glycine (~oommol/l), (B) glycine (Ioommol/l)+glycylglycine (50 mmol/l), and (C) glycglglycinc (50 mmolil) w...

The properties of glycylglycine and glycine transport across the mucosal border of the epithelium were studied in isolated guinea pig ileum. The initial influxes of both substances obeyed simple Michaelis-Menten kinetics, but the values of the kinetic parameters were greatly different between two substances; Jmax and Kt for glycine were 290 nmol.cm-2.min-1 and 27 mM, and those for glycylglycine...

The activities of jejunal mucosal peptide hydrolases for glycylglycine, glycyl-L-leucine and L-leucylglycine, were assayed in 37 patients. Eight patients, four of whom had Crohn's disease, were found to have a marked reduction in the activity of glycylglycine dipeptidase and, to a lesser extent, of the other two hydrolases. Although absorption of glycine in the two groups was similar, there was...

1. Sham-operated and bilaterally nephrectomized rats were injected intravenously with glycyl-L-leucine, glycylglycine and glycylsarcosine, and the concentrations of these dipeptides in plasma and muscle, liver, renal cortex (in the sham-operated rats) and intestinal mucosa at various intervals were determined. 2. Initially the plasma concentrations of glycyl-leucine and glycylglycine were highe...

In this research some mathematical calculations has been explained on the “ +VO2 +glycylglycine” system and some equations has been deduced to determine the stability constants ofthe equilibrium models including MLH+, ML and ML2H species (while M+ ≡ +2 VO , H2L+ ≡protonated glycylglycine and MLH+, ML and ML2H represent the considered complexes). Thecalculations are based on some relations betwe...

in this research some mathematical calculations has been explained on the “ +vo2 +glycylglycine” system and some equations has been deduced to determine the stability constants ofthe equilibrium models including mlh+, ml and ml2h species (while m+ ≡ +2 vo , h2l+ ≡protonated glycylglycine and mlh+, ml and ml2h represent the considered complexes). thecalculations are based on some relations betwe...

Gamma-glutamyltransferase activity in serum is shown to be competitively inhibited by the two substrates gamma-glutamyl-4-nitroanilide and glycylglycine. Awareness of this is of importance when one is choosing final reaction conditions for the assay of the enzyme. Gamma-glutamyltransferase probably acts by a "ping-pong bi-bi" kinetic mechanism, which fits with the double competitive substrate i...

The activities of jejunal mucosal peptide hydrolases for glycylglycine, glycyl-L-leucine and L-leucylglycine, were assayed in 37 patients. Eight patients, four of whom had Crohn's disease, were found to have a marked reduction in the activity of glycylglycine dipeptidase and, to a lesser extent, of the other two hydrolases. Although absorption of glycine in the two groups was similar, there was...

A 30 cm segment of the duodenum, jejunum, or ileum of normal human volunteers was perfused, on separate occasions, with test solutions containing either glycylglycine, free glycine, glycylleucine, or equimolar amounts of free glycine and free leucine. Luminal fluid contained no hydrolytic activity against glycylglycine and minimal activity against glycylleucine. In each intestinal segment, amin...