In vitro determination of intestinal amino acid (14C-L-glycine) absorption during cholera.

In vitro uptake of 14C-L-glycine was studied in jejunal mucosa biopsy specimens from 27 patients with cholera (proven by stool culture) presenting within 48 h of onset of watery diarrhea. In time series experiments, 14C-L-glycine uptake was found to follow saturation kinetics (being saturated at 5 1/2 min), to be blocked by uncouplers of oxidative phosphorylation (sodium fluoride and 2:4-dinitrophenol), and that 14C-L-glycine uptake by both amino acid transport system 1) and amino acid transport system 4) were active during the active purging stage of cholera. Concentration series experiments were carried out to determine the Vmax and Kt of these transport systems, which were not significantly different. This study demonstrates continued absorption of amino acids (glycine) by two amino acid transport systems, provides scientific basis for use of glycine in "improved" oral rehydration solutions in the treatment of acute diarrhea, and emphasizes the importance of maintaining feeding during acute diarrhea in order to prevent development of malnutrition.