Hexose inhibition of amino acid uptake in the rat-kidney-cortex slice

Abstract Glucose, galactose and fructose have been shown to inhibit the intracellular accumulation of amino acids by the rat-kidney-cortex slice. The uptake of glycine, α-amino- [1− 14 C]isobutyric acid, valine and cycloleucine was inhibited by these hexoses but the accumulation of lysine, histidine and phenylalanine was unaffected. The inhibitory effect has been shown to be dependent upon the length of incubation and upon the sugar concentration. Evidence has been presented to indicate that sugars reduce the rate of influx of amino acid into cells but have no effect upon the apparent affinity of transport sites for amino acids.