The Absorption of Amino Acid Mixtures from the Small Intestine of the Rat

A Survey of the Effect of Other Ammo-acids on the Absorption of L-arginine and L-lysine by the Rat Intestine

“…As usual, arginine inhibits lysine uptake more strongly than vice versa. Table V shows the relative am ounts of several amino-acids absorbed from an equim olar m ixture: as shown previously by Orten [12] and Delhumeau et al [4], arginine and lysine, the two dibasic ainino-acids, are among the most readily absorbed.…”

“…Also the uptake of L-lysine was strongly inhibited by L-arginine whereas the L-lysine had relatively little effect on the absorption of L-arginine. These results go far to explain the findings of Orten [12] and of Delhumeau et al [4], repeated in this laboratory by a different method ( Table V ), th a t when the intestinal mucosa is subjected to an equi molar m ixture of all utilisable amino-acids, the basic amino-acids are among the m ost readily absorbed. Orten [12] found th at L-arginine and L-isoleucinc were absorbed the most strongly and th at L-lysine was not far behind.…”

Leucine and valine requirements of the lactating sow

“…Little evidence could be found for specific competition between leu cine and isoleucine when Delhumeau et al (1962) studied the intestinal absorption of amino acid mixtures, including the branched chain amino acids.…”

In Vitro Studies on Protein Digestion, Amino Acid Absorption Interactions

“…Sheffner et al (9) and Bergen et al (8) reported that the composition of gmino acids mixtures liberated by in vitro proteolysis can differ from the amino acid composition of the proteins; similar differences were obtained with pepsin digestion of proteins in this study. Delhumeau et al (5) suggested that amino acid uptake in the presence of amino acid mixtures liberated by enzymic degradation may differ from amino acid uptake in the presence of amino acid mixtures simulating dietary proteins. In agreement, the present data indicate that histidine or methionine uptake in the presence of pepsin amino acid liberation patterns differ from that with amino acid mixtures simulating the amino acid content of the proteins used.…”

“…Although each amino acid has a characteristic rate of uptake, in the presence of other amino acids uptake rate ( 1 ) and entry site competition within groups of amino acids has been reported (1)(2)(3)(4). Delhumeau et al (5) investigated rates of uptake of amino acids from equimolar amino acid mixtures or amino acid mixtures simulating proteins in the rat. They observed that the percentage uptake from the initial concentration of each amino acid was not changed by different molar ratios but that amino acid mixtures simulating proteins can affect the overall rate of amino acid uptake.…”