Possible Interaction: Glutamine and Phenylalanine

“ Glutamine entry at 0.06 mM was inhibited by a variety of amino acids at 3 mM, including dibasic amino acids, glycine, valine, and phenylalanine.”

“A 20-fold excess of unlabeled leucine, isoleucine, methionine, valine, alanine, lysine, histidine, phenylalanine, and glutamine inhibited uptake of leucine and phenylalanine , and six of these amino acids inhibited uptake of alanine, by more than 50% both in the presence and absence of a potassium ion gradient.”

“Transport of glutamine (5 microM) was inhibited by asparagine, histidine, alanine, serine, and phenylalanine at 1 mM (25-74%), but leucine and N-methylaminoisobutyric acid (MeAIB) did not significantly inhibit glutamine uptake.”

“ L-Phenylalanine was used to inhibit glutamine loss , and hippurate was used to stimulate gamma-GT activity; therefore luminal glutamine conversion to glutamate was promoted.”

“ Phenylalanine and leucine production rates were enhanced with either glutamine or glutamate in rhatannin-treated rats.”

“Abstract: … of L‐glutamine (2 mM) by rat brain cortex slices against a concentration gradient is markedly inhibited (40%) by branched‐chain Lamino acids (1 mM), L‐phenylalanine (1 mM), or L‐methionine (1 mM); that of L‐asparagine (2 mM) is much less affected by these amino acids.”

“Renal release of Phe the during perfusion with L-PL was 3.0 times control (P less than 0.001) and increased 2.5-fold with addition of glutamine (P less than 0.001); with phenylpyruvate (PP), it was 3.5 times control (P less than 0.001).”

“Cysteine, leucine, valine, methionine, isoleucine, tyrosine, lysine, and phenylalanine increased the rate of glutamine synthesis.”

“Conclusions Intraduodenal infusions of L-Phe and L-Gln , in doses of 0.15 kcal/min and 0.45 kcal/min for 90 minutes, have different effects on antropyloroduodenal motility and CCK in normal-weight men.”

“Positively charged or δ(+) amino groups of lysine, arginine, asparagine, glutamine and histidine are preferentially located within 6 Å of the ring centroids of phenylalanine , tyrosine and trytophan, where they make van der Waals' contact with the δ(−) π‐electrons and avoid the δ(+) ring edge.”