J Neurogastroenterol Motil.  2017 Jul;23(3):400-408. 10.5056/jnm16153.

Correlation Between Gastric Emptying and Gastric Adaptive Relaxation Influenced by Amino Acids

• Uchida M
• Kobayashi
• Saito C

• KMID: 2387831
• DOI: http://doi.org/10.5056/jnm16153

Abstract

BACKGROUND/AIMS
Amino acids have many physiological activities. We report the correlation between gastric emptying and gastric adaptive relaxation using tryptophan and amino acids with a straight alkyl chain, hydroxylated chain, and branched chain. Here we sought to further clarify the correlation between gastric emptying and gastric adaptive relaxation by using other amino acids.
METHODS
In Sprague-Dawley rats, gastric emptying was evaluated by a breath test using [1-¹³C] acetic acid. The expired ¹³COâ‚‚ pattern, T(max), C(max), and AUC(120min) values were used as evaluation items. Gastric adaptive relaxation was evaluated in a barostat experiment. Individual amino acids (1 g/kg) were administered orally 30 minutes before each breath test or barostat test.
RESULTS
L-phenylalanine and L-tyrosine did not influence gastric emptying. All other amino acids, ie, L-proline, L-histidine, L-cysteine, L-methionine, L-aspartic acid, L-glutamic acid, L-asparagine, L-arginine, L-glutamine, and L-lysine significantly delayed and inhibited gastric emptying. L-Cysteine and L-aspartic acid significantly enhanced and L-methionine and L-glutamine significantly inhibited gastric adaptive relaxation. L-Phenylalanine moved the balloon toward the antrum, suggesting strong contraction of the fundus. T(max) showed a significant positive correlation (r = 0.709), and C(max) and AUC(120min) each showed negative correlations (r = 0.613 and 0.667, respectively) with gastric adaptive relaxation.
CONCLUSION
From the above findings, it was found that a close correlation exists between gastric emptying and adaptive relaxation, suggesting that enhanced gastric adaptive relaxation inhibits gastric emptying.

Keyword

Amino acids; Aspartic acid; Gastric emptying; Phenylalanine; Rats

MeSH Terms

Acetic Acid
Amino Acids*
Animals
Arginine
Asparagine
Aspartic Acid
Breath Tests
Cysteine
Gastric Emptying*
Glutamic Acid
Glutamine
Histidine
Lysine
Methionine
Phenylalanine
Proline
Rats
Rats, Sprague-Dawley
Relaxation*
Tryptophan
Tyrosine
Acetic Acid
Amino Acids
Arginine
Asparagine
Aspartic Acid
Cysteine
Glutamic Acid
Glutamine
Histidine
Lysine
Methionine
Phenylalanine
Proline
Tryptophan
Tyrosine