Methods: In the present study, we have investigated the effects of intraduodenal perfusion of long-chain and medium-chain triglycerides and of sucrose polyester on the release of peptide YY in healthy men.
Results: Perfusion of medium-chain triglycerides (180 mmol fatty acids) increased the plasma concentration of peptide YY from 7.9 pmol L(-1) (SEM 0.2, n=8) to 10.7 pmol L(-1) (SEM 0.5, n=8), whereas perfusion of long-chain triglycerides (180 mmol fatty acids) had a significantly greater effect, increasing peptide YY concentration from 8 6 pmol L(-1) (SEM 0.2, n=8) to 18.9 pmol L(-1) (SEM 2.4, n=8, P < 0.008). A smaller quantity of long-chain triglycerides (90 mmol fatty acids) increased plasma concentration of peptide YY from 7.4 pmol L(-1) (SEM 0.4, n=8) to 13.3 pmol L(-1) (SEM 1.5, n=8), whereas sucrose polyester (90 mmol fatty acids) did not change peptide YY concentration. In a previous study, we investigated gastrin-stimulated gastric acid output in response to these treatments. The correlation between increases in peptide YY in response to all treatments and the decrease in acid output was r=0.72 (n=48, P < 0.0001). These results show that both long-chain and medium-chain triglycerides, but not sucrose polyester, stimulate the release of peptide YY.
Conclusion: We speculate that peptide YY may play an important role in the inhibition of gastrin-stimulated gastric acid secretion by long-chain and medium-chain triglycerides.