INHIBITION OF GASTRIN-STIMULATED GASTRIC-ACID SECRETION BY MEDIUM-CHAIN TRIGLYCERIDES AND LONG-CHAIN TRIGLYCERIDES IN HEALTHY-YOUNG MEN

Long-chain triglycerides inhibit gastric acid secretion, but the effec t of medium-chain triglycerides in humans is unknown. We compared the effects of intraduodenally perfused saline, medium-chain and long-chai n triglycerides on gastrin-stimulated gastric acid secretion and chole cystokinin release. Eight healthy male volunteers participated in this study, Gastrin-stimulated gastric acid output was 9.4 +/- 1.1 mmol/30 min during saline perfusion. It was suppressed by medium-chain trigly cerides by 43 +/- 9% (P = 0.04 vs. saline) and by long-chain triglycer ides by 74 +/- 6% (P = 0.0003 vs. saline), Thus medium-chain triglycer ides inhibited gastrin-stimulated gastric acid secretion but less so t han long-chain triglycerides. When compared to saline perfusion (73 +/ - 6 pM x 30 min) integrated plasma cholecystokinin concentrations were significantly elevated by long-chain triglycerides (96 +/- 5 pM x 30 min, P < 0.004) but not by medium-chain triglycerides perfusion (65 +/ - 7 pM x 30 min). We also investigated the role of cholecystokinin inf usion on gastrin stimulated gastric acid secretion. Higher concentrati ons (191.4 +/- 4.5 pM x 30 min) of CCK than released in the long-chain triglycerides perfusion experiment, did not suppress gastric acid sec retion. Thus, circulating cholecystokinin appears not responsible for the inhibition of gastrin-stimulated gastric acid secretion by dietary fat.