Intraduodenal Free Fatty Acids Rather than Triglycerides Are Responsible for the Release of CCK in Humans

Abstract

Exocrine pancreas from different species behaves differently in response to the presence of intact or digested nutrients in the duodenum. A failure of cholecystokinin (CCK) release after a meal has been shown among patients with exocrine pancreatic insufficiency. This abnormality could be restored by the administration of pancreatic extracts, suggesting that digested rather than intact nutrients are responsible for the release of CCK and subsequently gallbladder contraction in humans. The aim of this study was to determine the specific role of different lipidic stimuli in humans. Seven male patients (mean age, 52 years) with pancreatic insufficiency secondary to chronic pancreatitis were selected. Pancreatic insufficiency was considered severe in five of them (lipase output, <1,000 IU/ min) and moderate in another two (lipase output, >1,000 and <2,300 IU/min). Plasma CCK (by bioassay), gallbladder contraction (by ultrasound), and enzyme output (chymotrypsin) in response to duodenal administration of either oleic acid as free fatty acids or 20% Intralipid as triglycerides were measured in each patient with at least a 48-h interval between each test. In all these patients with pancreatic insufficiency, duodenal perfusion of free fatty acids generated a more pronounced (9 1 ? 1 1 vs. 49 ? 21 pM) and faster (15 vs. 30 min) ( p < 0.05) CCK release than triglycerides. Furthermore, gallbladder contraction was more efficient when free fatty acids instead of triglycerides were administered in the duodenum (86 t 5 vs. 69 * 4%) at 10 min (p < 0.05) and (73 & 8 vs. 5 1 ? 5 % ) at 15 min 0, < 0.03).

Role of Free Fatty Acids in Regulating Gastric Emptying and Gallbladder Contraction

“…Most human studies, which have demonstrated an effect of ID lipid on CCK release, have used triglyceride emulsions, but recent work has clearly established that free fatty acids, rather than triglycerides, stimulate CCK secretion [10, 11]. In patients with pancreatic lipase insufficiency, the CCK response is reduced to triglycerides, but normal to oleic acid [10]; along the same line, administration of a lipase inhibitor [11] or application of non-absorbable fat in the form of polyester sucrose [12] prevents CCK release.…”

“…In patients with pancreatic lipase insufficiency, the CCK response is reduced to triglycerides, but normal to oleic acid [10]; along the same line, administration of a lipase inhibitor [11] or application of non-absorbable fat in the form of polyester sucrose [12] prevents CCK release.…”

Fatty acids stimulate cholecystokinin secretion via an acyl chain length‐specific, Ca2+‐dependent mechanism in the enteroendocrine cell line STC‐1

“…While there are trypsin-sensitive CCK-releasing peptides which may mediate the effect of dietary protein (Liddle, 1995), the precise mechanism for lipids is unknown. Dietary lipids stimulate CCK secretion specifically via intraduodenal free fatty acids (Beardshall et al 1989;Guimbaud et al 1997). Although it is known that long chain triglycerides but not medium chain triglycerides stimulate release of CCK in humans (Isaacs et al 1987), the precise structural specificity of the CCK response to luminal fatty acids has not been characterized.…”

Evaluation of dietary fat sources on growth performance, excreta microbiology and noxious gas emissions in Ross broilers

“…The degree of unsaturation of the dietary fat can influence the secretion and function of hormones and enzymes (Shall et al, 1989;Guimbaud et al, 1997), and digestibility (Zollitsch et al, 1997). Therefore, growth hormones might be linked with the dietary fat and fatty acids in case of broilers.…”