Comparative effects of intraduodenal infusions of lauric and oleic acids on antropyloroduodenal motility, plasma cholecystokinin and peptide YY, appetite, and energy intake in healthy men.
BACKGROUND
The regulation of gastrointestinal function and energy intake by fatty acids depends on their chain length. Animal studies suggest that lauric acid (C12) may have more potent suppressive effects on energy intake than does oleic acid (C18).


OBJECTIVE
We compared the effects of equicaloric loads of C12 and C18 on antropyloroduodenal (APD) motility, plasma concentrations of cholecystokinin (CCK) and peptide YY (PYY), appetite, and energy intake.


METHODS
Thirteen healthy men (aged 20-46 y) were studied on 3 occasions in double-blind, randomized fashion. APD pressure waves, plasma hormones, and appetite perceptions were measured during 60-min intraduodenal infusions of 1) C12, 2) C18, or 3) 0.9% saline as control (rate: 4 mL/min; energy load for C12 and C18: 0.4 kcal/min); between 60 and 90 min, the subjects consumed a meal. Energy intake at a buffet meal was quantified.


RESULTS
C12 and C18 both reduced antral (P < 0.001) and duodenal (P < 0.01) pressure waves and stimulated isolated pyloric pressure waves (P < 0.01) and plasma CCK (P < 0.001), with no differences between them. Although C12 and C18 both increased basal pyloric pressure (P < 0.05), C12 had a greater effect than did C18 (P < 0.01). In contrast, although both C12 and C18 increased plasma PYY (P < 0.001), C18 had a greater effect than C12. C12, but not C18, suppressed energy intake (P < 0.05).


CONCLUSIONS
At the load administered, C12, but not C18, suppressed energy intake, and C12 was a more potent stimulant of basal pyloric pressure. These discrepant effects are not apparently accounted for by changes in CCK or PYY secretion.
Feltrin
Kate L
KL
University of Adelaide Discipline of Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia.
Little
Tanya J
TJ
Meyer
James H
JH
Horowitz
Michael
M
Rades
Thomas
T
Wishart
Judith
J
Feinle-Bisset
Christine
C
D000328:Adult; D001066:Appetite / Q000187:drug effects*; D002766:Cholecystokinin / Q000097:blood*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004386:Duodenum / Q000187:drug effects; D002149:Energy Intake / Q000187:drug effects*; D005769:Gastrointestinal Motility; D006801:Humans; D007263:Infusions, Parenteral; D007850:Lauric Acids / Q000737:chemistry / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D009829:Oleic Acids / Q000737:chemistry / Q000494:pharmacology*; D019894:Peptide YY / Q000097:blood*; D011312:Pressure; D011708:Pylorus / Q000187:drug effects
D007850:Lauric Acids; D009829:Oleic Acids; D019894:Peptide YY; D002766:Cholecystokinin