Effect of fat digestion on superior mesenteric artery blood flow in humans.
OBJECTIVE
Intraluminal nutrients stimulate superior mesenteric artery (SMA) blood flow. Of the macronutrients, especially fat affects the magnitude of the SMA blood flow response to a meal. Little is known however on the influence of fat hydrolysis on SMA flow.


METHODS
We compared in eight healthy volunteers the SMA flow response (Doppler ultrasonography) to continuous intraduodenal fat perfusion (LCT, 240 kCal h(-1)) during conditions with normal hydrolysis (placebo, control), increased hydrolysis (pancreatic enzyme supplementation; 50 kU lipase) and impaired hydrolysis (orlistat 240 mg).


RESULTS
Intraduodenal LCT significantly (P<0.01) increased SMA flow in all experiments over basal. The SMA flow response to fat during pancreatic enzyme supplementation (1.49 +/- 0.1 l min(-1)) was significantly (P<0.05) higher compared with placebo (1.11 +/- 0.16 l min(-1)). Lipase inhibition with orlistat did not significantly affect fat stimulated SMA flow compared with placebo: 0.89 +/- 0.08 l min(-1) versus 1.11 +/- 0.16 l min(-1).


CONCLUSIONS
Administration of pancreatic enzymes significantly increases fat stimulated SMA flow. Fat digest products in the intestinal lumen contribute to the regulation of SMA blood flow.
Symersky
T
T
Department of Gastroenterology-Hepatology, Leiden University Medical Canter, Leiden, The Netherlands.
Huisman
E J
EJ
Wasser
M N J M
MN
Masclee
A A M
AA
D000328:Adult; D001783:Blood Flow Velocity / Q000187:drug effects / Q000502:physiology*; D004041:Dietary Fats / Q000008:administration & dosage* / Q000378:metabolism*; D004063:Digestion / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D017538:Mesenteric Artery, Superior / Q000187:drug effects / Q000502:physiology*; D008875:Middle Aged
D004041:Dietary Fats