Postprandial mesenteric blood flow in humans: relationship to endogenous gastrointestinal hormone secretion and energy content of food.
OBJECTIVE
To examine the relationship between postprandial superior mesenteric arterial blood flow (SMABF) and endogenous gastrointestinal hormone secretion after liquid meals of varying energy content.


METHODS
Six healthy volunteers received four isovolumetric meals of differing energy content. SMABF was measured before and for 120 min after feeding using duplex ultrasound; plasma levels of gastrointestinal hormones and noradrenaline were measured.


RESULTS
Results are given as means +/- SEM. Postprandial SMABF increased after each meal; the peak mean percentage increment occurred at 28 +/- 8 min, varying from 106 +/- 26% (P < 0.05) with the 800 kj meal to 240 +/- 62% (P < 0.05) with the 4800 kj meal. The rise was sustained and correlated with energy content (r = 0.969; P = 0.031). The subjects' pulse rate increased after each meal and the increment appeared to be related to meal size (r = 0.990; P = 0.008). Blood pressure did not change. The postprandial concentration of N-terminal neurotensin peaked between 30 and 120 min. The mean peak concentration increased from a baseline value of 30.9 +/- 3.5 ng/l by 19.3 ng/l after 800 kj, 31 ng/l after 1600 kj, 38 ng/l after 2400 kj and 64.3 ng/l after the 4800 kj meal (all differences P < 0.05). The rise was sustained and correlated with energy content (r = 0.967; P = 0.033). Plasma noradrenaline concentration also increased significantly after each meal and was related to energy content (r = 0.90; P = 0.036). Plasma insulin concentration showed a similar postprandial response but had no relationship to energy content. Gastrin concentration increased transiently but changes in the concentration of glucagon, vasoactive intestinal polypeptide and neurokinin A were not significant.


CONCLUSIONS
The results indicate a relationship between meal energy content, postprandial SMABF and pulse rate increments. Postprandial increases in N-terminal neurotensin and noradrenaline concentration were also related to energy content and may indicate a role for these hormones in the control of SMABF after feeding.
Parker
D R
DR
Department of Medicine, Bristol Royal Infirmary, UK.
Carlisle
K
K
Cowan
F J
FJ
Corrall
R J
RJ
Read
A E
AE
D000328:Adult; D001794:Blood Pressure; D004435:Eating; D002149:Energy Intake; D005260:Female; D005504:Food Analysis; D005755:Gastrins / Q000097:blood; D005768:Gastrointestinal Hormones / Q000097:blood / Q000378:metabolism*; D005934:Glucagon / Q000097:blood; D006339:Heart Rate; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D015288:Neurokinin A / Q000097:blood; D009496:Neurotensin / Q000097:blood; D009638:Norepinephrine / Q000097:blood; D011674:Pulse; D013152:Splanchnic Circulation; D013997:Time Factors; D018616:Ultrasonography, Doppler, Duplex; D014660:Vasoactive Intestinal Peptide / Q000097:blood
D005755:Gastrins; D005768:Gastrointestinal Hormones; D007328:Insulin; D014660:Vasoactive Intestinal Peptide; D009496:Neurotensin; D015288:Neurokinin A; D005934:Glucagon; D009638:Norepinephrine