Glutamate (GLU) is the major excitatory neurotransmitter in the body. GLU receptors and transporters are present in the gut. Emerging evidence suggests that GLU may play a functional role in promoting gastric emptying and digestion. We hypothesized that dietary GLU stimulates gastric emptying in the developing gut. 10‐d preterm, parenterally‐fed pigs received partial enteral nutrition (25%) as milk‐based formula supplemented with monosodium glutamate (MSG) at 0, 2, 4 and 6 times the basal GLU intake (n=5–8 pigs/group) for 7 d. Calorimetry and 13C‐octanoic acid breath test were performed on d 3, 5, 7 and 9 of life. We found no differences in body weight gain, organ weight and arterial plasma GLU and glutamine concentrations between the treatment groups. However, portal GLU concentration was significantly higher in pigs fed the MSG 4 and 6 doses. There was no treatment effect on VO2 uptake, VCO2 production, respiratory exchange ratio and heat production. The average lag time (Tlag) and gastric half emptying time (T1/2) between all treatment groups were 121 and 188 min, respectively. Tlag and T1/2 tended to increase with MSG supplementation in a dose dependent manner. At d 9, the cumulative % recovery of 13C‐octanoic acid was lower in MSG‐4 and MSG‐6 groups. Our results suggest that enteral MSG supplementation slows gastric emptying in the developing gut. (Funded by Ajinomoto)
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