TY - JOUR
T1 - The provision of phosphorylatable substrate during hypoxia decreases jejunal harrier
AU - Tappenden, Function K A
AU - Russell, D. H.
AU - Chen, C. Y.
AU - Noyes, C. T.
AU - Weisbrodt, N. W.
PY - 1998
Y1 - 1998
N2 - There is an emerging consensus that the provision of early enterul nutrition benefits ':he high-risk surgical patient. However, in patients with inadequate gastrointestinal perfusion the presence of food in the intestine may increase the oxygen demand beyond that which can be satisfied by the available delivery, potentially leading to intestinal malfunction. The objective of this study was to determine the effect of metabolic substrate on gastrointestinal function during various oxygénation states. Jejunal samples, obtained from 32 male SpragueDawley rats (263il5g) were stripped of the muscularis, mounted in an I Issing chamber and randomized to be incubated in media equilibrated with 1 of 4 gas mixtures (95%, 75%, 50% and 25% oxygen). Following a 30 minute equilibration, fluorescent probes (4,000 and 17,000 MW) were added to the incubation media on the mucosal side. The rate of probe accumulation on the serosal side was determined before and after the addition of 1 of 4 substrates to the mucosal media: mannitol (an osmotic control), glucose (which is transported, phosphorylated, and metabolized), 2-dcoxyglucose (a glucose analog which is transported and phosphorylated hut not metabolized) or 3-o-methylglucose (a glucose analog which is transported but not phosphorylated or metabolized). In the 95%, 75% and 50% oxygen groups, glucose and 2-deoxyglucose increased (p<'0.05j the permeation rate of the 17,000 MW probe whereas mannitol and 3-omethylglucose did not. Glucose and 2-deoxyglucose also increased (p<0.05) the permeation rate of the 4,000 MW probe in the 95% and 75% groups, but mannitol and 3-o-methylglucose did nol. The effect of the glucose and 2-deoxyglucose on the permeation rate of both probes was more pronounced (p<0.()5) the lower the oxygénation level. These initial results suggest that the provision of solutes that are subject to phosphorylation may exacerbate the loss of gastrointestinal barrier function found during hypoxia. Although the early provision of nutrients is an important intervention in acutely injured patients, care must be taken to ensure that gaslrointestinal perfusion is adequate to allow substrate metabolism and prevent further compromise in gastrointestinal function.
AB - There is an emerging consensus that the provision of early enterul nutrition benefits ':he high-risk surgical patient. However, in patients with inadequate gastrointestinal perfusion the presence of food in the intestine may increase the oxygen demand beyond that which can be satisfied by the available delivery, potentially leading to intestinal malfunction. The objective of this study was to determine the effect of metabolic substrate on gastrointestinal function during various oxygénation states. Jejunal samples, obtained from 32 male SpragueDawley rats (263il5g) were stripped of the muscularis, mounted in an I Issing chamber and randomized to be incubated in media equilibrated with 1 of 4 gas mixtures (95%, 75%, 50% and 25% oxygen). Following a 30 minute equilibration, fluorescent probes (4,000 and 17,000 MW) were added to the incubation media on the mucosal side. The rate of probe accumulation on the serosal side was determined before and after the addition of 1 of 4 substrates to the mucosal media: mannitol (an osmotic control), glucose (which is transported, phosphorylated, and metabolized), 2-dcoxyglucose (a glucose analog which is transported and phosphorylated hut not metabolized) or 3-o-methylglucose (a glucose analog which is transported but not phosphorylated or metabolized). In the 95%, 75% and 50% oxygen groups, glucose and 2-deoxyglucose increased (p<'0.05j the permeation rate of the 17,000 MW probe whereas mannitol and 3-omethylglucose did not. Glucose and 2-deoxyglucose also increased (p<0.05) the permeation rate of the 4,000 MW probe in the 95% and 75% groups, but mannitol and 3-o-methylglucose did nol. The effect of the glucose and 2-deoxyglucose on the permeation rate of both probes was more pronounced (p<0.()5) the lower the oxygénation level. These initial results suggest that the provision of solutes that are subject to phosphorylation may exacerbate the loss of gastrointestinal barrier function found during hypoxia. Although the early provision of nutrients is an important intervention in acutely injured patients, care must be taken to ensure that gaslrointestinal perfusion is adequate to allow substrate metabolism and prevent further compromise in gastrointestinal function.
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M3 - Article
AN - SCOPUS:4243977610
SN - 0148-6071
VL - 22
SP - S3
JO - Journal of Parenteral and Enteral Nutrition
JF - Journal of Parenteral and Enteral Nutrition
IS - 1
ER -