The type of sodium-coupled solute modulates small bowel mucosal injury, transport function, and ATP after ischemia/reperfusion injury in rats.
OBJECTIVE
Gastrointestinal function may be impaired after severe injury, hampering tolerance to enteral nutrition. The purpose of this study was to determine how different sodium-coupled solutes modulate gut function after ischemia/reperfusion (I/R) in a rodent model.


METHODS
At laparotomy, rats had jejunal sacs filled with (glucose + alanine), glucose, glutamine, alanine, or mannitol (osmotic control), followed by superior mesenteric artery clamping for 60 minutes and 30 minutes of reperfusion. After reperfusion, sacs were harvested for morphologic examination, adenosine triphosphate (ATP) assay, or mounted in an Ussing chamber.


RESULTS
Small intestinal epithelial absorptive capacity, as assessed by changes in short-circuit current in response to glucose, after gut I/R, was decreased by alanine or (glucose + alanine) but not glucose or glutamine alone and correlated with changes in tissue ATP. Gut I/R caused a significant morphologic injury that was worsened by alanine or (glucose + alanine) but lessened by glucose or glutamine alone.


CONCLUSIONS
During gut I/R, alanine can enhance gut injury, deplete energy (ATP), and impair gut absorption, whereas glucose or glutamine is protective against injury and can maintain absorptive capacity and ATP. These results suggest that solutes (such as alanine), which further stress an already metabolically stressed bowel, should be cautiously administered to critically ill patients whereas those solutes that contribute to energy production (such as glucose and glutamine) may be safely continued.
Kozar
Rosemary A
RA
Department of Surgery, University of Texas-Houston School of Medicine, Houston, Texas 77030, USA. Rosemary.A.Kozar@uth.tmc.edu
Schultz
Stanley G
SG
Hassoun
Heitham T
HT
Desoignie
Roland
R
Weisbrodt
Norman W
NW
Haber
Marian M
MM
Moore
Frederick A
FA
D000255:Adenosine Triphosphate / Q000378:metabolism; D000409:Alanine / Q000378:metabolism / Q000494:pharmacology; D000596:Amino Acids / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D004338:Drug Combinations; D005947:Glucose / Q000378:metabolism / Q000494:pharmacology*; D005973:Glutamine / Q000378:metabolism / Q000494:pharmacology; D007413:Intestinal Mucosa / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D007511:Ischemia / Q000378:metabolism*; D007583:Jejunum / Q000098:blood supply* / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism
D000596:Amino Acids; D004338:Drug Combinations; D005973:Glutamine; D000255:Adenosine Triphosphate; D012964:Sodium; D005947:Glucose; D000409:Alanine