Intestinal metabolism after ischemia-reperfusion

Abstract

Purpose: This study explores the effects of ischemia-reperfusion on various metabolic aspects of the small intestine. Methods: Intestinal ischemia-reperfusion was obtained by clamping and unclamping the superior mesenteric artery in adult rats. Four groups of animals were studied: (A) sham operation for 150 minutes, (B) 90-minute intestinal ischemia, (C) 150-minute intestinal ischemia, and (D) 90-minute intestinal ischemia followed by 60-minute reperfusion. Body temperature was maintained at normothermia (36.5 to 37.5°C). Concentrations of intestinal glucose, succinate, lactate, amino acids, phosphocholine (PC), glycerophosphocholine (GPC), choline, and phosphoenergetics were measured using magnetic resonance spectroscopy of freeze-clamped small intestine extracts. Results: Intestinal ischemia (groups B and C) alone caused a significant drop in glucose and phosphoenergetics but caused an increase in amino acids, succinate, and lactate. Ischemia and ischemia-reperfusion decreased PC and GPC but increased choline. After intestinal reperfusion (group D), no recovery of phosphoenergetics was observed, but there was partial recovery of glucose, succinate, lactate, and amino acids. Conclusions: There is no recovery of phosphoenergetics after 90 minutes of intestinal ischemia followed by 60 minutes of reperfusion. Partial recovery of glucose, succinate, lactate, and amino acids may reflect equilibration of these metabolites between damaged cells and extracellular fluid. J Pediatr Surg 35:759-764. Copyright © 2000 by W.B. Saunders Company.