Intravenous glutamine fails to improve gut morphology after radiation injury.

Male Sprague-Dawley rats housed in individual metabolic cages received total parenteral nutrients via chronic indwelling internal jugular catheters to determine whether supplementing parenteral nutrition with glutamine would accelerate recovery of small-bowel morphology after abdominal radiation. After recovering from catheter insertion for 3 days they received either 1000 cGy gamma radiation to the abdomen only or no radiation and immediately thereafter received isonitrogenous and isocaloric intravenous solutions containing either 0% or 2% glutamine at 1.58 mL/h for the next 5 days. Intestinal segments were then assayed for whole-bowel deoxyribose nucleic acid content and villus height. Irradiation caused a 40% decrement in these parameters, which were not restored by glutamine supplementation. Therefore, intravenous glutamine supplementation failed to accelerate recovery of small-bowel morphology in this model of combined surgical and radiation injury.