Published online Jun 25, 1996. doi: 10.3748/wjg.v2.i2.69
Revised: January 2, 1996
Accepted: April 20, 1996
Published online: June 25, 1996
AIM: To study the effects of glutamine-supplemented parenteral nutrition on protein metabolism, small intestinal mucosal morphology, and barrier function in endotoxin-treated rats.
METHODS: Thirty-five male Wistar rats were divided randomly into four groups: group A, normal control; group B, enteral nutrition (EN); group C, non-glutamine total parenteral nutrition (TPN); group D, glutamine TPN. Endotoxemia was induced by continuous intravenous infusion of endotoxin at a dose of 2 mg/kg per day throughout the 5-d study period. The small intestinal bacterial translocation rate and contents of mucosal protein, DNA, superoxide dismutase (SOD), malondialdehyde (MDA), adenosine triphosphate (ATP) and secretory immunoglobulin A (sIgA) were determined in mucosal homogenates. Mucosal thickness and villous height were measured with light microscope, and thickness of microvillus was measured with electron microscope.
RESULTS: The bacterial translocation rates of group B and group D were lower than that of group C (P < 0.01). Group D showed increased protein content and DNA content in the small bowel (P < 0.01), and, unlike the other groups, maintained the height of intestinal villi, the thickness of mucosa and the whole small intestine (P < 0.01). Group D showed increased intestinal mucosal contents of ATP and sIgA and decreased contents of SOD and MDA, compared with group C (P < 0.01). All parameters returned to normal levels in group B with EN, which also showed higher villous height and mucosa thickness than group A (P < 0.01).
CONCLUSION: Glutamine can improve gut metabolism, decrease the extent of mucosal atrophy and assist in the maintenance of the mucosal barrier function. Early use of TPN plays an important physiological role in the small bowel.