Effect of glutamine-supplemented total parenteral nutrition on recovery of the small intestine after starvation atrophy.

Intestinal atrophy was induced in rats by infusion of 5% dextrose for 7 days with only oral water allowed. Compared with control animals fed standard rat chow (Purina Mills, St. Louis), the starved animals lost 30.5% of their initial body weight, 34.7% mucosal wet weight, 68.3% mucosal nitrogen content, 36.7% mucosal thickness, and 38.6% villous height and had variable losses of mucosal disaccharidase activities. Three groups of depleted rats were then refed with different regimens. One group was refed with standard Purina rodent chow (n = 15); a second group with a standard total parenteral nutrition (TPN) solution containing 16% glucose, 2.8% fat, and 4.25% standard amino acids (Travasol 8.5%, Baxter Healthcare Corporation, Deerfield, IL) (n = 15); and the third group with a TPN solution of 16% glucose, 2.8% fat, 2.75% standard amino acids, and 1.5% glutamine (n = 15). After 7 days of refeeding, rats were killed to determine the degree of intestinal recovery. Animals refed with standard TPN solution showed no significant recovery of intestinal mucosal weight, mucosal nitrogen content, villous height, mucosal thickness, or mucosal disaccharidase activities. Animals refed with glutamine-supplemented TPN solution demonstrated significant recovery of all parameters but not back to normal. Oral rodent chow completely restored intestinal anatomy and function. The addition of glutamine to TPN solutions significantly improved recovery of the intestine from starvation atrophy, and additional efforts to make it commercially available are indicated. This study again confirms the preferable use of a regular oral diet when clinically feasible and safe.