Alanyl Glutamine-Enriched Total Parenteral Nutrition Restores Intestinal Adaptation After Either Proximal or Distal Massive Resection in Rats

Abstract

This study was designed to determine whether alanyl glutamine-containing total parenteral nutrition (TPN) can restore the impaired adaptive process of the remaining intestine, observed with administration of conventional TPN, after massive small-bowel resection. Seventy-four male Sprague-Dawley rats weighing 250 g were randomly divided into seven groups. Group I rats (n = 10) were killed after overnight fasting. Group II animals (n = 32) underwent massive small bowel resection (85%) with preservation of the first 15 cm of jejunum. Group III animals (n = 32) were also submitted to massive small-bowel resection with preservation of 15 cm of terminal ileum. Three different TPN solutions were prepared. Solution A was a conventional formulation that did not contain glutamine. Solution B contained 1.88 times the amino acid concentration of solution A. Solution C was prepared by adding alanyl glutamine (2 g/100 mL) to solution A. Solutions B and C were isonitrogenous and isocaloric. Each solution was infused to groups II and III, which were subdivided into groups IIA (n = 10), IIB (n = 11), IIC (n = 11), IIIA (n = 10), IIIB (n = 11), and IIIC (n = 11). After 1 week of TPN (270 kcal/kg per day), the experimental animals were killed and the intestine was taken for examination. Final body weight did not differ significantly among the groups, and there was no difference in nitrogen balance among the animals that received solution B or C. Mucosal wet weight, protein, RNA, maltase, and sucrase in duodenum, remaining jejunum, and remaining ileum of animals receiving solution C (groups IIC and IIIC) significantly increased (p < .05) compared with animals receiving solution A or B (groups IIA, IIB, IIIA, and IIIB). Villus height in the duodenum and remaining jejunum of animals receiving solution C (groups IIC and IIIC) was significantly increased (p < .05) compared with animals receiving solution A or B (groups IIA, IIB, IIIA, and IIIB). Mucosal DNA content of group IIC was significantly increased (p < .05) compared with groups IIA and IIB. Diamine oxidase activity in the duodenum was significantly increased in group IIIC animals compared with groups IIA, IIB, and IIC. These results strongly suggest that, after massive resection, adaptation of the remaining intestine, whether jejunal or ileal segment, can be promoted by administration of alanyl glutamine-enriched TPN. (Journal of Parenteral and Enteral Nutrition 17:236-242, 1993)