Background:In the suckling rat, massive bowel resection provokes intestinal malabsorption that leads to diminished growth. The object of this report was to test whether neurotensin, intestinal trophic peptide, enhances postresection intestinal adaptation, improving absorption and reducing the adverse effects of resection on growth.Methods:Fifty-seven 15-day-old suckling Wistar rats were divided into four groups: 41 rats were subjected to resection of 90% of their small bowel, while the rest (n = 16) under went laparotomy. Half of the animals, resected and laparotomized, were treated with neurotensin for 30 days. The body weight was monitored, and samples of bone and intestinal mucosa were obtained at the end of the study period for analysis. Blood was tested to determine iron, ferritin, folic acid, and vitamin B12levels.Results:The resected animals lost body weight regardless of neurotensin administration. In the resected animals, femur weight increased significantly when they received neurotensin. Bowel resection provokes significant increases in the intestinal mucosa (crypts and villi), but after neurotensin administration, significant increases were detected only in the jejunum of the resected animals but not in the ileum of laparotomized rats. In the resected animals, signficant decreases in iron, ferritin, folic acid, and vitamin B12levels were observed. The postresection administration of neurotensin only produced a significant rise in the ferritin concentration.Conclusions:In the suckling rat, neurotensin enhances the intestinal proliferative phenomenon but does not improve the course of medium-term postresection growth.