Differential jejunal and colonic adaptation due to resection and IGF-I in parenterally fed rats

Patients with severe short-bowel syndrome (SBS) often require long-term tot al parenteral nutrition (TPN) to maintain their nutritional status because of limited intestinal adaptation. Growth factors, including insulin-like gr owth factor I (IGF-I), are under investigation to promote intestinal adapta tion and tolerance to oral feeding. We investigated structural and function al adaptation of the jejunum and colon in four groups of rats maintained wi th TPN for 7 days after a 60%, jejunoileal resection and cecectomy or sham surgery and treatment with IGF-I or vehicle. Resection alone did not stimul ate jejunal growth. IGF-I significantly increased jejunal mucosal mass, ent erocyte proliferation, and migration rates. IGF-I decreased jejunal sucrase specific activity and reduced active ion transport and ionic permeability; resection alone had no effect. In contrast, resection significantly increa sed colonic mass and crypt depth but had no effect on active ion transport or ionic permeability. IGF-I had minimal effects on colonic structure. IGF- I but not resection stimulates jejunal adaptation, whereas resection but no t IGF-I stimulates colonic growth in rats subjected to a model for human SB S. IGF-I treatment may improve intestinal adaptation in humans with SBS.