INTESTINAL ADAPTATION AFTER MASSIVE PROXIMAL SMALL-BOWEL RESECTION INTHE PIG

Background: Small-intestinal adaptation to resection has been extensiv ely studied in rats. The present study investigates morphology, crypt cell proliferation, and disaccharidase activities of the remaining sma ll intestine and colon after 75% proximal resection of porcine small i ntestine. Methods: Specimens were obtained from the proximal jejunum, middle and distal ileum, and proximal colon preoperatively (n = 5) and 14 weeks after small-bowel transection (n = 5) or resection (n = 5). Proliferation was analyzed immunohistochemically with the Ki-67 antige n MIB-1. Disaccharidase activities were determined in accordance with the method of Dahlqvist. Results: In addition to macroscopic enlargeme nt, resection markedly increased the villi and crypts of the remaining small bowel. Crypt cell proliferation decreased with advancing age af ter transection but remained at the preoperative level after resection . Specific, but not total, activities of maltase and sucrase in the mi d-ileum decreased after resection. Conclusion: Small-intestinal adapta tion in the pig involves macroscopic enlargement and a prompt increase in villus size, which is associated with high crypt cell proliferatio n.