title: Adaptation of enteroendocrine cells in response to jejunal-ileal transposition in the rat.
abstract: OBJECTIVE
  Enteroendocrine cell subpopulations are uniquely distributed along the crypt-villus and cephalocaudal axes of the small intestine. These regional differences in enteroendocrine cell expression, which are maintained in spite of rapid turnover of the epithelium, serve as descriptive markers of physiological differences along the length of the bowel. This study aimed to determine the influence of luminal contents on the maintenance of regional differentiation patterns of enteroendocrine and enterocytic phenotypes.
  
  
  METHODS
  Sections of jejunum and ileum were surgically transposed in rats, leaving the innervation and blood supply to the transposed segments intact. The animals were killed 1, 4, and 8 weeks after surgery. Enteroendocrine cell subpopulations and enterocytic cell markers were studied immunohistochemically.
  
  
  RESULTS
  No change in regional expression patterns was seen in response to the altered luminal environment by any of the enterocytic markers and four of the five enteroendocrine cell subpopulation markers. Eight weeks after surgery, the number of gastrin-expressing enteroendocrine cells increased in ileal segments transplanted proximally.
  
  
  CONCLUSIONS
  Although luminal signals can affect intestinal stem cells to alter their proliferation rates, the luminal environment has only limited effects on the regional-specific expression of enteroendocrine or enterocytic products.
authors.affiliation: Department of Pathology, Washington University School of Medicine, St. Louis, Missouri.
authors.forename: K D
authors.initials: KD
authors.lastname: Aiken
authors.forename: W
authors.initials: W
authors.lastname: Yu
authors.forename: J R
authors.initials: JR
authors.lastname: Wright
authors.forename: K A
authors.initials: KA
authors.lastname: Roth
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D015415:Biomarkers; D002352:Carrier Proteins / Q000378:metabolism; D004702:Endocrine Glands / Q000166:cytology / Q000502:physiology*; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005755:Gastrins / Q000378:metabolism; D004763:Glucagon-Like Peptides; D007082:Ileum / Q000637:transplantation*; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000166:cytology / Q000502:physiology*; D007583:Jejunum / Q000637:transplantation*; D008099:Liver / Q000378:metabolism; D008297:Male; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D010455:Peptides / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D016042:Transplantation, Heterotopic
chemical_list: D015415:Biomarkers; D002352:Carrier Proteins; C490174:Fabp7 protein, rat; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005755:Gastrins; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D010455:Peptides; D004763:Glucagon-Like Peptides; C015236:glucagon-like-immunoreactivity