Abstract
Expression of the neurotensin neuromedin N (NT/N) gene is developmentally regulated in a temporal- and spatial-specific pattern in the small bowel. The purpose of our study was to determine 1) whether the temporal expression of NT/N could be altered by ectopic placement of small bowel and 2) whether the spatial-specific expression of NT/N could be altered by different diets. We found that the relative temporal pattern of NT/N expression was unchanged in rat jejunal and ileal xenografts implanted into the flanks of athymic nude mice. To determine whether the spatial-specific pattern of NT/N expression could be altered by different luminal nutrients, 28-day-old rats were randomized to receive chow or chemically defined liquid diets for 60 days at which time the jejunoileum was divided into eight equal segments, and NT/N expression was analyzed. The normal pattern of increasing levels of NT/N mRNA along the jejunum-to-ileum axis was not altered by any of the liquid diets. In contrast to NT/N, we found that expression of sucrase-isomaltase varied greatly depending on both location and type of luminal nutrients. We conclude that the strict temporal and spatial-specific pattern of NT/N expression is not affected by either location or luminal contents, thus suggesting an intrinsic program of NT/N gene expression. Furthermore, we speculate that the NT/N gene may provide a useful endocrine paradigm to investigate the factors regulating the establishment and maintenance of certain cell lineage specific patterns along the cephalocaudal axis of the gut.
Original language | English (US) |
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Pages (from-to) | G875-G882 |
Journal | American Journal of Physiology - Gastrointestinal and Liver Physiology |
Volume | 267 |
Issue number | 5 30-5 |
DOIs | |
State | Published - 1994 |
Externally published | Yes |
Keywords
- entero-endocrine cell
- gut differentiation, ontogeny
- regional gene expression
ASJC Scopus subject areas
- Physiology
- Hepatology
- Gastroenterology
- Physiology (medical)