Related Experiment Videos
Ileal hyperplastic response to starvation in the rat.
The American Journal of Physiology
|July 1, 1986
Summary
The rat small intestine responds differently to fasting and refeeding. The duodenum shrinks, while the ileum adapts by increasing enzyme activity, showing distinct control mechanisms.
Area of Science:
- Gastroenterology
- Cell Biology
- Physiology
Background:
- Intestinal structure and function are adaptable to environmental changes.
- The proximal and distal small intestine may exhibit differential responses to nutritional stress.
Purpose of the Study:
- To compare the adaptive responses of the rat proximal (duodenum) and distal (ileum) small intestine to fasting and refeeding.
- To investigate the underlying mechanisms controlling mucosal mass and enzyme activity in different intestinal segments.
Main Methods:
- Induction of starvation for 3 days followed by 1 day of refeeding in rats.
- Assessment of villus and crypt morphology, cell proliferation ([3H]thymidine incorporation), cell migration, and enzyme activities (disaccharidases, thymidine kinase, ornithine decarboxylase).
Main Results:
- Fasting caused duodenal hypoplasia, reduced cell proliferation and migration, and decreased enzyme activity, all reversed by refeeding.
- Ileum did not show mucosal hypoplasia; disaccharidase activity increased during fasting.
- Ileal cell proliferation and specific enzyme activities (thymidine kinase, ornithine decarboxylase) decreased during fasting but were reversed by refeeding.
Conclusions:
- The proximal and distal small intestine exhibit distinct adaptive responses to nutritional stress.
- Different regulatory mechanisms likely control mucosal mass and enzyme activity in the duodenum versus the ileum.