AJP - Gastrointestinal and Liver Physiology, Vol 251, Issue 1 124-G131, Copyright © 1986 by American Physiological Society
Ileal hyperplastic response to starvation in the rat
P. R. Holt, S. Wu and K. Y. Yeh
The ability to respond to changes in the external and internal environments
is a fundamental characteristic of intestinal structure and function. We
compared the responses of the rat proximal and distal small intestine to
the stresses of fasting and refeeding in the rat. In the duodenum, 3 days
of starvation caused villus and crypt hypoplasia, reduced incorporation of
[3H]thymidine into crypt cells, decreased cell migration rate on the
villus, and lowered specific and total activities of several cellular
enzymes. These changes were reversed by 1 day of refeeding. In contrast,
mucosal hypoplasia did not occur in the ileum during fasting, and the
specific activities of the disaccharidases were increased after 3 days of
starvation. However, ileal [3H]thymidine incorporation, thymidine kinase
activity, and ornithine decarboxylase activity decreased during starvation.
These effects were also reversed by refeeding. The results of these studies
illustrate differing responses for the proximal and distal small intestine
and suggest the presence of distinctly differing mechanisms for the control
of their mucosal mass and enzyme activities.
