Epithelial cell migration in the intestine of the young mouse

Abstract

Autoradiographs were made of sections of the duodenal region of the intestine from 3 stages of preweaning mice, sacrificed at intervals after injection of thymidine- 3H. The results clearly show that significant cell migration does occur in the intestinal epithelium of the duodenum at stages when dramatic cytodifferentiative changes are taking place in this tissue. The rate of epithelial cell migration (in terms of distance, in μ-traveled in 48 hours) is, in all of the 3 preweaning stages examined, lower than in the adult duodenum. Although the villi elongate, reaching a length equivalent to that of adult villi by 20–24 days after birth. the rate of epithelial cell migration does not increase during the preweaning period. As the villi lengthen, the time required for a cell to migrate from the intestinal crypt to the villus tip becomes increasingly greater. The observations in this study tend to support the idea that the process of villus elongation prior to weaning is regulated in the mouse duodenum by variation of the rate of cell extrusion from the villus tip.