Calmodulin in epithelial intestinal cells during rat development

Calmodulin was immunocytochemically localized in the brush borders of rat intestinal epithelial cells from the tip to the base of the villi, from day 18 of fetal life up to the adult stage. The early (14th day) fetal cells, like the adult crypt cells, were not immunoreactive, although their calmodulin content was equal to that of the mature cells from the tips of the villi.