Digitonin cytochemistry reveals cholesterol-rich vesicles in uterine epithelial cells.

Freeze-fracture cytochemistry with digitonin has been used to examine the cholesterol content of the large apical vesicles of uterine epithelial cells. The vesicles are found to have cholesterol-rich membranes which supports the view that they are involved in cell secretion. We comment on the possible role of the vesicles in implantation.