THE ULTRASTRUCTURE OF HUMAN DECIDUAL AND PREDECIDUAL CELLS

Abstract

Summary. Human decidual cells possess 'gap' junctions but they connect processes from the same cell and do not join neighbouring cells. They are, therefore, unlikely to contribute to the efficiency of the decidua as a mechanical barrier, in contrast to similar junctions in mouse decidua which do join neighbouring cells. Mature human decidual cells are surrounded by a layer of dense extracellular material indistinguishable from the basement membrane of epithelial cells. Predecidual cells in human endometrium in the late luteal phase of the menstrual cycle have 'gap' junctions which, as in pregnant mice, join neighbouring cells.