Reflexive gap junctions on uterine luminal epithelial cells

Freeze-fracture electron microscopy has been used to search for reflexive gap junctions on apical projections of uterine epithelial cells in the rat. These structures were found in 5 of 6 animals in the study and consisted of from 15 to over 70 intramembranous particles which ranged in size from 7 to 9 nm. Some suggestions on the function of these enigmatic junctions are discussed.