Progesterone treatment and the progress of early pregnancy reduce desmoglein 1&2 staining along the lateral plasma membrane in rat uterine epithelial cells

Desmosomes in the Uterine Epithelium of Noninvasive Skink Placentae

“…Additionally, in the uterine epithelium of various skinks, a reported change in the distribution of tight junctional proteins occludin and claudin-5 was found which offered strong evidence that the paracellular pathway for exchange between the mother and the embryo becomes more restricted and prevents the passage of water and solutes as gestation progresses (Biazik et al, , 2008, similar to conditions found in rat uterus at the time of implantation (Orchard and Murphy, 2002). A reduction in the number of desmosomes occurs during pregnancy in highly placentotrophic skinks and also during trophoblastic implantation in rats and mice (Illingworth et al, 2000;Preston et al, 2004), thus suggesting that these events are regulated by similar cellular mechanisms.…”

“…Similar changes in desmosomal adhesion occur in the uterine epithelium at the time of implantation in mammals such as rats and mice, which have invasive hemochorial placentation (Illingworth et al, 2000;Preston et al, 2004). In rats and mice, the trophoblast adheres to the apical plasma membrane, displaces individual uterine epithelial cells and penetrates the basal lamina (Finn and Lawn, 1968;Enders and Schlafke, 1971;Schlafke and Enders, 1975).…”

“…In rats and mice, the trophoblast adheres to the apical plasma membrane, displaces individual uterine epithelial cells and penetrates the basal lamina (Finn and Lawn, 1968;Enders and Schlafke, 1971;Schlafke and Enders, 1975). During the invasion, the trophoblastic processes share in the uterine epithelium junctional complexes (Schlafke and Enders, 1975) such that transient ''giant'' desmosomes form at the time of implantation in rats (Preston et al, 2004). The loss of lateral adhesion and cell-to-cell contact helps detach the uterine epithelium from the underlying basal lamina (Schlafke and Enders, 1967).…”

“…Changes in the junctional complexes between uterine epithelial cells are likely to facilitate trophoblast invasion (Illingworth et al, 2000), in particular changes in the number of desmosomes, which are the strongest attachment components of the junctional complex (Enders and Schlafke, 1971). In both rats and mice, the number of desmosomes in uterine epithelial cells decreases during implantation and early pregnancy (Illingworth et al, 2000;Preston et al, 2004), resulting from a redistribution of desmosomes to the apical portion of the lateral plasma membrane as pregnancy proceeds (Preston et al, 2004). Thus, a decrease in lateral adhesion takes place between adjacent uterine epithelial cells during this period, leading to a decrease in cytoskeletal binding (Bazzi and Christiano, 2007).…”

“…Thus, a decrease in lateral adhesion takes place between adjacent uterine epithelial cells during this period, leading to a decrease in cytoskeletal binding (Bazzi and Christiano, 2007). Reduced desmosome numbers increases the plasticity of the uterine epithelium in preparation for implantation and so helps mediate the detachment of the epithelium (Illingworth et al, 2000;Preston et al, 2004). Additionally, trophoblast invasion of the uterine epithelium (Mossman, 1974;Moffett and Loke, 2006) effectively reduces the barrier for the transfer of water and transudates from the blood allowing hemotrophic nutrient transport (Freyer et al, 2003).…”