Figure 5

Immunohistochemical detection of leptin and leptin receptor in the utero-placental compartments during pregnancy. Immunohistochemical localization of leptin (Lep; A, C, E) and leptin receptor (LepR; B, D, F) in the utero-placental compartments (Ut/Pl) during pregnancy. (A) Lep signals are strong in fetal trophoblast cells (open arrowheads) of the placental labyrinth at mid-gestation, while maternal decidual cells (solid arrowheads) stain more weakly and blood vessel endothelial cells (thin arrows) show sporadic signals. (B) LepR positive trophoblasts (open arrowheads) are present in the placental labyrinth at mid-gestation. LepR immunoreactivity is less intense in decidual cells (solid arrowheads) and in blood vessel endothelium (thin arrows). (C) Strong Lep immunoreactivity is evident in fetal trophoblast cells (open arrowheads) of the placental labyrinth at prepartum luteolysis with weaker signals in decidual cells (solid arrowheads) and occasional staining in the endothelium (thin arrows). Intense signals are detected in trophoblasts at the base of the labyrinth invading large maternal vessels (inset). (D) LepR positive trophoblast cells (open arrowheads) are shown in the placental labyrinth at prepartum luteolysis with less intense staining in maternal decidual cells (solid arrowheads) and blood vessel endothelium (thin arrows). The inset shows positive reaction in fetal trophoblast cells invading large maternal vessels at the base of the labyrinth. (E) Lep staining is present in the epithelial cells of the glandular chambers (solid arrows) and sporadic signals are also visible in the stroma (solid arrowheads). Positive staining in the myometrium is shown in the inset. (F) In the glandular chambers, epithelial cells stain positive for LepR (solid arrows) and stromal signals (solid arrowheads) are also present. Positive immunoreactivity in the myometrium is presented in the inset. MV: maternal vessel, MY: myometrium.