FTY720, a sphingosine analog, altered placentome histoarchitecture in ewes.

Background: The lysosphingolipid, sphingosine-1-phosphate, is a well-described and potent pro-angiogenic factor. Receptors, as well as the sphingosine phosphorylating enzyme sphingosine kinase 1, are expressed in the placentomes of sheep and the decidua of rodents; however, a function for this signaling pathway during pregnancy has not been established. The objective of this study was to investigate whether sphingosine-1-phosphate promoted angiogenesis within the placentomes of pregnant ewes.

HSPB8 and the Cochaperone BAG3 Are Highly Expressed During the Synthetic Phase of Rat Myometrium Programming During Pregnancy.

The small heat shock protein (HSP) B family of proteins are a group of molecular chaperones that enable tissues to adapt to changes in their local environments during differentiation, stress, or disease conditions. The objective of this research was to characterize the expression of HSPB8 and its cochaperone Bcl2-associated athanogene 3 (BAG3) in nonpregnant (NP) and pregnant rat myometrium during myometrial programming. Rat myometrium was collected from NP and pregnant rats as well as 1 day postpartum (PP) and samples prepared for immunoblot and immunofluorescence analysis.

Effects of long-term progesterone on developmental and functional aspects of porcine uterine epithelia and vasculature: progesterone alone does not support development of uterine glands comparable to that of pregnancy.

In pigs, endometrial functions are regulated primarily by progesterone and placental factors including estrogen. Progesterone levels are high throughout pregnancy to stimulate and maintain secretion of histotroph from uterine epithelia necessary for growth, implantation, placentation, and development of the conceptus (embryo and its extra-embryonic membranes). This study determined effects of long-term progesterone on development and histoarchitecture of endometrial luminal epithelium (LE), glandular epithelium (GE), and vasculature in pigs.

Uterine stretch regulates temporal and spatial expression of fibronectin protein and its alpha 5 integrin receptor in myometrium of unilaterally pregnant rats.

The adaptive growth of the uterus during pregnancy is a critical event that involves increased synthesis of extracellular matrix (ECM) proteins and dynamic remodeling of smooth muscle cell (SMC)-ECM interactions. We have previously found a dramatic increase in the expression of the mRNAs that encode fibronectin (FN) and its alpha5-integrin receptor (ITGA5) in pregnant rat myometrium near to term. Since the myometrium at term is exposed to considerable mechanical stretching of the uterine wall by the growing fetus(es), the objective of the present study was to examine its role in the regulation of FN and ITGA5 expression at late gestation and during labor.