What is trophoblast invasion?
What is trophoblast invasion?
Trophoblast invasion can be seen as a tightly regulated battle between the competing interests of the survival of the fetus and those of the mother. Each of these functions has multiple overlapping control systems so that trophoblast invasion is a finely controlled balance of competing mechanisms.
What does the trophoblast differentiate to?
The trophoblast proliferates and differentiates into two cell layers at approximately six days after fertilization for humans. A single-celled inner layer of the trophoblast. A thick layer that lacks cell boundaries and grows into the endometrial stroma.
What is failure of trophoblast invasion?
Failure of trophoblast invasion and spiral artery transformation occurs in preeclampsia and fetal growth restriction (FGR); these processes are not well understood. Recent studies have suggested that cytotrophoblasts that invade spiral arteries mimic the endothelial cells they replace and express PECAM-1.
What does the trophoblast release?
As early as three days after fertilization, the trophoblasts—the major cell type of the placenta—begin to make human chorionic gonadotropin (hCG), a hormone which insures that the endometrium will be receptive to the implanting embryo.
What is the significance of trophoblast layer?
Trophoblasts are cells that form the outer layer of a blastocyst, which provides nutrients to the embryo, and then develop into a large part of the placenta.
What is acute Atherosis?
Acute atherosis is a maternal vascular lesion observed regularly in cases of pre-eclampsia and idiopathic intrauterine growth retardation. This vasculopathy is characterized by fibrinoid necrosis of the vessel wall, an accumulation of lipid-laden macrophages, and a mononuclear perivascular infiltrate.
What is the function of trophoblast in a blastocyst?
The trophoblast forms the outer layer of the blastocyst, providing the embryo with nutrients and giving rise to the outer chorionic sac and the fetal component of the placenta.
Why is it important to limit the depth of trophoblast invasion?
Dysregulation of the finely controlled process of trophoblast invasion can lead to a wide spectrum of pregnancy abnormalities. Excessively shallow invasion has been implicated in fetal intrauterine growth restriction and preeclampsia, one of the most common pregnancy complications.
What is Atherosis in placenta?
Abstract. Acute atherosis is unique vascular changes of the placenta associated with poor placentation. It is characterized by subendothelial lipid-filled foam cells, fibrinoid necrosis of the arterial wall, perivascular lymphocytic infiltration, and it is histologically similar to early-stage atherosclerosis.
What are the spiral arteries?
Spiral arteries are small arteries which temporarily supply blood to the endometrium of the uterus during the luteal phase of the menstrual cycle. The spiral arteries are converted for uteroplacental blood flow during pregnancy, involving: Loss of smooth muscle & elastic lamina from the vessel wall.