What do endometrial cups secrete?
Called endometrial cups for their concave shape, they behave much like cells from metastatic tumors, leaving the placenta and migrating into the uterus, where they secrete copious amounts of the well-known pregnancy hormone, equine Chorionic Gonadotrophin (eCG).
Do endometrial cups produce progesterone?
eCG causes the development of multiple follicles on each ovary, which either ovulate or luteinize to form secondary corpora lutea. The secondary corpora lutea produce progesterone which sustains the pregnancy.
What produces equine chorionic gonadotropin?
Equine chorionic gonadotropin (eCG), also known as pregnant mare serum gonadotropin (PMSG) or equine luteinizing hormone, is a glycoprotein hormone secreted by fetal-origin trophoblastic epithelial cells that form the endometrial cups [4,5].
What is the maternal recognition of pregnancy in the mare?
Maternal recognition of pregnancy refers to the sequence of events by which embryo-derived signals prolong luteal function, ultimately assuring ongoing progesterone secretion by the corpus luteum beyond its normal lifespan of the estrous cycle.
When do endometrial cups form in horses?
between approximately 38 days
Endometrial cups in horses are outgrowths appearing in the uterine wall of the pregnant horn between approximately 38 days and 150 of gestation. The cups are structures which vary in shape from oval to irregular and have distinct raised edges, showing an ulcer-like form.
What are endometrial cups in horses?
Endometrial cups in horses are outgrowths appearing in the uterine wall of the pregnant horn between approximately 38 days and 150 of gestation. The cups are structures which vary in shape from oval to irregular and have distinct raised edges, showing an ulcer-like form.
Where does maternal recognition take place in a mare?
The series of events, discussed below, has been termed “Maternal Recognition of Pregnancy.” When the mare ovulates an oocyte, the cells in the wall of the follicle (the structure on the ovary that previously housed the oocyte), undergo a rapid series of change and forms a corpus luteum (CL).
When does maternal recognition of pregnancy occur in cattle?
CSH1 is detectable in maternal serum by Day 50 and peak concentrations are between Days 120 to 130 of gestation [50].
When does maternal recognition of pregnancy occur in mares?
Maternal recognition of pregnancy (MRP) in the mare is an unknown process. In a non-pregnant mare on day 14 post-ovulation (PO), prostaglandin F2α (PGF) is secreted by the endometrium causing regression of the corpus luteum. Prior to day 14, MRP must occur in order to attenuate secretion of PGF.
When does maternal recognition occur?
CSH1 is detectable in maternal serum by Day 50 and peak concentrations are between Days 120 to 130 of gestation [50]. A homodimer of the prolactin receptor (PRLR) and a heterodimer of PRLR and growth hormone receptor (GHR) transduce CSH1 cell signaling [51].
What will be the eventual consequence if maternal recognition of pregnancy fails?
The window of time for maternal recognition of pregnancy to occur is narrow, and failures either in sending or receiving the signal may well be a significant cause of early embryonic death. If, for example, a human embryo fails to secrete adequate amounts of CG in time to rescue its mother’s corpus luteum, it will die.
