Syncytiotrophoblast 3560044 217377092 2008-06-05T19:42:21Z Nouse4aname 3858210 not just humans {{Infobox Embryology | Name = {{PAGENAME}} | Latin = | GraySubject = 6 | GrayPage = 47 | Image = Gray36.png | Caption = Primary chorionic villi. Diagrammatic. | Image2 = Gray37.png | Caption2 = Secondary chorionic villi. Diagrammatic. | System = | CarnegieStage = 5a | Days = 8 | Precursor = | GivesRiseTo = | MeshName = Syncytiotrophoblasts | MeshNumber = A16.254.085.162 | DorlandsPre = s_32 | DorlandsSuf = 12777200 | }} '''Syncytiotrophoblasts''' are [[multinucleated]] cells found in the [[placenta]] of embryos. They are the outer syncytial layer of the [[trophoblast]]s and actively invade the [[uterus|uterine wall]]. They form the outermost [[fetus|fetal]] component of the placenta (also known as 'syntrophoblast') and massively increase the surface area available for nutrient exchange between the mother and the fetus. Cells from the [[syncytiotrophoblast]] secrete [[progesterone]] in addition to [[human chorionic gonadotropin]] (hCG); the latter prevents degeneration of the [[corpus luteum]]. Progesterone serves to maintain the integrity of the uterine lining, and until the syncytiotrophoblast is mature enough to secrete enough progesterone (in the fourth month of embryonic development), it is aided by the corpus luteum graviditatis. <ref>Langman's Medical Embryology, 10th Edition. T.W. Sadler. p. 34</ref> {{developmental-biology-stub}} ==Additional images== <gallery> Image:Gray12.png|Section through embryonic area of Vespertilio murinus to show the formation of the amniotic cavity. </gallery> ==See also== * [[Syncytium]] * [[Cytotrophoblast]] ==External links== * {{BUHistology|19908loa}} - "Female Reproductive System: placental villi" * [http://www.nature.com/nm/journal/v4/n11/images/nm1198_1244.gif ''Nature (Journal) Diagram''] * {{cite journal | author = Musicki B, Pepe G, Albrecht E | title = Functional differentiation of placental syncytiotrophoblasts during baboon pregnancy: developmental expression of chorionic somatomammotropin messenger ribonucleic acid and protein levels. | journal = J Clin Endocrinol Metab | volume = 82 | issue = 12 | pages = 4105–10 | year = 1997 | pmid = 9398722 | doi = 10.1210/jc.82.12.4105}} [http://jcem.endojournals.org/cgi/content/abstract/82/12/4105/ Article] * [http://sprojects.mmi.mcgill.ca/embryology/earlydev/week1/cyto-syncytio.html Diagram at McGill] * {{eMedicineDictionary|Syncytiotrophoblast}} {{Embryology}} [[Category:Non-terminally differentiated (blast) cells]][[Category:Embryology]] <!--Other languages--> [[es:Sincitiotrofoblasto]] [[fr:syncytiotrophoblaste]]