کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2789709 1154522 2007 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A Light and Electron Microscopical Study of the Tragulid (Mouse Deer) Placenta
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شناسی تکاملی
پیش نمایش صفحه اول مقاله
A Light and Electron Microscopical Study of the Tragulid (Mouse Deer) Placenta
چکیده انگلیسی

The Tragulidae are the living relics of the basal ruminant stock. They have a diffuse placenta, with no aggregations of the placental villi into localised placentomes characteristic of all other ruminants. Despite this difference, this ultrastructural and immunocytochemical investigation demonstrates that in Tragulus the trophoblast binucleate cell (BNC) plays the same central role in development and structure as in all other ruminants. It shows an identical development and ultrastructure, produces granules reactive with bovine placental lactogen and pregnancy associated glycoprotein antibodies, and migrates when mature through the trophoblast tight junction to fuse into a mosaic of syncytial plaques from which the granules are released to the mother and which have replaced the uterine epithelium. Unlike the persistent plaques in the sheep and goat placenta, in Tragulus they are transient, dying by apoptosis with the fragments phagocytosed by the trophoblast. This brings the trophoblast into direct endotheliochorial apposition to maternal tissue until BNC migration and fusion replace the dead plaque. This intimate fetomaternal confrontation has not been shown in any other ruminant, and could be a relic of the evolutionary development of the synepitheliochorial from the original basic eutherian endo- or hemo-chorial placenta.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Placenta - Volume 28, Issue 10, October 2007, Pages 1039–1048
نویسندگان
, , , ,