Origin and histogenesis of equine endometrial cups
Moor, R.M.; Allen, W.R.; Hamilton, D.W.
Journal of Reproduction and Fertility. Supplement 1975(23): 391-395
1975
ISSN/ISBN: 0449-3087 PMID: 1060813 Document Number: 85929
A wide range of fetal and maternal tissues were cultured and their ability to secrete gonadotrophin (PMSG) was monitored. High levels of PMSG were produced in culture only by cells from the restricted area of the equine trophoblast known as the chorionic girdle which is an annular band of highly specialized cells at the junction of the allantois and the regressing yolk sac. The morphological appearance of girdle cells after cultivation and after allogeneic grafting to the uterus or testis was identical to that of endometrial cup cells. Firm attachment between the cells of the chorionic girdle and the adjacent endometrium occurs on day 35. Girdle cells then rapidly invade and phagocytose the endometrial epithelium, and migrate into the endometrial glands and the uterine stroma where they differentiate into large, sessile endometrial cup cells.