Bentin-Ley U
Fertility Unit G114-F, Department of Obstetrics and Gynaecology, Herlev Hospital, University of Copenhagen, Herlev Ringvej, Denmark.
Hum Reprod. 2000 Dec;15 Suppl 6:67-73.
Endometrial pinopodes, hormone-dependent protrusions of the endometrial apical plasma membrane, have been suggested as indicators of endometrial receptivity. The lifespan of endometrial pinopodes appears to be tightly regulated. Interestingly, considerable interpatient variations according to the onset of pinopode formation have been observed. In normal fertile women, pinopodes are present on days 6-8 post-ovulation, whereas pinopode formation is observed 1-2 days earlier in patients undergoing controlled ovarian hyperstimulation. In oocyte recipients treated with oestradiol and progesterone in hormone-controlled cycles, pinopode formation seems to be delayed. In-vitro experimental studies on human blastocyst attachment to an artificial endometrium indicate a preference for human blastocysts to attach to pinopode presenting areas on the endometrial surface. Transmission electron microscopy shows that the blastocysts do not attach to the apical plasma membrane of pinopode presenting cells. Trophoblast cells display contact with endometrial epithelial cells at the lateral plasma membranes by sharing apical junctional complexes. The function of endometrial pinopodes during human blastocyst implantation still remains to be elucidated. Ultrastructural studies indicate that the pinopode presenting apical plasma membrane does not participate directly in embryo-endometrial interactions.
子宫内膜微绒毛，即子宫内膜顶端质膜的激素依赖性突起，已被认为是子宫内膜容受性的指标。子宫内膜微绒毛的寿命似乎受到严格调控。有趣的是，根据微绒毛形成的起始时间，已观察到患者之间存在相当大的差异。在正常可育女性中，微绒毛在排卵后第6 - 8天出现，而在接受控制性卵巢过度刺激的患者中，微绒毛形成时间要早1 - 2天。在激素控制周期中接受雌二醇和孕酮治疗的卵母细胞受体中，微绒毛形成似乎延迟。关于人囊胚附着于人工子宫内膜的体外实验研究表明，人囊胚更倾向于附着在子宫内膜表面有微绒毛的区域。透射电子显微镜显示，囊胚并不附着于有微绒毛细胞的顶端质膜。滋养层细胞通过共享顶端连接复合体，在侧质膜处与子宫内膜上皮细胞接触。人囊胚着床期间子宫内膜微绒毛的功能仍有待阐明。超微结构研究表明，有微绒毛的顶端质膜并不直接参与胚胎 - 子宫内膜的相互作用。
