Jojović M, Wolf F, Mangold U
Department of Neuroanatomy, Anatomical Institute of the University of Hamburg, Universitätskrankenhaus Eppendorf, Germany.
Anat Embryol (Berl). 1998 Aug;198(2):133-9. doi: 10.1007/s004290050171.
The development and survival of rat embryos in whole-embryo culture is limited by the lack of any maternal blood circulation in a purely fetal placenta. If the resulting placental insufficiency could be overcome for some time by an increase of the placental exchange area, a prolonged culture period would result and facilitate the development of embryos. In the present study, several attempts to stimulate proliferation and growth of the fetal placenta were made by the addition of vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and progesterone to the culture medium. Rat embryos were routinely explanted with their embryonic membranes at 10.5 days of gestation. Decidua, parietal yolk sac, Reichert's membrane and the layer of superficial trophoblastic giant cells were removed. The explants were cultured and gassed continuously for 24 h in rotating plastic tubes containing rat serum, diluted to 50% with modified COON's F12 medium. Either of the two growth factors or progesterone were added to each culture tube and a control group was cultured without any factor. After the addition of each of these factors the stimulatory effect on placental growth was assessed by morphometric evaluation of several placental parameters from semithin cross-sections: On adding each of the factors the whole cross-sectional area of the placenta significantly increased, as did the area of the fetal placental mesenchyme. VEGF also increased the area of the trophoblast, and the area of the blood vessels enclosed within the trophoblast, by an average of 9.4% and 23.6%, respectively. Thus, VEGF treatment resulted in a measurable extension of the exchange area of the fetal placenta.
在纯胎儿型胎盘中，由于缺乏母体血液循环，大鼠胚胎在全胚胎培养中的发育和存活受到限制。如果能通过增加胎盘交换面积在一段时间内克服由此产生的胎盘功能不全，那么培养期将会延长，并促进胚胎发育。在本研究中，通过向培养基中添加血管内皮生长因子（VEGF）、表皮生长因子（EGF）和孕酮，进行了几次刺激胎儿胎盘增殖和生长的尝试。妊娠10.5天时，将大鼠胚胎及其胎膜常规移出。去除蜕膜、壁层卵黄囊、赖歇特氏膜和表层滋养层巨细胞层。将外植体在含有大鼠血清且用改良的COON's F12培养基稀释至50%的旋转塑料管中连续培养并通气24小时。向每个培养管中添加两种生长因子或孕酮中的一种，设置一个不添加任何因子的对照组。添加每种因子后，通过对半薄切片中几个胎盘参数进行形态计量学评估来评估对胎盘生长的刺激作用：添加每种因子后，胎盘的整个横截面积显著增加，胎儿胎盘间充质的面积也显著增加。VEGF还使滋养层面积以及滋养层内血管面积分别平均增加了9.4%和23.6%。因此，VEGF处理导致胎儿胎盘交换面积有可测量的增加。
