Initiation of placental lactogen-I production by blastocysts growing on a two-dimensional surface and in hanging drops.
Initiation of placental lactogen-I production by blastocysts growing on a two-dimensional surface and in hanging drops.
复制标题
通过在二维表面和悬滴中生长的囊胚启动胎盘催乳素-I 的产生。
DOI：
10.1002/jez.1402600214
复制
发表时间：
1991
期刊：
影响因子：
--
通讯作者：
Nagy,F
中科院分区：
文献类型：
--
作者：
Nieder,GL;Nagy,F
小鼠囊胚在围着床期经历蛋白质分泌程序，包括妊娠第6天胎盘催乳素-I（mPL-I）的初始产生。虽然第5天收集的囊胚在塑料培养皿上培养形成生长物时也会产生mPL-I，但尚不清楚胚胎在体外培养期间是否具有产生mPL-I的内在能力，或者是否需要特定的子宫影响。早期的实验还表明，滋养层细胞附着在稳定的表面可能是合成mPL-I的先决条件。通过检查在二维组织培养皿表面或悬滴中培养的第3天和第4天胚胎的mPL-I产量来解决这两个问题。通过免疫组织化学测定细胞内mPL‐I的存在，而分泌的激素通过其在二维电泳凝胶中的已知位置检测。这些实验表明，这些早期胚胎确实具有在各种培养条件下体外进行mPL-I生产的内在程序。mPL-I的合成发生在悬浮在悬滴中的胚胎中，以及那些散布在固体二维表面上的胚胎中，因此表明粘附到表面上不是产生这种激素所必需的。尽管在含有BSA作为唯一大分子的培养基中培养的胚胎中观察到一些mPL-I合成，但在其支持附着的培养皿中或悬滴系统中包含纤连蛋白刺激mPL-I分泌。与纤连蛋白补充相比，两种培养系统中的血清补充进一步增加了胚胎的生长和分化，以及mPL-I分泌。
The mouse blastocyst undergoes a program of protein secretion during the periimplantation period including the initial production of placental lactogen‐I (mPL‐I) on day 6 of pregnancy. Although blastocysts collected on day 5 also produce mPL‐I when cultured to form outgrowths on plastic dishes, it was not known if embryos have an intrinsic ability to produce mPL‐I during culture in vitro, or if a specific uterine influence is necessary. Earlier experiments also suggested that attachment of the trophoblast to a stable surface may be a prerequisite for synthesis of mPL‐I. Both questions were addressed by examining mPL‐I production by day 3 and day 4 embryos cultured either on a two‐dimensional tissue culture dish surface or in hanging drops. The presence of intracellular mPL‐I was assayed by immunohistochemistry, while the secreted hormone was detected by its known position in two‐dimensional electrophoresis gels. These experiments demonstrated that these earlier stage embryos do have an intrinsic program for mPL‐I production which proceeds in vitro under various culture conditions. Synthesis of mPL‐I occurred in embryos suspended in hanging drops as well as in those spreading on a solid two‐dimensional surface, thus showing that adhesion to a surface is not required for production of this hormone. Although some mPL‐I synthesis was seen in embryos cultured in medium containing BSA as the sole macromolecule, the inclusion of fibronectin either in dishes, where it supports attachment, or in the hanging drop system stimulated mPL‐I secretion. Serum supplementation in both culture systems further increased growth and differentiation of the embryo, as well as mPL‐I secretion, compared to fibronectin supplementation.