Carlone D L, Rider V
Department of Anatomy and Cellular Biology, Tufts University, Boston, Massachusetts 02111.
Biol Reprod. 1993 Oct;49(4):653-65. doi: 10.1095/biolreprod49.4.653.
Cellular proliferation and differentiation are critical components of uterine remodeling prior to embryonic implantation. Recent studies have shown that the ovarian hormones, estrogen and progesterone, modulate these cellular events through the production of growth factors. Basic fibroblast growth factor (bFGF) has been implicated in the control of cell proliferation, differentiation, and embryonic development. To clarify its role in uterine remodeling, the cellular distribution of bFGF was examined immunohistochemically in the rat uterus during early pregnancy (Days 2-6). Basic FGF localized intracellularly in stromal and epithelial cells and within the extracellular matrix at Days 2 and 3. It was distinctly evident at the apical surface of epithelial cells at Days 4 and 5 of pregnancy. Concurrent with this apical localization, bFGF was present in the uterine luminal fluid, suggesting release of this growth factor from epithelial cells. Embryonic implantation was accompanied by increased intracellular bFGF content in luminal epithelial and decidual cells. However, similar cells outside of the implantation site and in the artificially decidualized uterus did not express analogous bFGF levels, indicating that a unique signal from the embryo triggers bFGF expression. Changes in the cell-specific distribution of bFGF imply a multifunctional role for this growth factor in uterine cell proliferation, differentiation, and embryonic implantation. In addition, the apical release of bFGF from epithelial cells indicates utilization of a novel secretory pathway for bFGF export during early pregnancy.
细胞增殖和分化是胚胎植入前子宫重塑的关键组成部分。最近的研究表明，卵巢激素雌激素和孕酮通过生长因子的产生来调节这些细胞事件。碱性成纤维细胞生长因子（bFGF）与细胞增殖、分化和胚胎发育的控制有关。为了阐明其在子宫重塑中的作用，在妊娠早期（第2 - 6天）通过免疫组织化学方法检测了大鼠子宫中bFGF的细胞分布。在第2天和第3天，碱性成纤维细胞生长因子定位于基质细胞、上皮细胞内以及细胞外基质中。在妊娠第4天和第5天，它在上皮细胞的顶端表面明显可见。与这种顶端定位同时出现的是，bFGF存在于子宫腔液中，表明这种生长因子是从上皮细胞释放出来的。胚胎植入伴随着腔上皮细胞和蜕膜细胞内bFGF含量的增加。然而，植入部位以外以及人工蜕膜化子宫中的类似细胞并未表达类似水平的bFGF，这表明来自胚胎的独特信号触发了bFGF的表达。bFGF细胞特异性分布的变化意味着这种生长因子在子宫细胞增殖、分化和胚胎植入中具有多功能作用。此外，bFGF从上皮细胞的顶端释放表明在妊娠早期利用了一种新的分泌途径来输出bFGF。
