Yeomans N D, Trier J S, Moxey P C, Markezin E T
Gastroenterology. 1976 Nov;71(5):770-7.
Gastric mucosa of fetal rats undergoes striking developmental changes during the last few days of gestation in utero. To investigate some aspects of this process, gastric explants from 18-day fetuses (4 days before birth) were maintained in organ culture for 3 days, then assessed by light and electron microscopy. The epithelia from base line uncultured stomachs were stratified and morphologically undifferentiated. During culture in basic medium (Leibovitz L 15), modest maturation of antral and fundic architecture occurred, characterized by epithelial invagination to produce small pit-glands. Secretory granules appeared in occasional epithelial cells, and cytochemistry indicated that most were mucous granules. Addition of pentagastrin (10(-9) to 2 X 10(-7) M) did not induce further morphological maturation in this system. However, addition of cortisol (10(-6) to 10(-5) M) resulted in a marked, dose-related increase of pit-gland formation and of cytological differentiation (appearance of secretory granules). This cortisol-induced architectural maturation was completely inhibited by the mold metabolite cytochalasin B (10(-5) M). The results indicate that fetal gastric maturation can be partially reproduced by culture in chemically defined media, and also suggest that corticosteroids may plan an important role in gastric organogenesis.
胎鼠的胃黏膜在子宫内妊娠的最后几天会发生显著的发育变化。为了研究这一过程的某些方面，将18日龄胎儿（出生前4天）的胃外植体在器官培养中维持3天，然后通过光学显微镜和电子显微镜进行评估。未培养的基线胃上皮为分层结构，形态上未分化。在基础培养基（Leibovitz L 15）中培养期间，胃窦和胃底结构出现适度成熟，其特征为上皮内陷形成小的隐窝腺。偶尔有上皮细胞出现分泌颗粒，细胞化学表明大多数是黏液颗粒。添加五肽胃泌素（10^(-9)至2×10^(-7) M）在该系统中未诱导进一步的形态成熟。然而，添加皮质醇（10^(-6)至10^(-5) M）导致隐窝腺形成和细胞学分化（分泌颗粒出现）显著增加，且与剂量相关。这种皮质醇诱导的结构成熟被霉菌代谢产物细胞松弛素B（10^(-5) M）完全抑制。结果表明，在化学成分明确的培养基中培养可以部分重现胎儿胃的成熟过程，也提示皮质类固醇可能在胃器官发生中起重要作用。
