Epithelial-interstitial cell interactions in fetal rat lung development accelerated by steroids.
Epithelial-interstitial cell interactions in fetal rat lung development accelerated by steroids.
复制标题
类固醇加速胎鼠肺发育中的上皮-间质细胞相互作用。
DOI：
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发表时间：
1986
期刊：
影响因子：
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通讯作者：
G. King
中科院分区：
文献类型：
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作者：
I. Adamson;G. King
细胞与细胞的直接接触被认为是成纤维细胞因子影响发育中的肺上皮细胞分化的手段。为了进一步证明这一假说，现在我们研究了当注射类固醇后肺发育加速时，上皮细胞-间充质细胞接触的作用。从妊娠第17天到第22天对雄性和雌性大鼠胚胎进行了研究。胎儿来自母亲，生前2天注射地塞米松2 mg/kg，生前1小时注射[~3H]胸腺嘧啶核苷。在快速生长期注射类固醇降低了胎儿肺中的总DNA，从放射自显影来看，这种影响在上皮细胞中最为明显。激素后分化较早，上皮细胞中板层小体较多，饱和磷脂酰胆碱水平较高。从定量的超微结构研究来看，这些磷脂的变化与上皮-间质细胞接触频率的增加有关。类固醇治疗并没有消除对照组中出现的与性别相关的差异；无论是男性还是女性，都表现出细胞间接触和肺部脂肪合成的增加。结果表明，随着表面活性物质合成的增加，上皮细胞成熟的加速与上皮-间质细胞接触的增加有关。这支持这样一个概念，即来自胎儿成纤维细胞的调节信息直接传递到特定的上皮细胞，以启动表面活性物质的合成。
Direct cell to cell contact has been suggested as the means whereby fibroblast factors influence epithelial cell differentiation in the developing lung. To obtain further evidence for this hypothesis, the role of epithelial-mesenchymal cell contacts is now examined when lung development is accelerated after steroid injection. Male and female rat fetuses were studied from day 17 to day 22 of gestation. The fetuses were from mothers injected with 2 mg/kg of dexamethasone at 2 days before death and [3H]thymidine at 1 hour before death. Steroid injected during the rapid growth phase reduced total DNA in fetal lung, and from autoradiographs, the effect was most noticeable in epithelial cells. Differentiation began sooner after steroid; more epithelial cells contained lamellar bodies and disaturated phosphatidylcholine levels were higher. From quantitative ultrastructural studies, these changes in phospholipid correlated with an increased frequency of epithelial-interstitial cell contacts. Steroid treatment did not abolish the sex-related difference seen in controls; both males and females showed increases in cell to cell contacts and in lipid synthesis in the lung. The results demonstrate that acceleration of epithelial cell maturation with increased surfactant synthesis is associated with increased epithelial-interstitial cell contacts. This supports the concept that regulatory messages from the fetal fibroblast are passed directly to specific epithelial cells to initiate surfactant synthesis.